Citrograph - Citrus Research Board

CitrographMAY/June 2013 • Volume 4 • Number 3Cover photo by Teresa FergusonSUBSCRIPTIONSU.S.Single Copies: $1.501-Year Subscription: $15.002-Year Subscription: $28.00Send Subscription Requests To:Citrus Research BoardP.O. Box 230, Visalia, CA 93279PUBLICATION OFFICEP.O. Box 230Visalia, CA 93279Phone: 559-738-0246Louise Fisher, Managing EditorDr. MaryLou Polek, Chief Science EditorEDITORIAL BOARDDr. Mary Lu ArpaiaTed BatkinRichard BennettFranco BernardiDan DreyerDr. Ben FaberJim GordenJulia InestrozaDennis LauxJudy BrentDale Hahn, DesignProduction Manager Phone: 630-462-2308255 38th Avenue Suite P dhahn@farmprogress.comSt. Charles, IL 60174Phone: 630-462-2919jbrent@farmprogress.comADVERTISING INFORMATIONSandy CreightonAd Sales ManagerPhone: (559) 201-9225screighton@farmprogress.comADVERTISING RATESCanadian & Foreign:1-Year Subscription: $30.002-Year Subscription: $56.00FAX: 559-738-0607Web Site:http://www.citrusresearch.orgSCIENCE REVIEW PANELDr. Mary Lu ArpaiaJames A. BethkeDr. Abhaya DandekarDr. Akif EskalenDr. Stephen GarnseyDr. Joseph SmilanickEditorial services provided by Anne Warring,Warring Enterprises, Visalia, CA 93277PRODUCTION INFORMATIONRates B/W 2/C 4/CPage..................................$690....... $860...... $10252/3 Page Vertical.................540......... 700.......... 8751/2 Page Vert/Horiz............410......... 580.......... 7501/3 Page Square/Vert..........285......... 455.......... 6201/4 Page..............................200 ........ 370.......... 5401/6 Page Vertical.................140......... 310.......... 4801/8 Page Horizontal............140......... 310.......... 480*Frequency discounts: 2X–5%, 3X–7%, 4X–10%Above rates are gross; 15% discount to recognized agencies.An Official Publication of the Citrus Research BoardIN THIS ISSUE4 Editorial6 Chairman’s View12 Maintenance of citrus microirrigationsystems22 How does nitrogen move in the soil?30 VRI: Thinking outside the rectangle36 Technical and financial assistancefrom NRCS38 Advanced Pumping Efficiency Program42 A ‘Thank You’ note to John Pehrson48 Understanding citrus branch cankerand dieback in the Southern Californiadesert regions52 New postharvest treatments forimproved management of green mold,sour rot, and brown rot of citrus60 Citrus Roots: The Building Boomof 1925-26 caused a relinquishment ofcitrus acreageCitrograph is published bimonthly by the Citrus Research Board, 217 N. Encina, Visalia, CA 93291. Citrograph is sent to allCalifornia citrus producers courtesy of the Citrus Research Board. If you are currently receiving multiple copies, or would liketo make a change in your Citrograph subscription, please contact the publication office (above, left).Every effort is made to ensure accuracy in articles published by Citrograph; however, the publishers assume no responsibilityfor losses sustained, allegedly resulting from following recommendations in this magazine. Consult your local authorities.The Citrus Research Board has not tested any of the products advertised in this publication, nor has it verified any of thestatements made in any of the advertisements. The Board does not warrant, expressly or implicitly, the fitness of any productadvertised or the suitability of any advice or statements contained herein.May/June 2013 Citrograph 3

EDITORIALBY TED A. BATKIN, Citrus Research Board president August 1993/May 2013The Final Word!!I do want to take thisopportunity to thankyou, the growers ofcitrus in California, forthe opportunity to servethis noble industry forthe past 20 years.Ihave always wanted to say that! However, this will be my finaleditorial as President of the Citrus Research Board. As of June1st, Ken Keck has taken the helm of the CRB. Please note thewonderful cover photo by Teresa Ferguson from the CRB staff.The program will be in great hands with Ken, as he brings a wealth ofexperience to the Board and to the program. You read about his backgroundin the March/April Citrograph and will, of course, learn muchmore about him in upcoming issues.I do want to take this opportunity to thank you, the growers ofcitrus in California, for the opportunity to serve this noble industryfor the past 20 years. When I first took the leadership, we had a staffof one (me) and have grown to a program with multiple elements and15 full-time staff members in three locations throughout the state. Weoperated with a staff of four for the first 15 years. In 2008, with theintroduction of the Asian citrus psyllid (ACP), we expanded to over40 personnel with the statewide trapping and detection program. Lastyear we transferred many of those duties to CDFA for regulatory purposes,leaving the current staff levels.The ACP and huanglongbing issues are still with us and will befor many years to come. This devastating HLB disease will haunt thegrowers from now on until a permanent solution can be found throughscientific development. I fully believe that there will be a cure for HLBthat will keep the California industry alive and vital for centuries tocome. The scientific community is close to unlocking the critical factorsto bring resistant rootstocks and early detection diagnostictechnologies to provide you, the growers, the tools necessary to survivethe disease.There will be more challenges to the industry from invasivepests and diseases -- some of which we already know and othersthat have not even been discovered yet. This is just the evolutionarycycle of things in agriculture. I also believe that the industrywill continue to build on the knowledge base currently availableto meet these challenges and survive the threats as they comeforward.There is not enough room in this entire magazine to thank all ofthe wonderful folks who have made my career the true joy that it hasbeen. Everyone that I have been associated with has added to my lifeand brought something of value to me and to the program. To all ofyou, a very heartfelt THANK YOU!! l4 Citrograph May/June 2013

The Yara CompleteCitrus Crop ProgramEarlyVegetativeGrowth/FlushFloweringFruitsetFruitfillPostharvestYaraMila ®15 - 15 - 1520% oftotal N /10% oftotal K2O30% oftotal N /15% oftotal K2OYaraLiva ®CN-9 ® / Tropicote ®20% oftotal N30% oftotal N13 - 0 - 4620% oftotal K 2O30% oftotal K 2O25% oftotal K 2OYaraVita ®Correction of nutrient deficiencies based on tissue analysisFor more information, please contact:Ron Naven, Northern California: 916 632 3120Jon Collison, South Central Coast: 661 589 8796Leonard Hammer, Central California: 559 834 4616Andy Hancock, Southern California: 928 345 2276Scan for crop advice &support documents

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IRRIGATIONMaintenance of citrus microirrigation systemsLarry Schwankl and Ben FaberIntroductionMicroirrigation systems (drip andmicrosprinklers) used in citrus allowthe manager to irrigate efficiently, applyingjust the right amount of water atthe desired time. The systems are costly,so it is important that they operateas designed to deliver their maximumperformance.This requires that the microirrigationsystem be maintained properly,with particular care given to make surethat the drippers or microsprinklersare not clogged.A clogged microsprinkler or dripemitter results in the trees receivingless water than planned, and deficit irrigationof the trees can hurt yield andquality.Drippers or microsprinklers thatare totally clogged are more easilyspotted, but partial clogging is oftennot easily detected, especially with dripemitters. Even totally clogged drippersor microsprinklers will not be foundif the microirrigation system is not inspectedregularly. Therefore, frequentsystem inspections (during each irrigation)are the first important step tomaintaining a drip or microsprinklersystem.Leaks -- also a problem with microirrigationsystems -- can be checkedfor during the routine system inspections.Leaks, which can be caused byanimal or human damage to the systemor simply by a fitting coming loose, areoften easily detected by sight or sound.The emitters can be clogged dueto a variety of reasons, and sometimesmultiple issues may be involved. Forthis article, it is useful to break thesources of clogging into categoriesto discuss their causes and solutions.Clogging caused by suspended material,by organic materials, and by chemicalprecipitates will be discussed.Clogging caused by suspendedmaterialsSuspended materials in irrigationwater may be inorganic (sand, silt, andclay), organic (algae, bacteria, plantdebris, fish, insects, insect larva, and12 Citrograph May/June 2013

acterial slimes), or any other floatingor suspended matter. These materialsmust be removed from irrigation waterby filtering prior to use in microirrigationsystems to prevent emitter clogging.Filtration equipment for removingsuspended materials includes:• centrifugal sand separators• sand media filters• pressurized screen filters• suction screen filters (installed onthe intake of centrifugal pumps)• gravity flow screen filters• disc filtersCentrifugal sand separators removelarger particles of sand. Waterentering the separator rotates aroundit, developing centrifugal forces thatcause the sand particles to move to theouter edge of the separator. These particlesthen settle out of the water intoa collection chamber at the bottom ofthe unit. Clean water flows out of theseparator at the vortex of the rotation.Gravity flow screen filters operateby having water flow by gravity througha screen with the contaminants beingcaptured on the screen while the cleanwater drops through the screen whereit is collected and pressurized for use inthe microirrigation system.Pressurized screen filters operateunder the same pressure as the restof the microirrigation system. As wateris forced through the screen filter,the contaminants are caught on thescreen. Periodically, the screen mustbe cleaned, either manually or somescreen filters have automatic backwashsystems.Disk filters consist of a stack ofdiscs, each containing a series of verysmall grooves. As water flows throughthe grooves, the contaminants arecaught and removed. The clean waterpasses into the microirrigation system.The degree of filtration for screenand disk filters is expressed as meshsize or equivalent mesh size. The meshsize is the number of openings per inch.For example, a 200-mesh filter has 200openings per inch in the filter. Theemission device manufacturer oftenprovides the required degree of filtration,so they should be contacted forinformation.The degree of filtration for sandmedia filters is determined by the particlesize of the sand used. The tablebelow shows the correspondence betweensand size and mesh sizes. It ismost common to find number 16 ornumber 20 sand used in sand mediafilters.Sand No. Equivalent Mesh Size8 7011 14016 17020 23030 400Screen filters, disc filters, and sandmedia filters can all be designed toremove the same size particle, so thebest filter to use depends on the typeof material suspended in the irrigationwater. Generally, sand media filters areused to remove algae and other organicmaterial; they are effective in removingthese materials without the need forfrequent backflushing. Screen and discfilters can remove organic material, butthey can clog rapidly and require frequentbackflushing.Clogging caused by organic materialsBiological growths in drip lines andemitters can be a serious problem whenthe irrigation water contains organicsediments, dissolved iron, or hydrogensulfide. The primary biological growthsin drip systems are algae and bacteria.Algae occur in surface waters usedfor irrigation; their food sources includecarbon dioxide, nitrogen and phosphorus.While the filtration of microirrigationsystems removes some of thealgae, small particles of algae can passthrough the filter into the drip system.Algae also provide an organic carbonfood source for slime organisms.Bacteria discolor the water andform precipitates and slimes that stickto the walls of the emitter flow passages.Bacterial clogging occurs when mineralfood sources are available in thewater along with suspended particlesto which the bacteria can attach. Foodsources include organic carbon (deadalgae), carbonates and bicarbonates,iron, and hydrogen sulfide.Iron rich water leads to the formationof iron bacteria, which convert solubleiron to insoluble iron precipitates.The result is a reddish slime in the driplines and emitters. The source of theiron bacteria is not clear but may bethe result of well contamination duringconstruction. Iron concentrations of 0.2ppm are sufficient for bacterial growth.Hydrogen sulfide in the irrigation wa-Typical reddish staining on building resulting from waterhigh in iron striking the building during irrigation.Sand media filters.May/June 2013 Citrograph 13

ter results in sulfur bacteria, a whitishslime with a rotten egg odor.Preventing biological growthsChlorine is often added to irrigationwater to oxidize and kill biologicalmicroorganisms such as algae, fungi,and bacteria that can cause emitterclogging. While these microorganismsmay be present in water from anysource, they are most likely to existat high levels in surface irrigation waterfrom rivers, canals, reservoirs, andponds.A common solution to this problemis either continuous injection tomaintain a residual chlorine concentrationof 1 to 2 ppm, or periodic injec-tions of 2 hours or more with chlorineconcentrations of 10 to 20 ppm. Thefrequency of the periodic injectionsdepends on the severity of the biologicalgrowths. Flushing of lateral lines isrecommended after a periodic chlorineinjection.High levels of microorganisms inwater introduced into a microirrigationsystem may clog the emitters. Usinga good filter (such as a sand mediafilter) and acidifying the water can cutdown on organic clogging, but someorganic material may still pass throughthe filter into the drip lines. Thus, chlorinationor some other biocide usuallyis needed to prevent clogging from organicmaterial.While chlorine is the most commonbiocide used in microirrigation systems,there are other products, such as copper-basedchemicals, which are also effectivebiocides.Desired chlorine concentrations• Continuous injection of chlorineshould be used if the irrigation waterhas high levels of algae and bacteria.The recommended level of free chlorineis 1 to 2 ppm at the end of theirrigation system. It is important tocheck the concentration at the end ofthe lateral line since chlorine is usedto oxidize the organic materials andreacts with any iron and manganese inthe water. The chlorine concentrationcan be determined with a good qualityswimming pool or spa chlorine test kit.• Periodic (e.g. once per month)injections at a higher chlorine concentrationrate (10 to 20 ppm) for 2 hoursor more may be appropriate wherealgae and bacterial slimes are less ofa problem. The frequency of injectiondepends on the potential organic clogging.Injection method Chlorine concentrationat the end of thelast lateralContinuous injection 1 – 2 ppmPeriodic injection 10 – 20 ppmA diaphragm pump injector in the foreground, and in the background a bypassventuri injector with an electric booster pump.Venturi injector with an electric booster pump bypass system.Forms of chlorineCommon sources of chlorine arechlorine gas, sodium hypochlorite(household liquid bleach), and calciumhypochlorite (powder or granules).Adding chlorine to water producesmainly hypochlorous acid and hypochlorite,both referred to collectively asfree available chlorine. Hypochlorousacid is the most effective agent for controllingbiological growths. Its concentrationdepends on the pH of the water.When a pH of 7 or less is maintained,at least 75% of the chlorine in the wateris hypochlorous acid, while at a pHof 8 only about 25% of the chlorine ishypochlorous acid. At a pH of less than3, chlorine gas predominates.Chlorine gas: Dissolving chlorinegas in water produces hypochlorousacid, hydrogen, and chloride. Chlorinegas contains 100% available chlorinebecause it lowers the pH of the waterto a level that results in mostly chlorineand hypochlorous acid. While usingchlorine gas is generally considered14 Citrograph May/June 2013

the least expensive method of injectingchlorine, it is the most hazardous andrequires extensive safety precautions.Trained personnel are needed for installingand using chlorine gas injectionsystems.The chlorine gas injection rate canbe calculated from the following equation:IR = Q x C x 0.012where:IR = the injection rate in poundsper day (the most common unit usedfor chlorine gas injection systems).Q = the irrigation system flow ratein gallons per minute (gpm).C = the desired chlorine concentrationin the water in parts per million(ppm).Sodium hypochlorite: Sodiumhypochlorite ([commercial?] liquidbleach) is usually available with up to15% available chlorine. Householdbleach is sodium hypochlorite with5.25% available chlorine. Most liquidfertilizer injection equipment is capableof injecting liquid chlorine. If theinjection point is downstream of the filters,it may be necessary to hand treatthe filters with chlorine.Adding sodium hypochlorite towater produces hydroxyl ions, whichraises the pH of the water and, in doingso, may decrease the effectivenessof chlorination. If the water pH risesabove 7.5, acid injection may be neces-sary to reduce the pH and increase thechlorine’s effectiveness.Do not mix chlorine (e.g. commercialor household liquid bleach) andacids together because that can causethe formation of chlorine gas, whichis highly toxic. Use different storagetanks and injection ports for acid andchlorine.Use the following equation to determinethe chlorine injection ratewhen using sodium hypochlorite:IR = (0.006 x Q x C) ÷ Swhere:IR = the injection rate in gallonsper hour (gph).Q = the irrigation system flow ratein gallons per minute (gpm).C = the desired chlorine concentrationin the water in parts per million(ppm).S = the strength of the sodium hypochloritesource expressed as a percentage.Example: Sufficient householdbleach (5.25% chlorine) is to be injectedinto a drip irrigation system with aflow rate of 500 gpm so that the finalchlorine concentration in the irrigationwater is 5 ppm. What should the bleachinjection rate be?IR = (0.006 x 500 x 5) ÷ 5.25 = 2.9 gphCalcium hypochlorite: Calciumhypochlorite normally contains 65 to70% available chlorine. Note that 12.8pounds of calcium hypochlorite dissolvedin 100 gallons of water forms a1% chlorine solution. A 2% chlorinesolution therefore requires adding 25.6pounds of calcium hypochlorite to 100gallons of water.Any chlorine stock solution can bemixed following the same pattern. Theequation used for sodium hypochloriteinjection rates can be used for the calciumhypochlorite solution once thepercent concentration stock solutionis determined. Use caution when dissolvingcalcium hypochlorite in waterbecause of the possible formation ofchlorine gas.Clogging caused by calciumcarbonate precipitationPrecipitation of calcium carbonate(lime) is a common clogging problemin microirrigation systems. Water witha pH of 7.5 or higher and a bicarbonatelevel of 2 meq/l (120 ppm) is susceptibleto calcium carbonate precipitationif comparable levels of calcium arepresent naturally in the system or if amaterial containing calcium is injectedinto the system.Causes of calcium carbonateprecipitationThe occurrence of calcium carbonatein water at atmospheric pressuredepends on the pH and temperature ofthe water. At a pH less than 6, mostlyDisc filter.Irrigation reservoir with organic contaminants that shouldbe mitigated for prior to use with a microirrigation system.May/June 2013 Citrograph 15

IRRIGATIONOverview of soil moisture sensorsLarry Schwankl and Ben FaberSoil moisture sensors fall into twobroad categories: volumetric andtensiometric methods. One tellsyou how much water is in the soil, andthe other tells you how tightly the soilholds on to the water. Volumetric methodsrequire a calibration of the sensor tothe soil, whereas tensiometric is goodto-gowhen installed.For both methods, the growerlearns to keep soil moisture within agiven range of values, and, in theory, theplant is kept in a better condition withimproved health and yields and potentialimproved irrigation efficiency.The most common volumetricmethods rely on utilizing the dielectricconstants of the soil and water, withwater’s dielectric constant being muchgreater than soils’. The velocity of anelectromagnetic wave or pulse dependson soil moisture content.These sensors have become widelyused because they have a good responsetime, do not require maintenance,and can provide continuousreadings, allowing for automation.There are several different methodologiesused: Time Domain Reflectometry(TDR), Frequency DomainReflectometry (FDR) (Capacitance),Amplitude Domain Reflectometry(ADR) (Impedance), Phase Transmission(PT), and Time Domain Transmission(TDT).Soil moisture sensorsfall into two broadcategories: volumetricand tensiometricmethods. One tells youhow much water is in thesoil, and the other tellsyou how tightly the soilholds on to the water.Volumetric SensorsTDR FDR ADR PT TDTAppx. Cost $400-20,000 $100-3,500 $500-700 $200-400 $400-1,300(includinglogger/reader)+Field Maintenance No no No No NoAffected by salts High levels Minimal No >3dS/m High levelsSoil type not Organic, salt, None None None Organic,recommended high cay salt high clay+ Prices as of 2009Tensiometric SensorsTensiometer GB GMS HD SPAppx. Cost $50-300 $400-700 $200-500 $300-500 $500-1000(includinglogger/reader)+Field Maintenance Yes no No No NoAffected by Salts No >6 dS/m >6dS/m No maybeSoil Type not Sandy Sandy, high Sandy, high Sandy Sandy, highrecommended clay clay clayThere is quite a range in: (1) pricesfor these different devices, (2) requirementsfor calibration with soil moisturecontent, and (3) requirements for closesoil contact. Some devices are affectedby the chemical nature of the soil. Evenif they are not calibrated, they can beused as relative change in moisturecontent over time.The tensiometric methods include:Tensiometers, Gypsum Blocks (GB),Granular Matrix Sensors (GMS), HeatDissipation (HD), and Soil Psychrometer(SP). These techniques require thesensor to come into equilibration withthe soil moisture and generally are unaffectedby soil salinity. Gypsum blocksand Granular Matrix are not very responsivein sandy soils and requiregood soil contact. These methods areless affected by salinity and do not requiresoil calibration because they arereflecting the soil moisture tension theroots are seeing.All soil moisture sensors need to beplaced in a position that represents theirrigated area. They need to be placedin the active root zone where water isapplied and taken up and must be neartrees representative of the whole irrigatedarea. They should not be next toa sick tree, a smaller tree compared tothe other trees, or be in an area that obstructsapplied water (such as under acanopy that intercepts applied water).It is always best to reinforce sensorvalues with manual field measurementswith a soil probe to ensure that sensorplacement and response is truly reflectiveof what is going on in the field, beforecompletely relying on the sensorvalues.As with all field equipment, occasionalvisual inspection of the fieldand sensor readings should be madeto make sure the situation has notchanged, such as an emitter has cloggedor broken near the sensor.These sensors can be purchased individuallyand installed by the grower,or increasingly there are companiesthat provide a monitoring station thatincludes soil moisture sensors for estimatingplant evapotranspiration , datalogger and software that determines anirrigation schedule for the crop. Systemsare available by either an outrightpurchase or through a lease agreement.In the future, there will be affordablesatellite imagery that can help inirrigation scheduling, showing how rapidlythis technology is changing.l20 Citrograph May/June 2013

IRRIGATIONHow does nitrogen move in the soil, and whatare the factors that influence its movement?Jan W. Hopmans andMaziar M. KandelousEditor’s Note: An introduction to thissubject was presented by Dr. Hopmansat the Citrus Research Board’s2012 California Citrus Conference.The quality of groundwater isspecifically vulnerable in climaticregions where agricultural productionis possible only by irrigationsuch as in California and in many other(semi-) arid regions of the world.The regular application of nitrogenfertilizers with irrigation water islikely responsible for the increase innitrate concentrations of groundwaterresources such as in California’s mainagricultural areas in the Salinas Valleyand the Tulare Lake Basin. Therefore,improved irrigation water and soilmanagement practices are needed thattactically allocate water and dissolvedfertilizers to maximize their applicationuse efficiency, by minimizing fertilizerlosses through leaching towardsthe groundwater.Currently, the grower’s incentiveTo optimize fertigationpractices, it is essential thatirrigation is applied andfertilizers injected at theoptimal concentration, place,and time to ensure thatdeposition patterns coincidewith maximal root uptake.22 Citrograph May/June 2013for adopting improved fertigationpractices may be limited since fertilizercosts are only a small fraction ofthe total production costs, and changesin proposed fertigation practices maynot affect crop yield. However, groundwatercontamination regulations aregoing to be implemented; improvedfertigation practices may becomean essential part of California farmingoperations. We note that fertilizermanufacturing consumes about 3-5%of the world’s annual gas production.Moreover, increased nitrogen use efficienciesare key towards minimizingenvironmental and health impacts ofagricultural practices.Microirrigation has the potentialof precisely applying water and plantnutrients both in amount and in locationthroughout a field. Microirrigationsystems can be designed and operatedso that water and nutrients are appliedat a rate, duration, and frequency so asto maximize crop water and nutrientuptake while minimizing leaching ofnutrients and chemicals from the rootzone of agricultural fields.As stated by Bruulsema et al.(2008), optimal fertigation practice canonly be realized if knowledge of the 4R’s (right source, right rate, right place,and right time) are developed. To optimizefertigation practices it is essentialthat irrigation is applied and fertilizersinjected at the optimal concentration,place, and time to ensure that depositionpatterns coincide with maximalroot uptake.In addition to water and nutrients,sound and sustainable irrigation systemsmust maintain a long-term saltbalance that minimizes both salinityimpacts on crop production and saltleaching to the groundwater.The application of irrigation waterand fertigated nutrients, as well asroot growth, nutrient and water uptake,however, all clearly interact withsoil properties and fertilizer source ina complex manner that cannot easilybe resolved with “experience” or fieldexperimentation alone.While high field-wide uniformitiesare possible under microirrigation, thedistribution of both water and nitrateabout the drip line is very non-uniform.Both soil moisture content and nutrientconcentration will be the highestnear the drip line after applicationbut will redistribute thereafter as controlledby soil layering and other soilphysical properties.Because of these types of non-uniformwetting patterns, it is possible thatpercolation below the root zone andnitrate leaching occurs, despite that appliedirrigation water is equal or lessthan crop evapotranspiration (ET).The shape of the wetted soil volumeunder microirrigation and thespatial distribution of soil water andnitrate concentrations are dependenton many factors, including soil layering,soil hydraulic properties (waterretention and hydraulic conductivity),emitter discharge rates, spacing, andtheir placement (above or below thesoil surface), irrigation quantity andfrequency, crop water uptake rates, androot distribution patterns.In addition to the effect of soiltype, irrigation water and nutrient application,efficiency is determined bycrop-specific root development. Waterand nutrients should not be applied inareas where roots are absent, or at arate higher than the roots can possiblytake up.In general, root development isconstrained to the soil volume wettedby the emitters, with root length densitydecreasing with depth, whereasplants can quickly adapt their spatialpattern of water and nutrient uptake inresponse to irrigation water applicationdistribution. Also, roots can adjust theiruptake patterns, thereby compensatingfor local stress conditions by enhancedor preferential uptake in other regionsof the rooting zone with less stressfulconditions.

A better understanding of the interactionsof irrigation method, soiltype, crop root distribution, and uptakepatterns and rates of water and nutrientsor solutes will provide improvedmeans for proper and efficient microirrigationwater management practices.A comprehensive review of thefunctional role of plant root water andnutrient uptake was presented by Hopmansand Bristow (2002). We note thatelemental nitrogen becomes availablefor the plant in different forms and istypically applied by synthetic fertilizerand/or manure applications. Otherforms of nitrogen come from soil organicmatter and through nitrogen fixatinglegumes.In most applications, the nitrogenis originally bound in organic form andmust be mineralized to become availablefor plants in soil solution. Whena synthetic fertilizer is applied in theform of urea, it must be hydrolyzed byan enzymatic reaction. Natural organicforms such as soil organic matter andanimal wastes are broken down by soilmicrobes to nonorganic forms.Either way, whether by hydrolysisor mineralization, it becomes availableas ammonium (NH 4+), which will furtherbe nitrified microbially to nitrate(NO 3-). Both of these nitrogen formsare available to the plant; however, ammoniumquickly nitrifies to nitrate sothat most of the soil nitrogen is takenup in the nitrate form.In addition to the water-solubleform, nitrogen may transform in thegaseous form, into ammonia gas, or byway of denitrification of water-solublenitrate into nitrous oxide. The amountof ammonia volatilization depends onsoil environmental conditions but isespecially high for dry conditions andhigh temperatures, so that it is minimizedwhen urea is applied duringwetter and cooler soil conditions. Denitrificationof water-soluble nitrate intonitrous oxide by anaerobic bacteria canbe particularly relevant in water-saturatedconditions, when oxygen concentrationsare low and soil temperaturesare relatively high.How does irrigation water movethrough the soil?In answering the question of hownitrogen moves through the soil, wemust first and foremost acknowledgethat much of its movement will occurFig. 1. Tensiometer types for soil suction measurements using vacuum gaugesand electronic pressure transducers, as illustrated in Or, Tuller and Wraith (2004).Key TermsDenitrification: Loss of soil nitrogen by reduction of soil nitrates to gaseousnitrogen by microorganisms in a series of biochemical reactions, includingto nitric oxide (NO), nitrous oxide (N 2O) and nitrogen gas (N 2). Occursespecially in anaerobic and wet soil conditions.Perching: Development of water logging conditions in soils, as caused bylow permeability soil layers that prevent soil water drainage.Evapotranspiration: Soil water depletion by combination of soil and plantleaf evaporation. The latter is called plant transpiration and occurs by rootwater uptake and subsequent water evaporation through small openings(stomata) in plant leaf surfaces.Hydraulic conductivity: Soils ability to transmit water. Its magnitude varieswith soil water content and soil type, as it is controlled by connectivityof the water-filled soil pores.Diffusion: Mixing of water dissolved nutrients in soil solution, as a resultof thermal motion of molecules. It magnitude is proportional to differencesin concentration, and moves nutrients from regions of higher to lower concentration.Dispersion: Tendency towards mixing of water dissolved nutrients in soilsolution, as a result of soil water movement (advection), as caused by watervelocity variations in the water-filled soil pores.Cbar: Unit of soil water suction (pressure), with 1.0 cbar equal to one hundredthof a bar or 1.0 kPa.Macropores: Soil pores that contribute to soil structure (as opposed tosoil texture). These are the larger pores as created by plant roots, soil fauna,or by soil shrinking, and are the pathways for rapid water movement,likely leading to leaching of water and nutrients below the rooting zone,especially at or near soil saturated conditions.Soil adsorption: Capability of soil particles to adsorb chemicals, includingnutrients. Magnitude is typically controlled by the soil’s cation exchangecapacity and specific electrical charge of chemical adsorbed.Vadose zone: The region between the ground surface and the groundwater(“vadose” is from the Latin for “shallow”). Often is also referred to as theunsaturated zone.May/June 2013 Citrograph 23

Fig. 2. Soil water retention and hydraulic conductivity curves for different soiltypes. Shaded portions represent the variation in hydraulic values as a result ofvariations in measured soil water suction values across the field.in a water-soluble form. Therefore, inirrigated agricultural systems, nitrogentransport in soils is largely controlledby its movement with the irrigation water.So, to better understand the fate ofnitrogen in irrigated fields, we must acceptcertain soil physical principles thatcontrol soil water movement.The two main soil properties thatdefine water flow are the soil waterretention and hydraulic conductivitycurves, both of which are very soil-specificand largely depend on soil textureand structure, and specifically on soilpore size and pore connectivity.The soil-water retention functiondetermines the relation betweenthe soil’s suction forces and soil watercontent, u, and is also known as thesoil-water release or soil-water characteristiccurve. The soil water suction(S) is caused by the soil’s capillary andadsorptive forces. These suction forcesincrease as the size of the water-filledFig. 3. Spatial distribution of soil solution urea, ammonium, and nitrate concentration of DRIP irrigation for various daysduring the simulation period. The times (days) correspond to the end of the first irrigation/fertigation (1.5), beginning ofthe second irrigation (3.5), beginning of second fertigation (3.54), end of second fertigation (3.63), end of second irrigation(5.0), beginning of third irrigation (7.0), end of last irrigation/fertigation (26.0), and end of simulation period (28.0).24 Citrograph May/June 2013

distribute thereafter as controlled bysoil physical properties. Because of thetypical non-uniform wetting patterns,it is essential to use multi-dimensionalmodeling to develop optimal fertigationpractices for maximum nutrientuse efficiency. The contour plots showthe simulated concentrations of N-speciesin the soil water.The first panel shows a band ofurea along the periphery of the wettedsoil volume with little or no urea nearthe drip line, except immediately afterfertigation (t=3.63 days). There was relativelylittle change during subsequentirrigation cycles, indicating that littleurea accumulation occurred in the soilprofile. However, urea concentrationsdecreased with time between irrigationsas a result of hydrolysis.As expected, at 3.63 days, the ureawas concentrated near the drip line,immediately after fertigation. Someslight preferential lateral movementoccurred, likely because of occasionalsoil surface ponding.As expected, ammonium remainedconcentrated in the immediate vicinityof the drip line at all times, becauseof soil adsorption and subsequent fastnitrification and/or root uptake. Incontrast to ammonium, nitrate movedcontinuously downwards during the28-day simulation period, as nitrate isnot adsorbed.As expected, high nitrate concentrationsoccurred near the drip lineimmediately after fertigation, but littlenitrate remained near the drip line atthe end of the irrigation (t = 5.0 days),because of root uptake and downwardtransport. At this time, most of the nitratewas distributed near the peripheryof the wetted region due to leachingfollowing the fertigation. However,by the start of the next irrigation (t =7.0 days), nitrate levels near the dripline increased, the result of nitrificationof ammonium. Between irrigations, nitrateconcentrations near the drip linedecreased due to redistribution androot water uptake.In general, except for times immediatelyafter fertigation, nitrate concentrationswere relatively low, with thehighest values along the wetting front.Bands of nitrate reflect the wetting patternsafter each irrigation cycle. At theend of the last irrigation event of thesimulation period, nitrate was distributedthroughout the wetted soil profileto a soil depth of about 150 cm, indicatingpotential leaching after 28 days.General discussionWhereas simulation models suchas HYDRUS-2D are enormously usefulto evaluate different irrigationmanagement practices, much of whatis lacking is continuous field experimentaldata of soil water content, suctionand soil nitrate concentration, allowingadequate model testing.Moreover, to date our work hasclearly demonstrated the large importanceof soil type and soil layering onwater and nutrient leaching, and muchbetter soil characterization is requiredespecially for the typical highly variablesoils in alluvial settings such as inthe San Joaquin Valley.Whereas current experimental effortsare largely limited to monitoringof the soil zone, and quantification ofUniquely effective productsfor controlling major pests incitrus with minimal disruptionto IPM programs.Citricola ScaleCottony Cushion ScaleCalifornia Red ScaleCitrus Red MiteTwo-spotted Spider MiteBud MiteContact Your area Nichino America salesrepresentative to learn more.©2012. Nichino America, Inc. All rights reserved. APPLAUD ® and FujiMite ® aretrademarks of Nichino America, Inc. Farm Safely. Always read and follow labeldirections. 888-740-7700 www.nichino.netMay/June 2013 Citrograph 27

leaching potential out of the rootingzone, additional efforts are required toquantify flow and movement of nitratesto the groundwater.Relatively few experimental studieshave studied the deeper soils andvadose zone and the importance ofdeep subsurface formations on perching,nitrate transport to the groundwater,and denitrification. An exception isa 52-feet deep experimental study byHarter et al. (2005) in Fresno County,demonstrating that the alluvial sedimentarygeology is highly heterogeneous,and must be considered wheninterpreting deeper transport of nitratesto the groundwater.Though, in general, basic conceptsof soil nitrate transport are well understood,many challenges remain. Wetentatively conclude that (a) nitrateleaching rates are largely controlled byirrigation type and soil heterogeneity(texture, layering), and (b) soil watersuction measurements such as by tensiometersare critical towards quantifyingnitrate leaching rate towards thegroundwater.Much more research is requiredto assess travel times of soil solutionnitrate and to relate soil solution withgroundwater nitrate concentration.Improved subsurface monitoring technologiesmust be developed to allowfor accurate real-time nitrate leachingrates, especially as related to nitrate solutionconcentration and flow rates.Furthermore, crop nitrate demandat specific phenomenal stages are neededso that fertigation timing can be optimized,dosing the applied nitrate withthat needed for maximum crop production.Additional fundamental plantroot studies would have to be designedto understand root water and nutrientuptake by plant roots, as controlled bychanging soil conditions such as waterand salinity stresses and root zone nutrientconcentration. Whereas leachingis among the major potential losses offield-applied nitrate, denitrification ofnitrate into gaseous forms of N 2O andN 2is another major way that may reducenitrate use efficiency. Therefore,much more experimental work is neededto help mitigate those losses.Though, in general,basic concepts of soilnitrate transport arewell understood, manychallenges remain.Jan W. Hopmans is Professor ofVadose Zone Hydrology and MaziarKandelous is a graduate student in theDepartment of Land, Air and WaterResources at UC Davis. Dr. Hopmansserves as Associate Dean of the Collegeof Agricultural and EnvironmentalSciences at UC Davis and is the president-electof the Soil Science Societyof America.The authors note that some of thediscussion in this article was made possiblethrough a research grant by theAlmond Board of California.ReferencesBruulsema T.W., C.W., FernandoGarcía, Shutian Li, T. Nagendra Rao,Fang Chen, and S. Ivanova (2008). “AGlobal Framework for Fertilizer BMPsBetter Crops with Plant Food. IN BetterCrops with Plant Food, Vol. 92(2):13-15.Dawson, C.J., and Jilton, J. 2011.Fertilizer availability in a resource-limitedworld: Production and recycling ofnitrogen an phosphorus. Food Policy.Doi:10.1016/j.foodpol.2010.11.012.Hanson, B.R., J. Simunek, and J.W.Hopmans. 2006. Evaluation of Urea-Ammonium-Nitrate Fertigation withdrip irrigation using numerical modeling.Agricultural Water Management86:102-113.Harter, T., Y. Onsoy, K. Heeren, M.Denton, G. Weissman, J.W. Hopmans,and W.R. Horwath. 2005. Deep vadosezone hydrology demonstrates fate ofnitrate in the eastern San Joaquin Valley.California Agriculture. 59(2):124-132.Harter, T. and J.R. Lund, 2012. AddressingNitrate in California’s DrinkingWater. With a Focus on Tulare LakeBasin and Salinas Valley Groundwater.Center for Watershed Sciences, Universityof California, Davis.Hopmans, J.W., and K.L. Bristow.2002 Current capabilities and futureneeds of root water and nutrient uptakemodeling. Advances in Agronomy.Volume 77: 104-175, 2002.Or. D., M. Tuller, and J. M. Wraith.2004. Water potential. In D. Hillel (Ed.),Encyclopedia of Soils in the Environment- Volume 4, Elsevier Ltd., Oxford,U.K., pp.270-277.Šimůnek, J., van Genuchten, M.Th. and Šejna, M. 2008. Developmentand applications of the HYDRUS andSTANMOD software packages, and relatedcodes, Vadose Zone Journal, 7(2),587-600. lSuccessful growers likeMark Campbell of Willits &Newcomb cover their Citruswith Agra Tech Greenhouses.Agra Tech is here to helpyour crop stay healthy andprotected from Psyllids. 28 Citrograph May/June 2013

ThripsLeafminerKatydidsPeelminerAsian citrus psyllidDelegate ® Insecticide.By blasting out of spray rigs andhammering destructive pests, Delegate helps protect your citrus groves. Andwhile the innovative mode of action of Delegate is broad-spectrum enough tocontrol multiple pests, it maintains populations of most beneficials. Mites aren’tflared, and secondary pests stay…secondary. You also get favorable pre-harvestand re-entry intervals, plus minimal personal protective equipment requirements.To learn more, talk to your PCA or visit www.dowagro.com.®Trademark of Dow AgroSciences LLCAlways read and follow label directions.

TREES NOTPERFORMING LIKETHEY SHOULD?Small Size?Low Yield?Poor Packouts?• Proprietary Foliar Sprays• Custom Blended Fertilizer• All Lines of Crop Protection• Organic Products• PhD Citrus Agronomist on StaffLEFFINGWELLSALES CO.INC.INC.CO.SALES AGProviding QualityService to GrowersSince 1920Ivanhoe - Lindsay - Terra Bella559.562.4946www.leffingwellag.commonitored for both efficiency and regulatory purposes.Terrain complicates nutrient management for citrusgrown in the foothills. “Keeping track of nutrients in westernsoil is more difficult than in the flatlands because much ofthe soil is water-formed and hilly, which means it has variabilityboth laterally and vertically,” says Bassett. “Depth ofsoil horizon is a major factor for western growers in nutrientmanagement.”Additionally, VRI maintains the proper moisture environmentfor nutrients to be retained in the soil, rather thanleaching out of the root zone and into water supplies. This isimportant in crops with deep roots that may span multiplesoil horizons, like citrus.Whatever the benefits of improved irrigation may be toa citrus grower, VRI puts the reins in the grower’s hands.“In my opinion, the biggest benefit is control. Control of theroot zone, by soil type,” says Bennett. “Water conservationis important also, but the control that VRI gives a growerover the nutrients and activity going on in the root zone isinvaluable.”Randi Gwilliam writes on behalf of the Tulare-basedTAP Family of Companies, focusing on agronomic principlesand practices in California.ReferencesLaRue, J., and R. Evans. 2012. Considerations for VariableRate Irrigation. Proceedings of the 24th Annual CentralPlains Irrigation Conference, February 21-22, 2012, Colby,Kansas. (Kansas State University, 2012.)O’Green, A.T., Pettygrove, S., Southard, R.J., Minoshima,H. and Verdegaal, P.S., 2008. Soil-landscape model helpspredict potassium supply in vineyards, California Agriculture62(4):195-201. DOI: 10.3733/ca.v062n04p195.October-December 2008. (UCANR, 2008)Perry, C., and S. Pocknee. 2003. Development of a Variable-RatePivot Irrigation Control System. Proceedings ofthe 2003 Georgia Water Resources Conference, held April23-24, 2003, at the University of Georgia. (University ofGeorgia, 2003.)Perry, C.D. and Milton, A.W. 2007. Variable-rate irrigation:concept to commercialization. Proceedings of the 29thSouthern Conservation Agricultural Systems Conference,25–27 June, 2007, Quincy, Florida. (University of Georgia,2007.)Vories, E.D. 2008. Variable Rate Irrigation. 14th AnnualJudd Hill Cotton Technology Field Day Tour Book, Trumann,Ark., Judd Hill Field Day Committee. 2008. (USDA,2008.) lTHE ANSWER(From Page 5, Do You Know…?) It was in 1983, after theMedfly crisis was over and it was feared that the public mightbecome complacent, assuming that the fruit fly danger hadpassed. The ad agency Foote, Cone & Belding/Honig and theL.A. County Ag Commissioner’s office joined in an L.A.-areacampaign aimed at mainland visitors to Hawaii. The artworkfeatured a smiling orange wearing sunglasses, and the slogan“Don’t Bug Me” was followed by the reminder to “have incomingfruit inspected… please.”34 Citrograph May/June 2013

Meet the faces of Dandy®citrus.For 85 years, Duda Farm Fresh Foods has been providing farm fresh fruits and vegetables to businesses and consumers.Our commitment to quality and availability holds true today now more than ever, as we aim to provide our customerswith a year-round supply of the most sought after citrus products. With a trusted network of growers, both domesticand international, Duda Farm Fresh Foods provides a consistent and high quality citrus supply all year long.Phone 559-627-1337Fax 559-627-3665www.DudaFresh.comJOIN OUR COMMUNITY.Dandy Fresh Fruits and Vegetables@Dandy_FreshdudafreshproduceMay/June 2013 Citrograph 35

IRRIGATIONTechnical and financial assistance from NRCSBrandon Bates and Marcos PerezThe USDA-Natural ResourcesConservation Service (NRCS)provides both technical andfinancial assistance for improving irrigation.This assistance can help make onfarmimprovements more economicallyfeasible and bring to light technologiesproven to benefit the land.For example, 40 years ago, NRCSin California invested in soil moisturesensors and demonstrated to growershow measuring soil moisture can helpconserve water. This technology hassince become more available to growers,and NRCS still provides technicaland financial assistance for those interestedin learning more.Also, NRCS gives financial assistancein those scenarios where changingirrigation systems will conserve water.In some cases this means changingfrom flood irrigation systems to micro/drip irrigation. In other cases, it maymean changing pumping systems tomore efficient means of pumping. Thisincludes variable frequency drives forelectrical pumps.NRCS conservation planners arehere to help. Growers are encouragedto discuss farm goals and improvementswith NRCS conservation planners.They will help show growers howNRCS can help them achieve theirgoals.The NRCS does not work alone.Partnerships between the NRCS andlocal farmers are critical to fulfillingthe NRCS vision of maintaininghealthy and productive lands. Localfarmers help guide how we do businessand what conservation practices areImportant dates:• National Water Quality Initiativeapplication deadline – July 12, 2013• Environmental Quality IncentivesPrograms 2014 applications due –Fall 2013• Conservation Technical Assistance –offered all year roundGo to www.usda.nrcs.gov.36 Citrograph May/June 2013most needed in the diverse landscapesacross California. For informationabout how to apply for programs orget involved, please contact your localUSDA Service Center. Service Centersmay be located online at http://offices.sc.egov.usda.gov.USDA: The People’s DepartmentWhat originally began as the SoilConservation Service in 1935 is nowknown as the Natural Resources ConservationService (NRCS), a namechange that highlights our broader missionof conservation. Bringing 60 yearsof scientific and technical expertise tothe conservation industry, we are involvedwith activities that help benefitsoil, water, plants, air, and animals.Photo courtesy of USDA NaturalResources Conservation Service.With 70% of U.S. land privatelyowned, partnership with private landownersis critical to the health of ournation’s land. By providing assistanceto these landowners, we help to cultivateproductive lands and healthy ecosystems.As part of the USDA, the NRCS isan agency committed to “helping peoplehelp the land”—our mission is toprovide resources to farmers and landownersto aid them with conservation.Ensuring productive lands in harmonywith a healthy environment is our priority.With operations in the UnitedStates, the Virgin Islands, Puerto Rico,and Guam, our agency touches thelives of a diverse range of individuals.NRCS employs approximately12,000 people in its 2,900 offices with90 percent working outside of Washington,D.C. We are in numerous com-munities across North America, workinghand-in-hand with landowners andour partners to improve our naturalresources. Our passion is derived fromstewardship of the land -- benefits weall enjoy, such as cleaner air and water,improved soil and abundant wildlifehabitat.ProgramsCTAConservation technical assistance(CTA) is the help NRCS and its partnersprovide to land users to addressopportunities, concerns, and problemsrelated to the use of natural resourcesand to help land users make soundnatural resource management decisionson private, tribal, and other nonfederallands.This assistance can help land users:• Maintain and improve privatelands and their management.• Implement better land managementtechnologies.• Protect and improve water qualityand quantity.• Maintain and improve wildlifeand fish habitat.• Enhance recreational opportunitieson their land.• Maintain and improve the aestheticcharacter of private land.• Explore opportunities to diversifyagricultural operations.• Develop and apply sustainableagricultural systems.This assistance may be in the formof resource assessment, practice design,resource monitoring, or follow-up ofinstalled practices.Although the CTA program doesnot include financial or cost-shareassistance, clients may develop conservationplans, which may serve as aspringboard for those interested in participatingin USDA financial assistanceprograms.CTA planning can also serve as adoor to financial assistance and easementconservation programs providedby other federal, state, and local programs.

EQIPEQIP is a continuous sign-up,voluntary, conservation program administeredby the Natural ResourcesConservation Service that providesfinancial and technical assistance forapproved conservation practices basedon a current conservation plan.The purposes of the EnvironmentalQuality Incentives Program (EQIP)is to promote agricultural production,forest management, and environmentalquality as compatible goals; optimizeenvironmental benefits; and helpfarmers and ranchers meet federal,state, tribal, and local environmentalregulations.NRCS encourages customers tosubmit an application at any time.EQIP applications are accepted on acontinuous basis with periodic applicationranking cutoffs when applicationsare ranked for funding. Applicationsreceived after the application rankingcutoff will be considered in the nextranking period.Interested applicants are encouragedto request conservation planningand technical assistance from a localNRCS field office to help with the developmentof a conservation plan. Aconservation plan is the basis for anEQIP application.OrganicHow the Organic Initiative works(smaller subhead)This assistance helps producersplan and implement conservation practicesto allow their organic operationsto be environmentally sustainable.Some highlights of the organic provisionsin the 2008 Farm Bill and requirementsfor participation in the programinclude:• Financial and technical assistanceto implement conservation practicesand planning related to addressing resourceconcerns associated with organicoperations.• Financial assistance is limited tototals of a maximum of $20,000 per fiscalyear AND no more than $80,000over a rolling six year Farm Bill forALL contracts approved through thisauthority.• Producers must meet all the othereligibility requirements associatedwith EQIP.• Participants are required developand work toward implementing an OrganicSystem Plan (OSP) to meet NationalOrganic Program certificationthrough USDA.2013 EQIP Organic InitiativeEach fiscal year, NRCS will focusfinancial and technical assistancethrough the EQIP Organic Initiative toapplicants who are:• Certified organic producers• Transitioning to organic production,or• Producers selling less than $5000organic products annuallyThe 2013 Organic Initiative providesfinancial assistance to implementCOME SEE WHAT WE'VE BEEN UP TO…“Visit our Website and see what's happening in the CitrusNursery World. Not only will you find Citrus Nursery News,Upcoming Events, and the latest Research Reports, but alsothe Citrus Nurseryman's ultimate resource, “THE BOOK”,which gives you everything you need to know aboutGovernment Agencies, Trade Information, Laws &Regulations, Pesticide Issues, a comprehensivelist of Industry Organizations and other CitrusNursery Resources. Please let us knowwhat you think!”a broad set of conservation practicesto assist organic producers meet theirresource concerns and fulfill many ofthe requirements in an Organic SystemPlan (OSP) including, but not limitedto, assistance with:• Developing a conservation plan.• Developing a transition to organicproduction plan.• Establishing boundaries and bufferzones.• Improving soil quality and organicmatter while minimizing erosion.• Improving pest management.• Developing a grazing plan andimproving grazing resources.• Improving waste utilization andcomposting.• Improving irrigation efficiency.• Enhancing cropping systems andnutrient management.Brandon Bates is the District Conservationistin the Bakersfield USDAService Center. Marcos Perez is the AgriculturalEngineer in the BakersfieldUSDA Service Center. lCITRUS – AVOCADOS – OLIVESContract Growingfor 2015onRich 16-6May/June 2013 Citrograph 37

ing how much the test company willcharge you and whether you will haveto provide funds in addition to the Programsubsidy.How to obtain a subsidized pumpefficiency testSubsidized pump efficiency testsare available, subject to budget availability,from APEP-approved participatingpump test companies.Important restrictions include:• Only one test is available perpump every 23 months.• The pump must be 25 horsepoweror greater.• In the case of a well, the pumptester must be able to measure thepumping water level.• Tests are not available for realestate transactions or to satisfy a mandateof any government or quasi-governmentagency.Other restrictions may apply.To obtain a pump test1. Contact the participating pumptest company of your choice to arrangea test. Log on to the Program web siteor call one of the Program offices listedat the end of this article if you need assistancein locating a test company.2. You will have to sign an AccessAgreement (granting legal access toyour pump) before the test and a Recordof Test (providing proof to theCalifornia Public Utilities Commissionthat the test was performed) after thetest.3. The tester will provide both youand the Program with a pump test report.You can discuss the results of thetest with the test company or Programpersonnel.4. The subsidy will be provided directlyto the test company by the Programand the test company will takecare of all other paperwork.How to apply for a cash incentive fora pump retrofitThe Program offers cash incentives,subject to budget availability, for retrofittingeligible pumps of any size to increaseefficiency. The incentive is basedon your annual energy use. The moreenergy you use, the larger the potentialincentive. However, the maximumincentive possible is 50 percent of theproject cost.Note these important program rules:• Only one incentive can be paidper individual pump in any one sixyearperiod.• A valid pump efficiency test mustbe performed before the retrofit projectis started and also after the projectis completed. These tests cannot bemore than three (3) years apart. Copiesof the test results must be submittedwith the application.• The post-project pump test mustbe performed within one (1) year ofthe project completion.• An application can be submittedfor a project that has already beenstarted or completed. However, an applicationpackage must be completedand approved within two (2) years ofproject completion.• Projects involving multiplepumping systems are not eligible forAPEP incentives. Contact APEP orPG&E to determine whether PG&Ehas other programs for which yourproject may be eligible.• The pump must be operational atthe time of retrofit.• The incentive cannot be combinedwith any other grant, incentive,SuperCitrus Trees559-592-2304Container grown ininsect resistant structuresUnique pot design growsmassive root systemDelivered in special “sock”for easy handlingNow taking orders for 2015Stronger Rootsmake SuperCitrus Treeswww.citrustreesource.comMay/June 2013 Citrograph 39

ebate, or service offered for the projectby one of the investor owned utilitiesor any state or local agency.Other restrictions may apply.If the Program has a copy of apump test done for your pump, we canprepare an application that is substantiallycomplete for you. All that will beneeded is your signature, informationon who will receive the incentive, andinformation regarding the retrofit performed.To participate1. Obtain an Application form byeither calling the Program office ordownloading a form from the Programweb site. Participating pump test companiesand many pump service companiesmay also have copies.2. Fill out the form as directedand submit to the main Program officealong with a copy of the pump efficiencytest performed before the retrofit.An Application can be submittedeither before or after the project hasbeen completed.3. The Program will review theApplication. They may ask for moreinformation and may recalculate theestimated incentive. The Program willnotify you when it is approved, andyour estimated incentive amount.4. If the Application is being submittedbefore the project is complete,you must notify the Program when theproject is finished and submit requireddocumentation. The Program will verifyall information, may recalculate theincentive based on the post-test, andwill inform you when the Applicationis fully approved.APEP can help you to minimizeyour pumping costsThe Advanced Pumping EfficiencyProgram can help you improve overallpump efficiency and save energy. Weare here to help every step of the way.APEP maintains regional offices inNorthern California, the San JoaquinValley, and the Central Coast. Log onto the web site at www.pumpefficiency.org. Here you will find summaries ofall Program components, a calendarof upcoming events, application forms,phone numbers and e-mail addressesof the regional offices, and a knowledge-baseto help you conserve energyand water.Contact us to see how a pump efficiencytest can provide you with thecritical information required to makea decision as to a retrofit. Applying forthe retrofit incentive is easy and we arehere to help every step of the way.• Northern California regional office(559) 260-6148.• San Joaquin Valley (main office)(800) 845-6038, fax to (559) 278-2998.• Central Coast regional office(San Mateo County to Ventura County)(805) 709-4180, fax to (805) 619-7506.Or, call your PG&E account representative.The Center for Irrigation Technology( CIT) is an independent testinglaboratory, applied research facility,and educational resource center basedat California State University, Fresno.CIT is dedicated to advancing watermanagement practices and irrigationtechnology with programs in four majorareas: hydraulics laboratory testing,field research, analytical studies andspecial projects, and education. Visitwww.fresnostate.edu/jcast/cit/. lTier 4 Available!New LectroBlast Tower – Increase yourtotal coverage and efficiency.Progressive Ag Inc.1336 McWilliams Way, Modesto, CA 95351209-567-3232 • www.proaginc.com • 800-351-810140 Citrograph May/June 2013

May/June 2013 Citrograph 41

Best in class.Only REGALIA ® will make you go back to the blackboard when choosing your best fungicide program.It offers the same top-notch disease control as old-school chemistry, but with all the benefits of a newschoolbiological solution. Soil or foliar – it all adds up to best-in-class for fruit, nuts and vegetables.See your retailer today. Go to www.marronebio.com/regalia for more.Always read and follow label directions. ©2013 Marrone Bio Innovations, Inc. All rights reserved. Regalia, the Regalia logo, Marrone Bio Innovations, and theMarrone Bio Innovations logo are registered trademarks of Marrone Bio Innovations, Inc. U.S. Patent No. 4,863,734 and 5,989,429. Additional patents pending. 12/12-19203

John has always been eager to understand new scientific discovery and learn howto apply it to his field of expertise in a manner that laymen could understand.elor of Science degree in soil science in 1951.At UC, he had studied under some of the great soils professorsand scholars, so he was well prepared for his first workexperience in 1951 as a soils technician mapping soils in theSan Joaquin Valley. He spent many long days in the field layingout grids and then pounding a soil tube into the groundto obtain samples for future analysis and classification for thepreparation of the maps we use today in agriculture.In May of 1953, John began his career with the Universityof California Cooperative Extension Service as a farmadvisor in Orange County, where he soon met his futurewife, Mary Beth. They were married the next year.In the years that followed, three children were born toJohn and Mary Beth -- Karen, who is a high school Englishteacher, John R., an environmental engineer, and David, anengineer specializing in aerodynamics.John worked as an advisor in the Orange County officeuntil 1966, when he moved to the Tulare County CooperativeExtension office as the citrus farm advisor. In June of1980, he moved to the University’s Kearney Research andExtension Center as the subtropical horticultural specialist.Desiring to be closer to the citrus belt, John requested transferto the University’s Lindcove Research and ExtensionCenter, arriving at LREC in 1982. He remained based at theLindcove field station until his retirement in 1991.While John worked for the UC Cooperative ExtensionService, he was quite active in community affairs as a schoolboard member for the Exeter elementary school, as a boardmember to the Exeter Presbyterian Church, a member ofthe Exeter Kiwanis Club and a participating member of theGiant Oaks Barbershop Choral Group.Expert at dissecting problemsThe many citrus growers who called John for his adviceor had him make a farm call to look at a problem are alwaysquick to tell you how he could dissect a problem, whetherit be a soils, rootstock, fertility, entomological or irrigationproblem, and provide them with meaningful answers thatwere scientifically based and recommend solutionsto the existing problem.John has always been eager to understandnew scientific discovery -- maintaining goodcontact with principal researchers -- and learnhow to apply it to his field of expertise in amanner that laymen could understand. That’sthe true calling of a farm advisor, to be a masterteacher.These teaching skills were always evident inthe content and preparation that John put intohis Citrus Field Days or Citrus Meeting andwere certainly apparent as John became an area-wideCitrus Specialist working with the farmadvisors responsible for citrus crops in his area.In addition to his teaching, John was agifted researcher. The citrus industry was therecipient of his extensive research activities.His educational background made himuniquely qualified to address a radical changein water management. The change was the conceptof applying irrigation water in small volumeson a very frequent basis by means of microsprinklers.At the same time, he addresseda related concept that the water requirementsof an orchard could be estimated based uponthe size of the tree canopy and current weatherconditions and allow a person to accuratelyschedule irrigation based upon this estimate.This faded newspaper clipping is from a 1961 article in the Orange CountyRegister reporting on “orange trees being hit by quick decline.”Integrating new irrigation conceptsJohn conducted extensive research integratingthe two concepts into a practical watermanagement plan for the industry. Water applicationcould be much more precise with microsprinklersand utilizing ET. John developed44 Citrograph May/June 2013

At a field meeting at Lindcove in 1985, Pehrson discusses histrials with ‘Flying Dragon’ rootstock.pened to be ‘in the right place at the right time,’ as he putit, to do some things that were very meaningful to him bothpersonally and professionally.“For one, he was able to provide some very helpful informationand guidance to growers who were losing theirorchards to urbanization and struggling with their decisionsabout whether to plant citrus somewhere else and wherethey should go.“He talked about a number of aspects of his work thatwere interesting and fulfilling, both in Southern Californiaand in the San Joaquin Valley, but then he zeroed-in onsomething that he obviously feels especially good about.He said, ‘Probably the thing I’m most pleased about wasthat I was able to take the research done by Embleton andJones on citrus nutrition and introduce the Orange Countygrowers to the concept of leaf analysis as your guide to fertilization.Everything that Embleton and Jones had doneshowed that the right amount of nitrogen gave you qualityfruit, whereas luxury levels of nitrogen gave you regreeningand coarseness, and other problems.’“One thing in particular really brought a smile to his facewhen he was talking about Central California, and that washis role in making growers aware of the ‘Lane Late’ navel.Bill Bitters, who was known for not writing up his research,had included Lane Late in a navel strain trial at the Lindcovestation, John said, ‘and it had just sat there.’“He said, ‘Discussions were going on about what to dowith that plot since Bitters was retired and they couldn’tkeep those trees going forever. So, we decided to hold a FieldDay so growers could take a look. We thought they wouldThe many hats of John PehrsonAs others have related, John was a man of manytalents; he even sang in a barbershop quartet. In otherwords, he wore many hats. But he also owned many hats,and it became a point of interest to see which he wouldchoose to wear to certain occasions.He had everything -- slouch hats in many colors,jaunty English tweed hats, straw hats, warm wintery caps,and big sun-protective hats. Although I don’t rememberhim ever wearing one, he probably even had a cowboyhat or two.At John’s retirement, the Citrus Men’s Club held aluncheon in his honor, and the invitation was illustratedwith hats, hats and more hats. -- Agriculture communicationsspecialist Shirley Kirkpatrickbe really interested in the early group of navels, but lo andbehold, as the discussions went on, people were asking whatabout this Lane Late; it’s holding up differently than others.So we had a few more events where we put Lane Late outfor people’s perusal’.”A. G. Salter AwardIn 1994, the California Citrus Quality Council (CCQC)presented Pehrson with the industry’s most prestigious prize,the Albert G. Salter Memorial Award. The inscription on theplaque read:In recognition of his long, dedicated and consummatelyeffective career in serving the citrus industry of California asa reliable and respected source of information and practicalguidance for citrus growers in the San Joaquin Valley, and interimlyin Orange County.Over a span of forty years in variousassignments within the University of California farm advisorsservices he came to epitomize the ideal of being a readySHUR FARMS® COLD AIR DRAINRENTAL UNITS NOW AVAILABLERESERVE YOURS TODAYLIMITED AVAILABILITYTo order, call or emailSHuR FARMS® Frost ProtectionPhone: 909.825.2035 • Fax: 909.825.2611info@shurfarms.com • www.shurfarms.comManufacturer of the world’s most advanced frost protection systemsLike father, like son. Young John R. Pehrson getting a lessonin planting an orange tree from his dad, John Pehrson, Jr., inthis 1958 photo taken in Santa Ana. Pehrson family album.46 Citrograph May/June 2013

source of state-of-the-art information about citricultural practicesand seasoned counseling while conjunctively providingsignificant leadership in problem-solving research at the fieldlevel, coupled with the helpful summarization and disseminationof all relevant research findings.This past summer, with Mary Beth in failing health,they decided to relocate to Southern California to be closerto their children. But before that latest move, they werehappily residing in a senior living complex in Visalia, whereit was understood that John was the resident scientist willingto hold a seminar on almost any scientific subject fromspace travel and astronomy to the water problems of thestate of California, applying the same teaching techniqueshe used so successfully in his career.John will always be a teacher.Ray Copeland was the Superintendent of the Universityof California’s Lindcove Research and Extension Centerfrom 1965 through 1986. Most recently, until his retirementin September 2012, Copeland was president of Biagro WesternSales in Visalia. He is a hands-on grower who, along witha business partner, produces navels, Valencias, lemons, mandarins,and olives in Tulare County. Neil O’Connell has beena UC Cooperative Extension farm advisor in Tulare Countysince 1981, dealing exclusively with citrus and avocados. lPACIFIC DISTRIBUTING, INCDistributor forOrchard-Rite®wind machines forfrost protection &Tropic Breeze®original partsSalesServiceNewUsedPortableStationary24 HourEmergencyService559-564-3114Woodlake, CAwww.orchard-rite.comRandy Quenzer, Sales559-805-8254randyquenzer@pdi-wind.comJeff Thorning, Sales559-972-9937jeffthorning@pdi-wind.comMay/June 2013 Citrograph 47

used for molecular phylogenetics to confirm the identities ofthese fungi.Similarly for fungi belonging to the Diatrypaceae, theITS region and a portion of the b-tubulin gene were used inthe phylogenetic analysis.To determine the pathogenicity of selected fungi, detachedgreen shoots of ‘Allen Eureka’ lemon were stemwoundinoculated by removing a piece of cambium with acork-borer and then placing agar plugs infested with oneisolate of representative fungi on the wound. Control shootswere inoculated with uninfested agar plugs.Shoots were incubated at 258C under humid conditionsfor two weeks. Resulting lesions were measured and isolationswere made from these shoots to confirm pathogenicity.Results and future outlookSurveys conducted throughout the southern Californiadesert regions revealed the predominate fungi associatedwith citrus branch canker and dieback are a Neoscytalidiumspecies as well as three distinct Eutypella species based onmorphology (Figure 1). These fungi have been detected inall three previously mentioned counties and can be foundassociated with both lemon and grapefruit trees.Symptoms frequently observed included cankers --which ranged in color from gray, chocolate brown to black-- splitting of the bark often accompanied by gum exudation,sloughing off of bark revealing a layer of black fungal sporesunderneath, and progressive dieback (Figure 2).Samples collected from other woody hosts surroundingcitrus groves, for example Tamarix, also show an associationof Eutypella spp. with symptoms of branch canker anddieback; however, it is unknown if Eutypella is the cause ofdieback on Tamarix. The Neoscytalidium sp. is the most commoncanker fungus isolated from symptomatic tissues.Throughout this survey, numerous perithecia of Eutypellawere observed on dead branches. These fungi were foundPhylogenetic(s) – refers simply to the relationshipamong organisms inferred through an observable characteristic.In this study, DNA sequences of unknownfungi were compared to those of known fungi in order todetermine fungal identity.Morphological – refers to the physical characteristics(color, shape, size, etc.) of an organism.Perithecia – flask shaped structure that contains sexualfungal spores (ascospores).associated with all varieties of citrus that have been sampledand all ages of trees are presumed to be susceptible to infectionby these fungal species (Table 1).Phylogenetic analysis supports our morphologicalidentification and confirms that the species Neoscytalidiumdimidiatum causes the disease known as Hendersonula.These analyses also confirm two of the Eutypella spp. as E. cit-A B CD E FFigure 2. Photographs of various symptoms of citrus branch canker and dieback: (A) citrus tree in a commercial groveshowing signs of dieback (red arrow); (B) branch of lemon showing bark peeling. Underneath the bark, fungal spores ofNeoscytalidium can be seen as a black powdery mass; (C) cross section of a branch showing the brown necrotic canker (redarrow); (D) lemon tree and Tamarix (on the right) showing signs of dieback (red arrows); (E) branch showing bark splittingand exudation of gum; (F) cross section of cankered branch of Tamarix from photo D. Red arrow points to canker.May/June 2013 Citrograph 49

icola and E. microtheca. The thirdEutypella species remains unidentifiedat this time, but phylogeneticanalysis shows it is closely relatedto Peroneutypa scoparia, formerlyEutypella scoparia. Future workwill be aimed at determining theidentity of this Eutypella species.Based on the results of the detachedshoot assay (Figure 3), E.microtheca and Eutypella sp. arepathogenic on citrus as both wereable to produce lesions (~10mm)and could be isolated from inoculatedshoots; however, E. citricolafailed to produce lesions and couldnot be recovered from inoculatedshoots. N. dimidiatum producedthe largest lesions (~60mm) andwas included in this experimentfor comparative purposes eventhough it was reported as a pathogenof citrus in previous studies.Statistical analysis was conductedto compare mean lesionlengths, and these results suggestthat Eutypella spp. poses a low tomoderate virulence in comparisonto N. dimidiatum, as lesions causedby Eutypella spp. were not statisticallydifferent from the negative/healthy control.It is necessary, however, to further explore the role ofEutypella spp. as pathogens of citrus and grapevine, particularlyin regions where these two commodities are grown inclose proximity.For example, the predominance of Eutypella in theCoachella Valley region likely suggests an adaptation to theclimate of these regions which experience wide fluctuationsin temperature.Results from a growth rate assay of fungi in differenttemperatures reveal optimal growth temperatures for bothN. dimidiatum and Eutypella spp. to be between 308C and358C (Figure 4). Studies are underway to explore the effectof temperature on disease expression and development.Mean External Lesion Length (mm)80706050403020100N. E.citricola E. Eutypella sp. ControldimidatummicrothecaFigure 3. Mean external lesion lengths on inoculated greenshoots of ‘Allen Eureka’ lemon. Asterisk denotes means thatare significantly different at p=0.05.50 Citrograph May/June 2013Table 1: Representative Neoscytalidium and Eutypellaisolates collected from this studySpecies Strain County Host VarietyNeoscytalidium DC08 Imperial Citrus paradisi Rio ReddimidiatumN. dimidiatum DC29 Imperial Citrus paradisi Rio RedN. dimidiatum DC132 Riverside Citrus limon Allen EurekaN. dimidiatum DC173 Imperial Citrus limon LisbonN. dimidiatum DC176 Imperial Citrus paradisi Rio RedEutypella citricola DC83 Riverside Citrus limon Allen EurekaE. citricola DC91 Imperial Citrus paradisi Rio RedE. citricola DC113 Imperial Citrus paradisi Rio RedE. citricola DC117 Imperial Citrus paradisi Rio RedE. citricola DC186 Imperial Citrus paradisi RubyE. citricola DC272 San Diego Citrus limon LisbonE. citricola DC291 San Diego Tamarix sp. –E. citricola DC293 San Diego Citrus limon LisbonEutypella microtheca DC09 Imperial Citrus paradisi Rio RedE. microtheca DC37 Imperial Citrus paradisi Rio RedE. microtheca DC148 Imperial Citrus limon LisbonEutypella sp. DC210 Imperial Citrus paradisi RubyEutypella sp. DC211 Imperial Citrus paradisi RubyEutypella sp. DC276 San Diego Citrus limon LisbonEutypella sp. DC287 San Diego Tamarix sp. –Additionally, studies are being planned to investigatethe interaction between N. dimidiatum and Eutypella spp. Ina few cases, both N. dimidiatum and Eutypella spp. could beisolated from the same diseased branch sample, raising questionsregarding the interaction of these two fungi.The nature of this interaction is unknown, but of particularinterest is whether or not this interaction has any effecton disease development. If a degree of antagonism exists betweenNeoscytalidium and Eutypella, then it is possible thatcolonization of the plant by one fungus could preclude or atleast limit later colonization of the plant by the other fungus.Conversely, these two fungi could act together to produce agreater degree of disease than either one individually.These greenhouse and field studies will aid in better understandingthe role of these fungi in the overall dieback ofcitrus in this region.Management of this disease is currently under investigation,but growers are advised to maintain good culturalpractices to ensure proper grove hygiene. These practicesinclude: avoiding excessive pruning/mechanical damage, asopen wounds serve as infection sites for these pathogens; removingdiseased branches and properly disposing of them;and, disinfecting contaminated tools so as to reduce the riskof spreading the pathogen.In cases where branch canker and dieback are severe,growers may benefit from the use of chemical applications.Efforts are being made to screen commercial fungicides currentlyon the market that may be efficacious in the controlof these pathogens. Initial results from an in vitro fungicide

Average daily growth (mm)403530252015105Neoscytalidium dimidiatumEutypella microtecaEutypella citricolaEutypella scoparia05 10 15 20 25 30 35 40Temperature °CFigure 4. The growth rate of fungi in different temperatures.screen show that a number of commercial products currentlyregistered on citrus are capable of reducing fungal growth,some of which are highly effective at very low concentrations.Field studies will be necessary to evaluate fungicide efficacyand appropriate application methods. These results willbe made available to growers through the UC IPM onlinewebsite (http://www.ipm.ucdavis.edu).Taken together, these results underscore the need forfurther investigation into this unique disease complex facedby desert growers. Conclusion of these studies will providethe industry with the appropriate management strategiesto maintain lucrative production in this area.Project leader Dr. Akif Eskalen is Assistant CooperativeExtension Specialist and Plant Pathologist, Joey S.Mayorquin is a graduate student, and Danny H. Wang is aLaboratory Assistant in the Department of Plant Pathologyand Microbiology at the University of California Riverside.Joe Barcinas is a grower and pest control advisor. Dr. GaryBender is a UCCE Farm Advisor in San Diego County.CRB research project reference number 5400-140.Additional readingAdesemoye, A. and A. Eskalen. First report of Eutypellaspp. associated with branch canker of citrus in California. PlantDisease. 95.9 (2011): 1187Adesemoye, A. O., Mayorquin, J.S., Wang, D.H., Twizeyimana,M., Lynch, S.C., and A. Eskalen. Identification of speciesof Botryosphaeriaceae causing cankers in citrus in California.Plant Disease. Submitted.Calavan, E C and J M Wallace. Hendersonula toruloideaNattrass on citrus in California. Phytopathology. 44 (1954): 635Crous, P.W., Slippers, B., Wingfield, M.J., Rheeder, J., Marasas,W.F.O., Phillips, A.J.L, Alves, A., Burgess, T., Barber, P., andJ.Z. Groenewald. Phylogenetic lineages in the Botryosphaeriaceae.Studies in Mycology. 55 (2006): 235Trouillas FP, Urbez-Torres JR, and W.D.Gubler. Diversityof diatrypaceous fungi associated with grapevine canker diseasesin California. Mycologia. 102(2) (2010):319 lTreesAvailable!This Year2013– de Nules CRZ– Tango C35– Cara Cara R16Next Year2014– de Nules CRZ– Tango C35– Miho Wase CRZ– Gold Nugget C35...and many more!The BurchellNursery INc.559-834-1661www.burchellnursery.comENTOMOLOGICAL SERVICES, INC.Citrus and Subtropical SpecialistBiologically Intensive Pest ManagementExperienced Entomologists75+ combined years of AphytisSuccess in the San Jaoquin ValleyWWW.APHYTIS.COMcitrusIPM@gmail.comPO Box 3043Visalia, CA 93278-3043Phone: (559) 627-1153Fax: (559) 635-495516120 Krameria Ave.Riverside, CA 92054(951) 285-5437May/June 2013 Citrograph 51

Azoxystrobin, fludioxonil, and pyrimethanilare mostly effective againstPenicillium decays, especially P. digitatum,the most important postharvestdecays of citrus in semi-arid climateslike California. Potassium phosphiteis the first postharvest fungicide registeredfor management of Phytophthorabrown rot.Some of these new fungicides suchas azoxystrobin will only be availablein pre-mixtures with other fungicides;others will also be marketed bythemselves. Currently registered premixturesinclude imazalil/pyrimethanil(Philabuster) and azoxystrobin/fludioxonil (Graduate A+). Additionalpre-mixtures are in development (Figure1). Graduate Max is a multi-packof fludioxonil and thiabendazole.Although the new fungicides wereproven to be highly effective in numerousstudies and they have domestic tolerancesand registrations, actual commercialuse of some of them has beenlimited to date. This is because maximumresidue limits (MRLs) have notbeen established in some of the majorexport markets, and fruit treated withthese fungicides can only be marketeddomestically. Potassium phosphite isexempt from residues in the UnitedStates, but not in many other countries.Overcoming these limitations inthe use of new postharvest fungicidesis a major effort that demands the coordinatedeffort of researchers, citrusindustry representatives, the chemicalindustry, and national and internationalregulatory agencies.Obtaining the food additive tolerance(FAT) for fludioxonil in Japan in2011 and for azoxystrobin (pending) in2013 are major breakthroughs in internationaltrade of California citrus. Currentlyimazalil, TBZ, and SOPP are theonly other fungicidal compounds thathave FAT status in Japan.Over the years, our program hasbeen instrumental in many aspects ofpostharvest fungicide development forcitrus. We conducted studies for optimizingtreatment efficacy and providedinformation on best usage strategies.In this article, we provide updateson the management of green moldand sour rot with the new postharvestfungicides azoxystrobin/fludioxonil(Graduate A+), fludioxonil/TBZ(Graduate Max MP), and propiconazole(Mentor) as well as on new post-Fig. 1. Postharvest fungicide mixtures and pre-mixtures registered or indevelopment for citrus.Fig. 2. Fungicide application methods on an experimental packingline. A. Recirculating,in-line aqueous fungicide drench. Delivery pipe across the top pours thefungicide suspension into a distribution pan that allows the fungicide stream overthe passing fruit rotating on a PVC roller bed. Fungicide is collected below therollers and returned to the fungicide reservoir (not shown). B. Controlled dropletapplication (CDA) of fungicide-fruit coating mixtures to fruit that are moved onthe active rollers and conveyed down the roller bed.May/June 2013 Citrograph 53

harvest treatments for management ofPhytophthora brown rot.Management of green mold and sourrotIn an advanced stage of developmentof fludioxonil and azoxystrobin,Graduate A+ (a pre-mixture of bothfungicides) was evaluated and comparedto imazalil in a commercial packinghousestudy.For this, aqueous in-line drenchand low volume, controlled droplet(CDA) systems were utilized in thesequential application of fungicides(Figure 2A, B). Fungicides were mixedwith a commercial packing fruit coating(pack wax) for the CDA system.Multiple lines were utilized for eachbase fungicide (e.g., either imazalil orfludioxonil) to prevent cross contaminationof fungicides on the inoculatedlemon and orange fruit.These studies demonstrated thehigh efficacy of Graduate A+ appliedin a pack wax using a CDA system thatwas similar to the industry standardimazalil on lemons (Figures 3, 4). Theefficacy of the fungicides was significantlyincreased by using an aqueous,in-line drench prior to the CDA applicationthat resulted in zero or near-zerolevels of decay on lemons and oranges.Graduate A+ – FRAC Groups11/12 and the mixture of imazalil andpyrimethanil – FRAC Groups 3/9 (similarto Philabuster) have two active ingredientsthat have different modes ofaction on the pathogen and providedthe highest performance of the treatmentsand resistance management ascompared to when using single activeingredients.Fig. 3. Green mold of lemons. A. Inoculated, untreated fruit showing whitemycelium and green sporulation. B and C. Inoculated fruit treated with imazalil/pyrimethanil or fludioxonil/azoxystrobin (Graduate A+), respectively.Graduate A+ was applied at afraction of the rate of imazalil in thewax treatment. On oranges, the performanceof Graduate A+ was lowerthan for imazalil when applied only asa CDA-wax treatment. This indicatedthat Graduate A+ was possibly boundby the wax and prevented the fungicidefrom inhibiting the pathogen’s growthwhen fruit were inoculated 16 hoursprior to treatment.For sporulation control, the activityof Graduate A+ was comparable toimazalil considering that a highly sensitiveisolate was used, and a sporulationrating of 1 on a scale of 0 to 4. This indicatedthat sporulation was inhibited onover 90% of the fruit surface.In numerous postharvest fruit inoculationstudies, we previously identifiedpropiconazole as one of the mosteffective fungicides against sour rot(Figure 5). Propiconazole can be alsoused for controlling Penicillium decays,similar to imazalil. With greatersafety standards than imazalil, it maypotentially replace imazalil as the representativeDMI for postharvest use oncitrus. Propiconazole can be effectivelyused in integrated decay managementprograms because it is compatible withchlorine (at 100 mg/L) and sodium bicarbonate(at 2%).In an experimental packinglinestudy, we evaluated the comparativeefficacy of propiconazole and new formulationsof SOPP and OPP (providedby UPI-Decco) against sour rot; the efficacyas aqueous, storage wax, and dualtreatments applied sequentially on aPVC-roller bed; as well as the efficacyof propiconazole-SOPP/OPP combinationtreatments. Lemon fruit wereinoculated with G. citri-aurantii andtreated after 18 hours. Aqueous treatmentswere applied as high-volume,in-line drench applications, whereasstorage wax treatments were applied aslow-volume spray applications.The results presented in Figure 6indicate that the efficacy of propiconazole(Mentor) was significantly higherFig. 4. Commercial packinghouse study for the management of green mold.Treatments were applied 10 to 16 hours after wound-inoculation (flavedoinjury) with an imazalil-sensitive isolate of Penicillium digitatum. Forevaluation of sporulation control, a separate set of fruit was inoculated at thecenter. Fludioxonil/azoxystrobin treatments were applied using Graduate A+.54 Citrograph May/June 2013

than that of SOPP or OPP and thata combination treatment of the twofungicides did not provide a benefit ascompared to propiconazole alone.Additionally, propiconazole wasmost effective when applied as anaqueous treatment, and the efficacywas significantly reduced when appliedin storage wax. An aqueous drench applicationof propiconazole followed bya spray application of the fungicide instorage wax did not provide additionalbenefits in decay control but it wasbeneficial for sporulation control ofPenicillium decays.In a study on green mold and sourrot, we evaluated the comparative efficacyof propiconazole, imazalil, a mixtureof fludioxonil and TBZ, as well asa mixture and a new pre-mixture offludioxonil and propiconazole on lemonand orange fruit that were inoculatedwith imazalil-sensitive and -resistantisolates of Penicillium digitatum andwith G. citri-aurantii.Re-circulating aqueous drench applicationswere used in this study, andfungicide treatments were followedby a storage fruit coating low-volumespray application.Propiconazole and imazalil did notreduce the incidence of green moldwhen using the imazalil-resistant isolate(cross-resistance), but the mixtureand pre-mixture of propiconazole andfludioxonil effectively reduced decaycaused by both isolates on lemon andoranges (Figure 7A). The fludioxonil-TBZ mixture was also effective. Sourrot was reduced to very low levels byall treatments that contained propiconazole,and there was no negative interactionbetween fungicides (Figure 7B).These studies also demonstratethat in-line, recirculating drenches arean excellent application strategy thatoptimizes decay control.Propiconazole is currently beingregistered on citrus, stone fruit, and tomatocrops for the management of sourrot and other decays. On citrus it is alreadyfederally registered with Californiastate registration pending.These studies were also targeted towardthe planned development of newmixtures and pre-mixtures (see Figure1). Our data indicate that mixtures offludioxonil and TBZ or of fludioxoniland propiconazole are highly effectiveagainst green mold caused byDMI-sensitive and resistant isolatesFig. 5. Sour rot of lemons. A. Natural incidence of decay showing “melting” ofdecayed fruit; B. Inoculated, untreated fruit showing lesions with water-soakedmargins and white mycelial growth in the center; C. Inoculated fruit treated withpropiconazole show little to no decay. Note for inoculated fruit, black lines onfruit indicate inoculation sites.of the pathogen. The latter mixtureis also effective against sour rot. Theplanned triple mixture of fludioxonil,azoxystrobin, and propiconazole ora tank mixture of the first two fungicidesand imazalil will also be effectiveagainst the two decays, but has built-inresistance management with two components(i.e., fludioxonil and azoxystrobin)active against imazalil-resistantstrains of P. digitatum.This built-in resistance managementof pre-mixtures can be describedbased on the natural resistance frequenciesthat are inherent to any fungicide-pathogeninteraction and thatvary among fungicides and pathogensinvolved.For example, resistance frequenciesin natural populations of P. digitatumto fludioxonil and pyrimethanilwere calculated by us as 9.5 x 10 -7 to 1.5x 10 -6 and 7.3 x 10 -6 to 6.2 x 10 -5 , respectively.This implies that resistance frequenciesof a fludioxonil-pyrimethanilmixture would be approximately 7 x10 -12 to 9 x 10 -11 .These numbers seem very low, butconsidering the enormous spore productionpotential of Penicillium species,resistance development is still likely tooccur if the full spectrum of anti-resistancestrategies is not employed.Management of brown rotBrown rot of citrus fruit is causedby species of Phytophthora including P.citrophthora, P. syringae, P. parasitica,and P. hibernalis. The disease commonlyoccurs in California during the winterFig. 6. Evaluation of postharvest fungicides in an experimental packingline studyfor management of sour rot of lemons. Fruit were treated 18 hours after woundinoculationwith G. citri-aurantii.May/June 2013 Citrograph 55

season when high rainfall may occur.Although losses may occur in theorchard, the most serious aspect of thedisease involves mixing symptomless,infected fruit at harvest with healthyfruit. Decay may then spread quicklyfrom fruit to fruit in storage and duringtransit, and a large number of fruit maybecome affected.Preharvest treatments with copperor other fungicides can be done,but no postharvest treatments withinternational tolerances are currentlyavailable. Phosphonate fungicides haveexempt status in the United States, andseveral formulations have postharvestregistrations. These could be especiallyvaluable when preharvest copper treatmentswere not applied. Thus, we initiatedstudies on the evaluation of newpostharvest treatments that includedpotassium phosphite, mandipropamid(Revus), fluopicolide (Presidio), andazoxystrobin.Orange fruit were inoculated withzoospores of P. citrophthora and treatedwith aqueous solutions of the fungicidesafter 12 hours (post-infection activity),or treated fruit were inoculatedafter 24 hours (pre-infection activity).In these postharvest studies, alltreatments evaluated were highly effectiveas pre-infection treatments (Figure8; data for azoxystrobin not shown).Potassium phosphite and fluopicolide,but not mandipropamid, were alsoeffective as post-infection treatmentsand, thus, these could be used to preventdecay from pre-existing infectionsthat occur before harvest in the orchard.Potassium phosphite, when used ata rate of 900 mg/L, demonstrated excellentpost-infection activity even whenfruit were treated 18 hours after inoculation.Thus, if no protective field applicationsare done, fruit harvested afteran infection period can still be protectedfrom brown rot by postharvesttreatments with potassium phosphite.Still, postharvest treatments withmandipropamid or azoxystrobin thatdemonstrated no post-infection activityin these experiments could stillbe beneficial because new infectionsfrom contact with diseased fruit canbe prevented.For the integration of potassiumphosphite into current postharvesttreatment strategies that include themanagement of other decays, we conductedstudies on the interaction ofpotassium phosphite with registeredpostharvest fungicides.For this, the efficacy in reducingbrown rot and green mold of mixtureFig. 7 Evaluation of postharvest fungicides in an experimental packingline studyusing in-line recirculating drench applications of inoculated fruit for managementof green mold.Table 2. Interaction of potassium phosphite withselected Table 2. Interaction registered of potassium postharvest phosphite with fungicides selected registered formanagementpostharvest fungicidesofforgreenmanagementmoldofandgreenbrownmold androt.brown rot.Fig. 8. Evaluation of new postharvest treatments formanagement of Phytophthora brown rot of navel orangefruit.Mixtures Brown rot Green MoldPotassium phosphite -ImazalilNo interaction No interactionPotassium phosphite -Graduate A+Negative Interaction* No interactionPotassium phosphite -PenbotecVariableVariablePotassium phosphite -sodium bicarbonateVariableNot done* - A negative interaction indicates a decrease in efficacy. Potassium phosphitewas used at 900 mg/L whereas the other fungicides were used at labeled rates.56 Citrograph May/June 2013

treatments was compared with single-fungicide applications.The results are summarized in Table 2 and indicate that potassiumphosphite in some cases had no effect on the efficacy ofother fungicides, sometimes effects were variable, and sometimesthe efficacy of other fungicides was decreased. Negativeinteractions, however, were considered of minor impact andmay not be noticeable under commercial conditions becausehighly favorable conditions for disease development wereused in the studies we conducted.As indicated above, potassium phosphite has an exemptstatus in the United States but not in many export markets. Thecompound is labeled for use against green mold and brown rot.Rates required to obtain a reduction in green mold, however,are extremely high (i.e., 8,000 to 12,000 mg/L) compared torates needed for brown rot management (i.e., 600 to 900 mg/L).Efforts are underway for registration of potassium and calciumphosphites through the IR-4 program to establish internationalMRLs with our trade partners.Additionally, we were successful in requesting a pre- andpostharvest registration of fluopicolide (Presidio) for use oncitrus for managing Phytophthora root rot in the orchard andbrown rot of fruit in the orchard and during storage, transportation,and marketing.We also recommend mandipropamid (Revus) for preandpostharvest use on citrus, and acceptance into the IR-4program is pending for the 2013 cycle. These materials wereselected because they have different modes of action againstthe pathogens. Fluopicolide, mandipropamid, and the phosphonatesbelong to FRAC groups 43, 40, and 33, respectively.continued on p. 58When was the lasttime you reviewedyour farm insurancecoverage?Let us do a free review for you.We specialize in agriculturerelated business insurance.Crop - Farm - SprayCommercial AgWorkers CompGroup MedicalCall David or Rob559-594-5500nielseninsurance.net502-A North Kaweah (Hwy 65)Exeter CA 93221 Lic # 0705090May/June 2013 Citrograph 57

Registrations of several fungicideswill ensure that resistance managementstrategies such as rotations or mixturescan be implemented to ensure the longtermusage of these compounds.ConclusionsThe development of postharvestfungicide treatments for managing decaysof citrus fruit requires a constanteffort due to the ongoing necessity toidentify effective fungicides often fromnumbered products, develop usagestrategies of these products based ontheir chemical characteristics, establishtolerances for domestic use, work withour international trade partners to establishMRLs, and to develop resistancemanagement practices that ensure thelong-term usage of registered materials.This effort not only prevents croploss but allows new strategies for marketingfruit and allows the fresh marketcitrus industry to have products availablethat can manage indigenous andpotentially invasive pathogens that areintroduced.Furthermore, having multipleproducts allows the industry to respondto quarantine issues for diseasesof concern to our trade partners. Thisagain will allow the industry to respondto maintain un-interrupted marketingof fruit that is vital to the long-term financialhealth of the industry.Following this model for the developmentof postharvest treatments formanaging fruit decays, we have beensuccessful in registering several newproducts that are highly effective inpreventing Penicillium, brown rot, andsour rot decays. Furthermore, with therecent and ongoing establishment ofMRLs with our major trade partners,the fresh market citrus industry is onthe horizon of a new era in postharvestdecay management.AcknowledgementsThe authors thank Syngenta CropProtection, Janssen Pharmaceutical,and Decco Postharvest for providingfungicides used in these studies, recognizethe outstanding assistance ofReach Commercial California& Arizona Citrus GrowersWhether you're selling tractors or other farm equipment,pickup trucks,irrigation equipment, fertilizer or pesticides...consider the value of yourad dollar in the pages of Citrograph.Each issue reaches every commercial citrus grower in the statesof California and Arizona, plus associated business membersaffiliated with the citrus industry...the people in charge ofpurchasing. Your advertising message is directed to farmleaders who use vast amounts of goods and services.Circulation reaches over 5,000 key decision makers amongCalifornia and Arizona fresh citrus growers, landowners andindustry-involved companies. In the near future, Citrographwill reach the entire United States.Mark Ryckman of Progressive Ag, Inc. was leery about advertising. “I have triedmagazine advertising in the past, along with other approaches like direct mail,without much success. Last year I decided to try marketing our LestroBlastsprayers in Citrograph. I had several new potential customers seek me out atthe World Ag Expo specifically because they had seen my ad in there. Citrusgrowers read Citrograph and I now advertise in every issue!”Contact us today to be included in future issues of CitrographSandy Creighton, Sales Manager • Phone: 559-201-9225E-mail: screighton@farmprogress.comrepresentatives from Sunkist, SyngentaCrop Protection, and Decco Postharvestin the commercial packinghousestudies, and thank the commercialpackinghouses in California for theircooperation in these studies.Additional readingEckert, J.W., and I.L. Eaks 1989.Postharvest disorders and diseases ofcitrus fruits. In The Citrus Industry. VolumeV. W. Reuther, E.C. Calavan, andG.E. Carman (eds.). Oakland: Universityof California Division of Agricultureand Natural Resources, 179-260.Kanetis, L., H. Förster, and J. E.Adaskaveg. 2007. Comparative efficacyof the new postharvest fungicidesazoxystrobin, fludioxonil, and pyrimethanilfor managing citrus green mold.Plant Disease 91:1502-1511.Kanetis, L., H. Förster, and J.E.Adaskaveg. 2008. Optimizing efficacy ofnew postharvest fungicides and evaluationof sanitizing agents for managingcitrus green mold. Plant Disease 92:261-269.Kanetis, L., H. Förster, and J. E.Adaskaveg. 2010. Determination of naturalresistance frequencies in Penicilliumdigitatum using a new air-samplingmethod and characterization of fludioxonil-and pyrimethanil-resistant isolates.Phytopathology 100:738-746.Klotz, L.J. 1978. Fungal, bacterial,and nonparasitic diseases and injuriesoriginating in the seedbed, nursery, andorchard. Pages 1-66 in: The Citrus Industry.Volume IV. W. Reuther, E.C. Calavan,and G.E. Carman (eds.). Oakland:University of California Division of Agricultureand Natural Resources.McKay, A. H., H. Förster, and J. E.Adaskaveg, 2012a. Efficacy and applicationstrategies for propiconazole as anew postharvest fungicide for managingsour rot and green mold of citrus fruit.Plant Disease 96:235-242.McKay, A. H., Förster, H., and J. E.Adaskaveg. 2012b. Toxicity of selectedfungicides to the postharvest pathogensGalactomyces citri-aurantii, G. geotrichum,and Penicillium digitatum andresistance potential to propiconazole.Plant Disease 96:87-96.Timmer, L.W., S.M. Garnsey, andJ.H. Graham (Eds.). 2000. Compendiumof Citrus Diseases. The American PhytopathologicalSociety Press. St. Paul,MN: 128 pp.Dr. J. E. Adaskaveg is Professor andH. Förster is Project Scientist, Departmentof Plant Pathology and Microbiology,University of California Riverside.CRB research project referencenumber 5400-103. l58 Citrograph May/June 2013

Citrus RootsPreserving Citrus Heritage FoundationIn this year’s January/February issue,we referred to the heritage behind theSunkist trademark as really being thebedrock supporting that value withinthe trade name. Very recently, I receivedthe annual report from Reliance Steel &Aluminum Co. The theme of the reportwas “Our history tells the story of ourfuture.” That says it all. The Californiapackers of citrus would add value totheir name if they rooted it to theirheritage. – Richard BarkerBuy our books, crate labels, make a cash contribution...Or give to Citrus Roots Foundation yourcrate labels, books, citrus memorabilia ...you willsave FED and CA taxes to the full extent allowed.Our website is a reference centerwww.citrusroots.comOur “Mission” is to elevate the awarenessof California citrus heritage throughpublications, education, and artistic work.We are proud of our accomplishments as a volunteerorganization, which means each donated dollar worksfor you at 100% [for we have no salaries, wages, rent,etc.]. All donations are tax deductible for income taxpurposes to the full extent allowed by law.Citrus Roots – Preserving CitrusHeritage FoundationP.O. Box 4038, Balboa, CA 92661 USA501(c)(3) EIN 43-2102497The views of the writer may not be the same as this foundation.The Building Boomof 1925-26 caused arelinquishment ofcitrus acreageRichard H. BarkerReal estate or building cycles occur at intervals ofbetween 18 to 20 years, as we discussed when we examinedthe Boom of 1887. The Bungalow Boom wasaround 1906, and the Boom of 1925-26 began to strengthenin 1921. It is the Boom of 1925-26 which we will presently address,along with how it affected the California citrus industry.The real estate bubble on the East Coast began around1921 and deflated around 1926. The housing prices commencedto turn down in 1926 and led to a rise in foreclosures.In the Midwest, heavy mortgages were placed duringWW I in expectation of continued high prices on farm commodities,though the postwar collapse of agricultural goodscaused widespread foreclosures. On the West Coast, residentialproperty rose steadily, though when the stock marketcrashed in 1929, values fell and foreclosures on residentialproperty peaked in 1933-34 and did not recover until WW II.We are very fortunate to have as our source the workingpapers of the legendary Harold J. Ryan, Commissioner ofHorticulture for Los Angeles County. (He held this positionfor decades.) This study was dated August 12, 1927, andthe manuscript was originally written for “Citrus Leaves,” amonthly paper devoted to the citrus industry and cooperativeactivities of the Pacific Coast.Mr. Ryan commenced with an explanation of the aggregationof the County of Los Angeles citrus in 1927 within excess of 50,000 bearing acres (90%) and the remaining10% mainly in young Valencias. The breakdown was bearingValencias totaling 22,809 acres and navels about 30% less,or 16,359 acres; lemons were about half of the Valencia totalor 11,898, and seedlings and grapefruit accounted for only1,234 acres.As to this 1927 study, Mr. Ryan chose to start his descriptionof the Los Angeles County citrus growing region with asolid block of about 30,000 acres beginning north of Puente60 Citrograph May/June 2013

at Baldwin Park extending northeasterly to Azusa and theneast along the foot of the San Gabriel Range 14 miles to thecounty line. He reported that through this area there washardly a ten-acre parcel of level land that was not planted tocitrus except where towns had risen.Between Pomona and Puente along Valley Boulevardand in the North Whittier Heights district there were 3,600acres, while south of the hills was a 10,000-acres block in theWhittier, Rivera, Downey district. This area had scatteredplantings of walnuts.The balance of the county citrus plantings were scatteredfrom Monrovia and Pasadena through La Canada toSan Fernando, Owensmouth, and Chatsworth.Practically all of the 6,000 acres lying in the Alhambra,Glendale, Sierra Madre, Monrovia quadrangle in 1927 werethreatened with an early extinction by subdivision.This completes the census by section of the county except,as Ryan stated, there were a few spots between BeverlyHills and Santa Monica that totaled 305 acres, and thisarea was soon to be subdivided the way of the old groves ofMay/June 2013 Citrograph 61

Photo album: PasadenaNow Orange GroveBoulevard takes on anew meaning…Pasadena 1910.Circa 1923. Arroyo Seco Bridge, Pasadena.Pasadena with developed orchards.Pasadena 1886.Pasadena 1882.Pasadena Orange Growers Association 1894.62 Citrograph May/June 2013

Pasadena, Altadena, and Colegrove (the Hollywood area).The writer thought it would help the reader to understandthe vast area of Los Angeles County which had originallybeen under citrus cultivation.Now, let us look at the table “Citrus Taken Out By Subdivision,etc.” Mr. Ryan wrote, “The most noticeable transformationwas found in the triangular area of the countybetween Glendale (including Pasadena), Alhambra andMonrovia. In the process of turning fruit trees to firewood ordoor-yard ornamentals, retired California ranchers sold over3,862 acres of citrus land for retired Iowa farmers to buildhouses upon.”To look at it another way, out of the 19 citrus bearingcommunities within the county, the aforementioned four cit-Photo album: HollywoodHollywood 1905.Hollywood 1905, Immaculate Heart High School (later college).Photo album: San Gabriel Valley1940 aerial of Azusa, Covina and Gendora looking to Mt. Baldy.May/June 2013 Citrograph 63

Volume I of IIIIncluding a fold outtime line chart ofby Marie A. Boyd and Richard H. BarkerVolume III of III$ 15 00Average of total packed boxes shipped brought $2.84 per box for Pasadena Orange Growers Assn. in 1918-1919.ies represented 53 percent of all the acreage sold over thefive- year period. One must remember that the buildingboom continued at a slower pace until 1929. That was thecenter of activity regarding the Boom of 1925-26.The 1930 population diagram by J. J. Jessup illustrates,at a glance, that the houses had to be built, and the populationfollowed the construction. As you can see, the populationexplosion was more pronounced in Burbank, Compton,Glendale, Pasadena, San Bernardino, San Fernando, SouthPasadena, and Whittier.Today, most of the population of California have fewclues as to citrus heritage. The footprint of the Californiacitrus industry has been left to vanish with few exceptions.Street names harken back to citrus connections. Water rightsare lasting legacies, though few students are exposed to thissubject. Citrus brand labels give some evidence of the past,though the labels of most of the brands of “old” SouthernCalifornia packers are very rare, and only the very few “serious”collectors recognize the name or brand.This is one reason we went to the trouble of dusting offthis old manuscript, so that the reader could again be familiarizedwith citrus birthrights -- to return, in a sense, to theformer place, to revert! To strike the anvil one more time.The citrus industry was on the “cutting edge” when ithad its first ad in 1908, the first saturated marketing campaign,the flatware promotional, etc., but for some reason themomentum was allowed to slow and disappear. The samecan be said about emphasizing the subject of “health” andCitrus Roots Series...Citrus RootsPreserving Citrus Heritage FoundationKeeping citrus heritage alive in the minds of those living in California through publications, educational exhibits and artistic works64 Citrograph May/June 2013GIFT IDEAS!!Citrus Roots...Our Legacy - Volume IVCitrus Powered the Economy of Orange Countyfor over a half century Induced by a “Romance”All donations are tax deductible for income taxpurposes to the full extent allowed by law.For ordering informationvisit our websitewww.citrusroots.comSelling the GOLDHistory ofSunkist ® and Pure Gold ®CITRUS ROOTS . . . OUR LEGACYBy: Rahno Mabel MacCurdy, V.A. Lockabey and others...compiled and edited by R.H. BarkerCitrus Roots...Our Legacy - Volume ISelling the Gold - History of Sunkist®and Pure Gold®Citrus Roots...Our Legacy - Volume IICitriculture to Citrus CultureCitrus Roots...Our Legacy - Volume IIIOur Legacy...Baldy View Entrepreneurs- 25 men & women who left a legacyOur Legacy:Baldy ViewENTREPRENEURSAmerican Business Cycles from 1810 to 1978vs. the Life Span of Twenty-Five EntrepreneursCITRUS ROOTS ... OUR LEGACY(Fed. Tax ID # 43-2102497)

also adding the “citrus gold rush” to the school curriculumrelative to California’s colonization. The citrus dollars builtcommunities! The jobs associated or linked to citrus carrieda heavy weight regarding the total labor sector.During the 1920s and 1930s, California citrus revenueranked second to the oil industry. The citrus industry hadits distinction, notability and muscle, but failed to preserveand give it an everlasting inheritance. Citrus heritage is thebedrock, or “store of value” to a citrus trade name. Let thaterode and per capita consumption of citrus goes the samedirection as the pull of gravity. (This is a lesson to the presentcitrus growing regions in California.)Richard H. Barker is the founder and president of theCitrus Roots-Preserving Citrus Heritage Foundation. For anumber of years, he has been leading a drive to bring abouta higher awareness of the role citrus played in developingCalifornia. Dick is a retired investment banker and wasa third generation Sunkist grower. He has published fourvolumes on citrus heritage.Photos and other material courtesy of: The Barker Collection;Huntington Library, San Marino, CA; County of LosAngeles Agricultural Commissioner/Weights and Measures;Sherman Library and Gardens, Corona del Mar. lCitrus Roots-Preserving Citrus Heritage Foundationneeds your help. Specifically, we need photos of packinghouses.In the immediate future, on our Foundation’s websiteyou will have at your disposal a listing of the more than2,000 packinghouses (no, that’s not a typo) that have beenin operation at one time or another over the history of theCalifornia citrus industry. Visit www.citrusroots.com.PEARSON REALTY Farm Sales Specialists for California’s Central Valley1.44± acs Exeter Commercial Building.................................................$250,0001.98± acs Cold Storage Facility, Orange Cove (Sale Pending)................$385,0002.62± acs Exeter Cold Storage Facility, High Quality..........................$1,975,0004.2± acs Exeter/Farmersville Area Homesite.........................................$149,0006.48± acs Turnkey Citrus Packing/Cold Storage.................................$1,950,0006.48± acs Porterville Area Ranchette & Homes (SOLD).........................$195,0008.4± acs Oak Lined Home Site (SOLD)..................................................$325,0009.72± acs Cutler Area Cold Storage/Offices.......................................$2,399,00010± acs Strathmore Area Citrus (In Escrow)..........................................$120,00014.92± acs Lemon Cove Navels & Home Site (In Escrow).....................$285,00015.98± ac Lindsay Development Potential............................................$280,00020± acs Easton Cherry Ranch (SOLD)...................................................$280,00020± acs Porterville Ranch & Home (In Escrow).....................................$405,00020± acs Lindsay-Strathmore Area Citrus & Residence..........................$595,00020± acs Orange Cove Navels & Home..................................................$450,00020.18± acs Sanger Citrus/Residence....................................................$875,00025.96± acs Lindsay Area Open Land (SOLD).........................................$395,00035.4± acs Orosi Area Citrus (SOLD)......................................................$415,00037.40± acs Cutler Area Citrus...............................................................$828,00040± acs Valencia Oranges & Open........................................................$360,00040.16± acs Tulare County Olives (In Escrow).........................................$595,00057.24± acs Navel Oranges...................................................................$745,00059.98± acs American Ave Citrus & Olives (In Escrow)...........................$900,00080.18± acs Navel Oranges & Olives North of Reedley...........................$965,00090.30± acs Cutler Area Navels..........................................................$1,080,00094.81± acs Porterville Area Walnuts & Open (SOLD)..........................$1,500,00095.22± acs Pistachios & Citrus (SOLD)..............................................$1,650,000127.33± acs Orange Cove Citrus Ranch with Custom Home..............$2,500,000158.41± acs Orosi Organic Citrus......................................................$1,425,000171.08± acs Stone Corral Area Open (In Escrow)...............................$1,625,260236.4± acs Citrus Ranch (In Escrow).................................................$3,000,000320± acs South County Citrus Ranch.................................................$5,120,000498± acs Antelope Valley Ranch........................................................$3,200,000604.37± acs Hills Valley Ranch..........................................................$1,725,000For Brochure Contact: Roy Pennebaker #0845764 (559)737-0084 orMatt McEwen #01246750 (559)280-0015 • www.citrusboys.comMay/June 2013 Citrograph 65

Celebrating CitrusAnne WarringSummer is the perfect time for experimentingin the kitchen, and we havejust the thing.While in Spain for the InternationalCitrus Congress last fall, a group of Californianswent on a pre-Congress tour.They traveled south from the conferenceheadquarters in Valencia to the city ofMurcia and then on to Andalucía.Of course, their reason for the touringwas to visit orchards, nurseries, and processingplants, but there were side attractionseverywhere, and Murcia just happensto have some of the very best food in allof Spain.Among the delicious discoveries thatthe Citrus Research Board delegation justcould not stop talking about when theywere back in California was a delightfuland most unusual dessert called “Paparajotes”,or Sweet Battered Lemon Leaves.Something fun and differentMaryLou Polek at a restaurant inMurcia, Spain.(You don’t actually eat the leaf, just thepastry.)It’s a delicacy that Murcia is knownfor, and it’s what CRB’s Dr. MaryLouPolek was about to enjoy when she wascaught by Ted Batkin’s candid camera.You can easily try this at home becausethere are recipes and instructionson a number of websites. Basically, we’retalking about coating fresh lemon leaves --preferably younger leaves -- with a battermade of milk, water, flour, eggs and sugar(sometimes with yeast and usually withlemon zest and cinnamon included), panfrying them in olive oil, letting them drainon a paper towel, and finally dusting themwith sugar and cinnamon.The version that MaryLou has in-handis topped with a drizzle of chocolate, andseveral of the write-ups online suggestserving Paparajotes with ice cream or addingsome crème brulee.To get started, visit:• www.worldsofflavorspain.com• www.regmurcia.com• www.arecetas.com• www.spain.info/enYou can even find how-to videos onYouTube.Something forthe grillCaribbean Salsa(for fish and chicken)• Grated peel of 1/2 lemon• Juice of 1 lemon (3 tbsp)• 1 med avocado, peeled, pitted,finely chopped• 1 med papaya or mango, peeled,seeded, finely chopped• 1/3 cup diced purple onion• 1 tbsp honey• 1/2 to 1 small jalapeno pepper,minced (optional)• Generous dash each cinnamonand allspiceIn bowl, sprinkle lemon peel and juice overavocado. Add remaining ingredients andgently stir. Serve at room temperature orcover and chill 1 to 2 hours. Serve withgrilled or baked halibut or swordfishsteaks, or chicken. Makes about 3 cups.You’d be amazed at the results of a Web search using the keywords “lemonmarinades.” Just out of curiosity we did some exploring, and on MarthaStewart’s website alone the number that comes up is 189!In the print world, while looking through the archives of Citrograph, we cameacross these Zesty Marinades in the July 1994 edition, in the “Citricreations” sectioncontributed by Sunkist’s consumer services department. (The step-by-step instructionsfor grilling have been left out here because the information was verybasic.) In that same section, which was all about outdoor cooking, there was also arecipe for a lemony salsa to go with fish and chicken.Lemon, Mustard ‘nThyme Marinade(for pork and lamb)• Grated peel of 1/2 lemon• Juice of 1 lemon (3 tbsp)• 2 tbsp olive oil• 1/2 tbsp grated shallots or purpleonion• 2 tsp Dijon mustard• 1 tsp finely chopped fresh thymeleaves• 1/4 tsp garlic salt• Fresh grated pepper to tasteTo make the marinade, combine allingredients.Citrus and RosemaryMarinade(for fish and chicken)• 2 tbsp vegetable oil• 2 tsp finely chopped fresh rosemaryleaves• 1 med clove garlic, minced• Grated peel and juice of 1/2 lemon• Juice of 1 orange (1/3 cup)• 1/8 tsp white pepperTo make marinade, in small non-stick skillet,heat oil; add rosemary, garlic and lemonpeel. Cook over low heat 1 to 2 minutes toinfuse oil with flavors. Remove from heat;add lemon and orange juices and pepper.66 Citrograph May/June 2013

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