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Gaagal Wanggaan National Park(Warrell Creek Peninsula)WEED MANAGEMENT STRATEGY

About this strategy ………..This Strategy was funded by Caring for our Country as a part of NambuccaValley Landcare and Nymabaga Goori Green Team Protection Proposal Thestrategy document draws upon publically available resource material for thecontrol of weeds, on advice from key weed control and land managementprofessionals and from the experience of the author controlling these weedsin similar landscapes.The document describes a sequence of actions which will effectively andefficiently remove the weeds from Gaagal Wanggaan National Park (WarrellCreek peninsula). The strategy balances the need for weed control with theneed to to minimise the risk of off-target effects to the environment, sites ofcultural significance and the local community.Maps contained within the document have been produced by Green EarthWorks P/L from information supplied by the author.Stuart JohnsonFebruary 2010.Caring for our Country Gaagal Wanggaan Weed Management Strategy 2

Gaagal Wanggaan - Weed Management StrategyContentsAbout Gaagal Wanggaan …..…………………………………………………. 4Principles of Weed Control ……………………………………………………. 7The three phases of weed control ……………………………………………. 7Primary treatment phase ………………………………………………………. 7Secondary or follow up treatment phase …………………………………….. 8Maintenance treatment phase ………………………………………………… 8Stages of weed control ………………………………………………………… 8Overview of weed control techniques ………………………………………… 10The neighbours …………………………………………………………………. 10Choice of herbicides ……………………………………………………………...11Vegetation of Gaagal Wanggaan ………… …………………………………… 13Foredune vegetation …………………………………………………………… 17Littoral rainforest ………………………………………………………………… 23Estuarine wetlands ……………………………………………………………… 26Dry sclerophyll/ tall dry heath …………………………………………………. 29Threatened species …………………………………………………………….. 33Essential references ……………………………………………………………. 35Appendix A - Plant Species Recorded for Gaagal Wanggaan ……. ……… 36Appendix B - information on herbicides recommended for use ……………. 40MapsMap sheet 1:Gaagal Wanggan management zonesZone 1 …………………………………………………… 14Map sheet 2: Zone 2Zone 3 …………………………………………………… 15Map sheet 3: Zone 4Zone 5 …………………………………………………… 16Schedule of works ……………………………………………………………… 34Caring for our Country Gaagal Wanggaan Weed Management Strategy 3

To summarise, the main body of the peninsula is less than six thousand yearsold, the high front dune along Forsters Beach is about two and a halfthousand years old.This very simple landscape is complicated only by the meandering nature ofWarrell Creek along the western flank of the peninsula. The creek wandersfrom side to side as all running water is compelled to do, each meander bendslowly eroding its way downstream as it wears away the downstream end ofeach bend, and depositing the material eroded from further upstream againstthe inside of each bend. The low lying swampy sections of Gaagal Wanggaanwhich are seen against the right bank of the creek, are old sections ofchannel, now abandoned by the process described above, and now slowlyaccumulating silt from floods and organic matter from the sedge vegetation.Aboriginal people, the Gumbaynggir have used the Gaagal Wanggaan quiteliterally from the time of its creation. Estuarine areas generally, on theinterphase of salt and freshwater ecosystems are well known for theirabundant food resources. Not surprisingly there are a number of sites on thepeninsula where past use of the land by Aboriginal people is evident. Thesesites are regarded as culturally significant. Aboriginal people are,understandably, often reluctant to formally disclose the exact location of suchareas but they are well known to Elders and Knowledge Holders. The culturalsignificance of these areas warrants special care when considering anylandscape management.The use of the peninsula by Europeans following their arrival has been moreprosaic. Of little use for timber production or pasture development (prettymuch what European settlers did elsewhere at that time) the peninsula wasopportunistically grazed in its unimproved state. Fortunately it remained inpublic ownership as Crown Land. Today little has changed except the cattleare long gone. A site has been made at the Scotts Head end for a sewagetreatment plant operated by the Shire Council serviced by an all weather dirtroad. Where this formed road stops a 4WD access track continues its waynorth wandering between the trees to a little more than half the length of thepeninsula giving boatless fishermen access to lower sections of WarrellCreek. As always provision of vehicle access results in the illegal dumping ofrubbish including garden waste, a practice which remains a source of newweeds. 4WD vehicles also have access to the full length of Forsters Beachwith drivers asked to observe a seasonal closure of the northern end duringthe breeding season of the Little Tern colony.No information is available on the use of fire on the peninsula by theAboriginal people but it is highly likely. The same goes for the early Europeanarrivals. In any case, fire has obviously been a part of the history of thepeninsula, its effects being clearly evident in the pattern of vegetation. Theblackened trunks of trees tell of recent fires, the predominance of fire tolerantplant species tells of a much longer fire history.Knowing this history helps explain three important aspects of the ecology ofthe peninsula. Firstly the peninsula is made almost entirely from beach sand,Caring for our Country Gaagal Wanggaan Weed Management Strategy 5

a growing medium with very serious limitations for plants, particularly theirpoor nutrient status and poor water holding capacity. In response thevegetation is of low diversity, given that it can only be colonised by plants thatcan cope with these growing conditions.Weeds, being plants, are also subject to these constraints. Relativelyspeaking Gaagal Wanggaan exhibits low weed diversity and density, and thepattern of weed occurrence is directly influenced by landscape.Secondly the pattern of vegetation distribution across the peninsula is a directreflection of the landscape, each landscape component (foredune, old creekchannel and main dune body) has its own characteristic vegetation. This isimportant because a weed management strategy must consider the pattern ofweed occurrence in order to set priorities.Lastly, fire has had an important role in shaping the pattern of plantdistribution (including weeds) across the peninsula particularly that of littoralrainforest, a priority for management.Recognition of these factors is the first step in tailoring a weed control strategythat is both effective and efficient.Caring for our Country Gaagal Wanggaan Weed Management Strategy 6

Principles of weed controlThere is an enormous amount of reference material documenting theintimacies of weed management and bush regeneration, discussions onvarious techniques, scientific analyses, case studies, testimonials etc and thereader is directed to the reference list at the end of this document for the mostrelevant information. This strategy draws upon information from these sourcesto make the best use of the advantages offered by each particular technique.For the purposes of this plan for Gaagal Wanggaan, the following weedmanagement principles are relevant and should be applied to any decisionmaking.• Weed control should aim to minimise damage to the natural ecosystem• Strategy should aim to make maximum use of natural regeneration• Weed control strategy should be prioritised• Weed control should be staged, based on priorities• Pace of weed control based upon the capacity for follow up• Maintenance weeding is the minimum weed control work required tomanage weeds. This strategy aims to control weeds to maintenancelevel.The weed control strategy is designed, generally speaking (and not includingthe high priority sites) to progress from south to north along the peninsula.The three phases of weed controlWeed control is never as simple as a single treatment, regardless of howthorough it might be (although thoroughness is a key part of any successfulcontrol programme). A weed removal strategy must consider control over aperiod of time, largely determined by the ecology of the weed species inquestion.A population of weeds on a particular area (picture a single clump of weedssuch as Bitou or Lantana or a mixture of both), will respond in certainpredictable ways once control measures are commenced. This in turn mayinfluence further control measures, in order that they continue to be aseffective and efficient as possible. The phases of weed control refer to thepredictable changes in a weed population, regardless of species, during acontrol programme.Primary treatment phaseA population of weeds exists as a collection of mature seed producingspecimens, less mature specimens not yet producing seeds and smallseedlings. Whilst it might be tempting to think of the job at hand in terms ofsimply removing this standing crop, this work constitutes only the first of threephases of the weed control. This document refers to this first phase, removalof the standing weed plants, as the primary treatment.Caring for our Country Gaagal Wanggaan Weed Management Strategy 7

The time required for successful primary treatment is governed by thedifficulty in killing the individual plants, the density of the standing crop and thearea covered.Secondary or follow up treatment phaseIn addition to the weed plants present on site a weed population also includesany viable seeds in the soil, the soil seed bank. Soil stored seeds may beclose to the standing plants or, if the plant has evolved an effective seeddispersal mechanism such an edible fruit, may have been carried aconsiderable distance from the source. The greater the number of seeds inthe soil seed bank, and the longer they can remain viable, the greater theproportion of secondary treatment in the weed control programme.Bitou Bush in particular may have a spectacular soil seed bank with someresearchers reporting seed densities under a standing Bitou canopy ofbetween 2000-3000 seeds per square metre (Weiss, 1984). More recentcounts, done since the establishment of bio-control agents which prey directlyon the seeds, record soil seed densities of 570 seeds/m 2 with only 23%viability, still an impressive 130 viable seeds/m 2 . Interestingly this figuredropped to less than 2 seeds/m 2 20 metres from the canopy confirming thatthe bulk of the seed bank lies directly underneath the standing crop of Bitou.Seed longevity is the other factor influencing the required duration ofsecondary treatment and again it is specific to the ecology of each individualweed species. To use Bitou Bush as the example again, the seed longevity isthought to be at least five years. It may be possible to deliberately manipulatethe soil seed bank to our advantage. Bitou seeds are stimulated to germinateby increased light levels produced by aerial spraying and by the samemechanism, as well as the chemical products released, following a fire.Because a seed can germinate only once, a mass germination means also amass reduction in the number of viable seeds remaining in the soil.The time required for successful secondary treatment is governed by the sizeof the soil seed bank and seed longevity.Maintenance treatment phaseOnce the standing plants have been removed and the soil seed bank depletednew weed plants may arrive on site, carried by some seed dispersalmechanism such as animals (primarily birds), wind or floods. Control of thesenew arrivals, generally by regular hand pulling of small seedlings representsthe maintenance treatment phase and will need to continue while ever matureplants remain within dispersal distance of the site. As this will be out of thecontrol of the managers of Gaagal Wanggaan, the maintenance phase will bea long term, if not a perpetual one.The key to an effective maintenance treatment phase is to remove new plantsbefore they have an opportunity to set seed.Caring for our Country Gaagal Wanggaan Weed Management Strategy 8

The weed management strategy described here prescribes a sequence ofweed control which is designed to reduce the populations of weed speciespresent to one of maintenance weeding. It describes the number andfrequency of treatments required to deliver effective control and is sensitive tothe ecology of the weed species present. This treatment schedule is basedupon the minimum effort required to be effective. Should extra resources beapplied then this would be advantageous though not necessarily significant inreducing the time required to arrive at the maintenance treatment phase.The period of time required for successful maintenance is related to control ofweeds on neighbouring land which is generally out of our control and rarelythe subject of concurrent control. For this reason the maintenance phase ispractically ongoing.Stages of weed controlStaging refers to the way in which we apply the three phases of control to ourwhole project area. An area such as Gaagal Wanggaan is far too large to beable to treat the whole area at once. We must work in stages if we are tocover the whole area and the way in which the control is staged must aim tobe as effective and efficient as possible. In order to achieve this we need toprioritise the work required.In broad terms the basic stages of this plan are:1. to identify and commence work on areas of greatest significance. Inthis case they are the pockets of littoral rainforest (an endangeredecological community) and sites of high cultural significance to theTraditional Owners. These sites occupy only modest areas andeffective control can be achieved relatively rapidly.2. work from areas of good condition (in other words low weed density)first. The areas covered by estuarine wetlands have few weeds at lowdensities and are given the next priority. The areas covered in drysclerophyll vegetation are generally in good condition Because thearea covered by dry sclerophyll is very large, it will be broken up intozones and each zone will be worked on until the maintenance phase isachieved before moving on to the next zone. There are five zones, andwork will commence on the southernmost zone and move north.3. leave areas of higher weed density until last. The area of highest weeddensity is the foredune of Forsters Beach. Because of the applicabilityof aerial spraying which is very cost effective, and the good condition ofthe great majority of the peninsula area, the control of (primarily BitouBush) on the foredune is scheduled concurrently with the other works.The schedule for weed control over the project area is given for eachvegetation type as well as for the project as a whole. The speed at whichweed control might be delivered is principally one of available manpowerwhich in turn is a product of available funding. Whilst the reaction of weeds toa control programme is reasonably predictable the reaction of funding sourcesis less so.Caring for our Country Gaagal Wanggaan Weed Management Strategy 9

The following control strategy and the accompanying schedule are predicatedon the availability (ie affordability) of the local Green Team of at least sixmembers (for most of the time). At this level of resourcing, control of weedsover the whole peninsula to maintenance level should be possible withinseventeen years. Should funding dry up then it is virtually inevitable that theresult will be a prolongation of the time frame required to achieve themaintenance phase.Overview of weed control techniquesThe following terminology is used to describe weed control techniques withinthis document.Hand weeding techniques• includes physical removal of weed specimens by manual ormechanical means• physical removal of above-ground part of weed specimens andapplication of herbicide to the stump (ie cut-and-paint)• exposure of conductive tissue and application of herbicide (ie scrapeand paint) on standing weed specimens• foliar application of herbicide by backpack spraying equipmentHigh volume spraying of herbicide• use of pump driven herbicide application equipment such as QuiksprayunitAerial application of herbicide• use of aircraft for foliar application of herbicideBio-control• use of natural plant predators for weed suppression and control. Sixagents have been successfully established for Bitou Bush control.Seventeen agents have been successfully established to controlLantana. Whilst these bio-controls are demonstrably affecting thesetwo weed species none has had a significant effect on extent or densityof either weed.The neighbours …….Many weeds are problematic because they have effective dispersalmechanisms which allow them to move considerably further than if their seedsimply fell from the parent plant. Flying animals such as birds and bats, floodsand wind are the most common long distance dispersers of weed seeds inthis locality. There are some very serious weeds known from nearby areaswithin flying (blowing or swirling) distance of the peninsula.A further vector of weed dispersal is those residents of Scotts Head whoseem to have no issue with dumping garden waste alongside the track whenCaring for our Country Gaagal Wanggaan Weed Management Strategy 10

no one is looking. A collection of weeds delivered thus can be found adjacentto the sewage treatment plant.Of particular concern are the following weed species:Common Botanical known from … weed of… spread by …name nameGlory Lily Gloriosa Scotts Head dunes birdssuperbaAsparagus Genus Scotts head, Nambucca all habitat types birds‘Ferns’Protasparagus Heads, GummaOchna Ochna serrulata Scotts Head, Gumma, littoral rainforest birdsNambucca HeadsBroad-leaved Schinus Scotts Head, Nambucca all habitat typesPepper Tree terebinthifolius HeadsCamphor Laurel Cinnamomum Scotts head, Gumma, littoral rainforest, dry birdscamphora Nambucca Heads sclerophyll, wetlandmarginsGiant ParramattaGrassSporobolusfertilisNambucca Shire roadsides vehicles,animalsSpiny Burr Grass Cenchrus spp. Scotts Head dunes animalsIt is vital that weed control workers, who are the people with greatest contactwith the landscape, are familiar with these weed species and that anysightings be reported and acted upon immediately. Glory Lily is of suchconcern that if it is located in the dunes, particularly following an aerial spray,its treatment must become the highest priority. Advice on control methods forGlory Lily will be required from the Mid North Coast Weeds AdvisoryCommittee or the Shire Weeds Inspector if this happens.Choice of herbicideMeaningful control of weeds on Gaagal Wanggaan is not possible without theuse of herbicides. The strategy described here uses herbicides in a strategicfashion in order that:• total volume of herbicide applied is minimised• maximise use of non-herbicide techniques• risk of off-target damage is minimised• choice of herbicide type to minimise any risks to community andenvironment• herbicide use will be as per directions on labelThe use of herbicides will be restricted to the use of glyphosate andMetsulfuron methyl as described below. A description of the formulation andmode of action of these two chemicals is presented at the end of thisdocument.application herbicide rateHand removaltechniques such as cutglyphosateneatCaring for our Country Gaagal Wanggaan Weed Management Strategy 11

and-paint (all weedspecies)Aerial spraying of BitouBushHigh volume andbackpack spraying ofBitou, Groundsel,grassesHigh volume andbackpack spraying ofLantana and Sennaglyphosate as ipa 360g/l 2 litres per hectareglyphosate as ipa 360g/l 1 part glyphosate: 100parts waterglyphosate as ipa 360g/land Metsulfuron methyl600g/kg1 part glyphosate: 100parts water plus 10gMetsulfuron methyl :100 litres mixThe use of herbicides on public land is controlled by the Pesticides Act 1999,specifically the Pesticides Regulation 1995. This Regulation is being rewrittenand project managers have a responsibility under the Regulation to ensurethat they are operating consistent with the provisions of this legislation.Caring for our Country Gaagal Wanggaan Weed Management Strategy 12

Vegetation and weeds of Gaagal WanggaanThe flora of Gaagal Wanggaan is relatively simple. There are a limitednumber of vegetation types, none of which are particularly species diverse.There is generally a strong link between vegetation type and landform.For the purposes of creating some context for a considering weedmanagement on the peninsula the vegetation can be described in terms of thefollowing categories:• vegetation of the Forsters Beach foredune• littoral rainforest• estuarine wetlands• dry sclerophyll forest – tall dry heathThe accompanying maps presented on the following pages show thedistribution of each of these vegetation types across the peninsula.In common with the native vegetation weed diversity is low across thepeninsula. To give some perspective, Bitou Bush and Lantana represent 80%and 15% respectively of the plants which make up the standing weed crop.Weed density is also low with the only exception being the Bitou Bushinfestation along the Forsters Beach foredune. This is cause for optimismbecause control of these weeds, ie removal to maintenance level, is physicallypossible and within achievable levels of funding.Because the pattern of weed occurrence is strongly influenced by vegetationtype the weed control recommended in this strategy is broken down intocontrol by vegetation type. Further, this work is prioritised according to:• ecological significance of the vegetation type and culturally significantsites• work from areas of low weed density first• staged control over large areasCaring for our Country Gaagal Wanggaan Weed Management Strategy 13

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Foredune vegetationThe frontal dune which faces the beach is a harsh environment for plants,made up of virtually pure sand blown up from the beach and exposed tofrequent strong, salt laden winds. A specific suite of highly specialised plantsoccupies the beachfront dune which as described previously runs the lengthof Forsters Beach and is about 50 metres wide (measured from the line of thehighest tides) at its widest point.Photo 1. eastern face of foreduneThe fact that there is a dune here at all is a direct result of the plants. Strongwinds blow sand back from the beach, but the wind can only carry sand grainsonce it has reached a certain velocity. The plants tend to deflect the strongwind over the top of themselves with much reduced wind movement below thelevel of the canopy. Whilst the wind has sufficient energy to transport sandacross the beach, once sand grains drop between the plants on the dune facethe wind can no longer move them. Grain by grain they accumulate to formthe dunes we see today.In its natural state this vegetation, whilst species poor, would have completelycovered the dune, with each of the major species being more or less equallyrepresented in the mix. This vegetation type is typically short growing indeference to the regular strong wind, particularly on the most exposed face ofthe dune. Short growing grasses which require high light levels to do well, andCaring for our Country Gaagal Wanggaan Weed Management Strategy 17

which generally occur as ground covers under a much taller canopy in mostother vegetation types, made up a significant component of the canopy coveron the dune. The shade created by these plants would have reduced theeffects of the sun, keeping the sand cooler, reducing moisture loss throughevaporation (in other words the microclimate) and creating a source of organicmatter and nutrients in a very efficient process of nutrient cycling. Recreatingthis environment is an important consideration of any management.Native plants recorded for the foredune are listed in Appendix A.Weeds recorded for the foredune are listed below.Common name Botanical name occurrenceBitou BushChrysanthemoides monilifera ssp. commonrotundataLantana Lantana camara scatteredPennywort Hydrocotyle bonariensis scatteredThis is the vegetation type most affected by weeds on the peninsula,predominately by Bitou Bush. Bitou Bush has evolved to do very well in thisenvironment. Being a bird spread plant it has the ability to spread effectively,its taller growing habit and broader leaves conspiring to allow it to grow over,and shade out, the original sun-loving grasses. As a weak scrambler it canclimb into the canopies of the taller natives, depriving them of sunlight andgradually taking over the spaces they occupy in the canopy. The densershade cast by the leaves of the bitou bush are thought to reduce thegermination of native plants and, as if all this were not enough, the plant isknown to release chemicals known as allelopaths which further hinder thegrowth of native plants. As a result Bitou Bush is now the dominant plant onthe dunefront along Forsters Beach.The mechanics of Bitou control are discussed later, but in considering itsremoval, the most important consideration for management is the rapid reestablishmentof the native plant cover, to reinstate the appropriate canopyand microclimate and minimise the wind erosion of the dune material.Because such a large area is involved a staged approach, which only disturbsa discrete and manageable area at any one time is required. In the favour ofBitou control, there is a great deal known about the removal of Bitou andsubsequent restoration of the beachfront, and a list of reference material isgiven at the end of this document. Most significant is the development ofaerial spraying techniques which allow the removal of Bitou over a large areawhilst having minimal impact on native plants. Many of the native plantsinvolved are able to recolonise the dunefront rapidly once Bitou is removed.Foredune restoration sequenceAerial spraying is recommended for controlling Bitou Bush on the eastern faceand crest of the foredune as it is the only technique which can treat the largearea affected and enormous number of individual weed plants. At anapplication rate of 2litres/hectare (glyphosate) it is also the most conservativeCaring for our Country Gaagal Wanggaan Weed Management Strategy 18

technique in terms of herbicide output. A staged approach is necessarybecause whilst aerial spraying is very quick and cost effective the techniquesrequired for follow up are less so. Hence it is the capacity for follow up whichdetermines the rate of treatment.Photo 2. dense regeneration of Bitou Bush following primarytreatmentThe aerial application of glyphosate is effective for killing Bitou only. Releasedfrom the competition the remaining unaffected plants will begin to take overthe gaps left by the dead Bitou. Unfortunately Lantana is one of these plantsand it will need to be controlled separately, preferably just prior to, and duringthe period of aerial spraying. The low density of Lantana plants indicate handremoval techniques (such as backpack spraying) are most suitable, butshould any large patches be discovered then high volume spraying may benecessary.The aerial spray will require liaison with the existing aerial Bitou controlprogram in this locality and the best point of contact is the Mid North CoastWeeds Advisory Committee. In this way organisational efficiency of theoperation can be maximised, particularly the reduction of costs associatedwith ferrying (relocating) the machine.The timing of the spray should be late autumn to early winter, and conductedduring the hours following dawn when there is generally a gentle katabaticCaring for our Country Gaagal Wanggaan Weed Management Strategy 19

(offshore) breeze which will carry any drift away from the adjoining vegetation.One aerial spray per year is required.Aerial spraying represents the initial knockdown and follow up phases of Bitoucontrol on the foredune and should ideally be continued yearly until theremoval of standing plants and regrowth from seed stored in the soil. It isgenerally accepted that Bitou Bush seeds can remain viable under fieldconditions for up to five years. Whilst aerial spraying is the most cost effectiveway of treating weeds over large areas, including the predicable massgermination following the first treatment aerial spraying is recommended foronly three consecutive years. By limiting the period of aerial application in thisway we minimise any risk of cumulative damage to native plants. Elsewhereon the mid north coast two or three aerial sprays have reduced the Bitou soilseed bank such that ground control is possible for that point onward.A full checklist of aerial spraying preparations, and there are many, is given inthe ‘Best practice guidelines for the aerial spraying of bitou bush in New SouthWales’ available on the DECC website.The western face of the foredune is not suited to aerial spraying because ofthe proximity of tree canopies. Primarily this is because the canopies preventthe herbicide from reaching the Bitou Bush growing underneath so thetechnique is less effective. Secondly, whilst the work of Toth (see herbicidesensitivity lists in ‘Best practice guidelines for aerial spraying of Bitou Bush inNew South Wales’) indicates that the tree species present are resilient to lowlevels of herbicide exposure it is prudent to employ the precautionary principleand not subject them to unnecessary hardship.Accordingly it is recommended that the western face of the foredune besprayed from the ground, twice per year. High volume spraying is the onlypractical technique available for such a large area. Glyphosate is theherbicide of choice because any overspray has shorter persistence in the soil.This edge spraying is best done a month or so following the aerial spray sothat the aerially treated plants are most visible. The ground spraying will benecessary for the same three year period as the aerial programme.Following the three years of spraying the whole of the dune (ie the front, crestand western face) should be ready for the manual follow up control phase. Atthis time preparatory Lantana spraying should be commencing on the nextcontrol zone to the north.The exact nature of follow up control will not be known until the end of thespraying period, and will be influenced by many factors. However, by thispoint the Bitou population will have been reduced to seedlings germinatingfrom a depleted soil seed bank. Control from this point should be possiblemanually and without herbicide provided sufficient labour is available. At leastsix people will be needed (such as the Nyambaga Green Team) in asystematic ‘emu line’ fashion by hand pulling seedlings.Caring for our Country Gaagal Wanggaan Weed Management Strategy 20

The other work required preparatory and coincident to aerial spraying is therestoration of the soil seed bank of native plants. The key structural speciesfor canopy re-establishment are Coastal Wattle and the grass Beach Spinifex.Coastal Wattle is a common species on the mid north coast. Large quantitiesof seeds are produced in favourable seasons which ripen around Novembereach year. The seed has a long shelf life if handled properly (dried, cleanedwithout delay and refrigerated to prevent mould and insect attack) and canalso last for years in the soil as a seed bank. It is recommended that collectionof as much Coastal Wattle seed as resources permit occurs. It should bespread across active treatment areas and also into areas planned forsubsequent Bitou control, in order that a seed bank is re-established. Acaciaseed can be heat treated to crack the seed’s hard coat and bring forward thegermination, most easily by plunging the seeds into boiling water for severalminutes, rinsed under cold water and spread to dry. This is done to encouragea more rapid recolonisation. Rapid germination and delayed germination bothhave advantages in landscape scale restoration and only a fraction (say 30-40%) of seeds to be spread should be heat treated. The untreated seed willgerminate when nature dictates over a longer period. Spreading seed isideally done before or during a period of rainfall, the rain will help bury theseed away from animals which might eat them and provide soil moisture forthe seedlings.If sufficient quantities of seeds can be collected (you can never have toomuch) it might be cost effective to broadcast them from the helicopter at thetime of spraying. A helicopter mounted seed spreader has been used verysuccessfully in this way along beachfronts in the nearby Bellinger catchment.Beach Spinifex is easily re-established from seed provided it is fresh or bytransplanting runners. Seeds are generally ripening aroundNovember/December. When using seeds care must be taken to ensure theseeds are sufficiently ripe by picking them when they have turned from greento brown (or have dropped off the parent plant and been blown free, oftenconveniently collecting in large numbers against other plants or beach debris).Seed viability decreases rapidly with time especially if storage conditions arenot perfect. The globular seed heads may be broken up and planted, three orfour together at a depth of around 100mm. Runners are best transplanted inthe cooler months and into moist sand following rain. Runners must bepicked, kept moist and planted as quickly as possible. Only the ends of therunners with the growing tip will grow successfully.Re-establishment of these key structural species is the priority, but once thishas been addressed, and if further resources are available, seeds andpropagation material from the other dunefront species can also be used (seeplant list provided).When sourcing seed for landscape restoration, due regard needs to be givento the issue of seed provenance. Ideally seed of these species should besourced from as close as possible from the restoration site. Seed collectionCaring for our Country Gaagal Wanggaan Weed Management Strategy 21

for dunefront restoration should be confined to coastal areas within theHastings, Macleay and Nambucca catchment areas.Treatment schedule for the foredune (by zone)Primary treatmenttask frequency techniqueLantana control (wholedune profile)twice per year backpackspraying or handpullingaerial spraying of foredune once per year helicopter(east face & crest) BitouBushwestern face of foreduneBitoutwice per year high volumespray (Quikspray)seed collection andonce per year as describedspreadingmonitoring once per year as describedSecondarytreatmentremoval of Bitou Bush andLantana seedlingsseed collection andspreadingthree times per yearonce per yearhand removal(spraying ifnecessary)as describedmonitoring once per year As describedMaintenancetreatmentRemoval of Bitou Bushand Lantana seedlingstwice per yearhand pullingseed collection andonce per year as describedspreadingmonitoring once per year as describedCaring for our Country Gaagal Wanggaan Weed Management Strategy 22

Littoral rainforestLittoral rainforest is considered (by Floyd at least) as an expression ofsubtropical rainforest occurring on the drier areas along the coast. Whilst stilla rainforest and with a rainforest’s typical range of species it is nonethelessspecies poor as rainforests go. And the drier the site, and the greater theinfluence of other environmental factors, the less species will be present. OnGaagal Wanggaan the dryness of the site is a product of the low waterholding capacity of the sandy soils. It is a very significant limitation, and thelittoral rainforests on the peninsula exhibit a very low diversity of plantspecies.Whilst soil moisture determines the species composition of littoral rainforests,it is fire which in turn determines more than any other factor, their spatialextent. Most rainforest plants have little or no ability to survive fire.The effects of these two influences are clearly seen in the distribution andnature of littoral rainforest on Gaagal Wanggaan. It is of no surprise that thelittoral rainforest is restricted to small patches along the bank of Warrell Creekwhere it is physically separated from the main body of the peninsula by openwater or wet estuarine wetlands, and hence shielded from fires. This locationalong the creek bank also gives greatest access to groundwater and to whatscant alluvial soil development is present.Photo 3. littoral rainforestCaring for our Country Gaagal Wanggaan Weed Management Strategy 23

Isolated specimens of rainforest plant species, including some large trees canbe found growing on the lee of the foredune, out of the wind and with accessto a likely lens of freshwater stored within the dune itself. These plants do notexhibit any real canopy linkage or closure and do not constitute ‘rainforest’ perse but they do indicate suitable conditions for the establishment of a littoralrainforest in the absence of fire. Indeed scattered seedlings and specimens ofthe more pioneering and fire tolerant species (a very few littoral rainforestplants can survive from coppicing from below ground after fire) can be seenacross the whole of the peninsula.It is highly likely that fires are an anthropogenic feature of the peninsula, and itis further likely that the frequency and maybe intensity of fire increased afterEuropean settlement. The fact that there are large mature specimens ofrainforest trees (which obviously established safe from fires) but very fewseedlings around them (removed by more recent fires) raises the possibilitythat fire frequency, intensity or both have increased during the lifetime ofthese large trees. It seems probable that a thin band of littoral rainforestexisted along the lee of the front dune at the time of European settlement andthat this has deteriorated through a lack of recruitment to its present state.Native plant species recorded from littoral rainforest are listed at Appendix A.Weed species recorded for littoral rainforest are listed below:Lantana Lantana camara scatteredBitou bushChrysanthemoides monilifera ssp. scatteredrotundataFive-leaved Morning Ipomoea cairicascatteredGloryYellow Senna Senna pendula occasionalThe patches of littoral rainforest on Gagal Wanggan contain only modestlevels of weed disturbance predominantly Lantana and to a lesser extentBitou and Yellow Senna. The weeds exist as scattered plants most numerousalong the edges of the creek and under gaps in the canopy. Scattered plantsof Five-leaved Morning Glory (Ipomoea cairica), a vine, can be found alongthe banks of the creek.The ecological significance of this vegetation type, the small area involvedand the low density of weed occurrence give weed control in these areas ahigh priority. Further, these factors also allow the employment of low risktechniques such as hand removal. Hand pulling of seedlings and cut-andpaintusing glyphosate for larger specimens is recommended. Following theinitial and follow up control, two passes a year will be necessary formaintenance control of new seeds brought by birds and floods.A short distance across Warrell Creek similar littoral rainforest is infested withClimbing Asparagus (Protasparagus plumosus) and vigilance will be requiredto quickly identify and remove any seedlings without delay.Caring for our Country Gaagal Wanggaan Weed Management Strategy 24

Treatment schedule for littoral rainforest (and significant cultural sites)Primarytreatmenttask frequency techniqueremoval of standing plantsof all weed speciesthree times per year backpackspraying or handpullingmonitoring once per year as describedSecondarytreatmentremoval of weed seedlings twice per year hand removal(spraying ifnecessary)monitoring once per year as describedmaintenancetreatmentremoval of weed seedlingsall speciestwice per yearhand removalmonitoring once per year as describedCaring for our Country Gaagal Wanggaan Weed Management Strategy 25

Estuarine wetlandsEstuarine wetlands are found on low lying ground which is subject toinundation by the creek during the larger tide events, typically in the areas ofcreek channel abandoned by the meandering stream. They are characterisedby plants which can tolerate regular, if not necessarily frequent inundation bybrackish water. These conditions are extremely limiting to plants and theyhave a simple flora.The estuarine wetlands are for the most part open meadows of the commonsedge Juncus kraussii. There is no overstorey except around the fringeswhere the ground is slightly higher and increasingly free of tidal inundation.Swamp Oak and Broad-leaved Paperbark are found with mangroves and salttolerant grasses.This vegetation type intergrades with littoral rainforest where a small leveeexists along the creek bank.Native plant species recorded for the estuarine wetlands are listed inAppendix A.Photo 4 estuarine wetlandsCaring for our Country Gaagal Wanggaan Weed Management Strategy 26

Weed species recorded for the estuarine wetlands are listed below.Common name Botanical name occurrenceBitou bushChrysanthemoides monilifera ssp. scatteredrotundataGroundsel Bush Baccharis halimifolia scatteredRhodes Grass Chloris gayana patchesBroad-leaved Paspalum Paspalum wetsteinnii patchesFive-leaved Morning Ipomoea cairicaoccasionalGloryYellow Senna Senna pendula occasionalThe ecological limitations on these areas are reflected in their relative weedfree status. Groundsel Bush is known to be tolerant of these conditionsalthough it never thrives here. Groundsel Bush is scattered throughout theestuarine wetlands in low numbers. Groundsel Bush is a listed Noxious Weedwhich is required to be continuously suppressed and destroyed. Fortunately itis readily killed, small plants should be backpack sprayed with glyphosate andlarger specimens should be given the cut-and-paint treatment withglyphosate. Groundsel has wind blown seeds and there is no shortage ofparent material within seed transport distance so the wetland areas will needto be constantly surveyed at least once per year. The rate at which it might reestablishin these areas however, even during periods of favourableconditions, is low. On small patches of higher ground, typically relic sectionsof river levee lying between the wetland and the creek bank, are smallpatches of weed grasses brought by cattle or floods. Rhodes Grass (Chlorisgayana) and Broad-leaved Paspalum (Paspalum wetsteinnii) are best spotsprayed with glyphosate when in patches or simply hand pulled whereindividual plants.Treatment schedule for estuarine wetland areasPrimarytreatmenttask frequency techniqueremoval of standing plantsof all weed speciestwice per year backpackspraying or handpullingmonitoring once per year as describedSecondarytreatmentremoval of weed seedlings once per year hand removal(spraying ifnecessary)monitoring once per year as describedCaring for our Country Gaagal Wanggaan Weed Management Strategy 27

maintenancetreatmentremoval of weed seedlingsall speciesonce per yearhand removalmonitoring once per year as describedCaring for our Country Gaagal Wanggaan Weed Management Strategy 28

Dry Sclerophyll Forest/Tall Dry HeathThis vegetation type occurs over the bulk of the peninsula. At the southernend of the project area the canopy is around six to eight metres in height andis more or less continuous. Toward the northern end however the canopybecomes more open, there are a greater proportion of the shorter growingspecies and the tree species are generally shorter. The species involved aremore or less the same, the difference being largely structural. Because of thisthey are treated here together.Scattered throughout the dry vegetation are small clumps and scatteredindividuals of the more pioneering and fire tolerant of the littoral rainforestspecies, particularly in the more sheltered swales between the old dunes.Most are a collection of coppices which indicate that fires kill the aboveground part of the plant leaving the rootstock or lignotuber to regrow. Theseplants indicate that in the absence of fire the dry sclerophyll vegetation mighteventually be replaced by a littoral rainforest.The poor nature of the soil and the occasional fire (evidenced by blackenedtree trunks) has resulted in a low species diversity compared to dry sclerophyllcommunities on better soils in the locality. Again, the same limitations of thelandscape also contrive to limit the species diversity and the density of weedspecies and this vegetation type is regarded as being generally in goodcondition. Bitou Bush and Lantana occur as scattered plants and smallclumps with the occasional larger clump. This vegetation type abuts thewestern edge of the dune which is heavily infested with Bitou in particular, andthis edge contains the highest number of weed plants.The scattered nature of the weed population means that the primary phase ofweed control could be, generally speaking, rapidly achieved. However, a verylarge area is involved and so the work has been staged into zones. The paceof weed control across the dry sclerophyll vegetation is moderated to allowconcurrent weeding of the high priority sites and adjacent foredune.Native plant species recorded for the dry sclerophyll and tall heath are listedin appendix A.Caring for our Country Gaagal Wanggaan Weed Management Strategy 29

Photo 5. dry sclerophyll forest at southern end of peninsulaCaring for our Country Gaagal Wanggaan Weed Management Strategy 30

Photo 6. tall sclerophyll heath at the northern end of the peninsulaWeed species recorded for the sclerophyll vegetation are listed below:Common name Botanical name occurrenceBitou Bush Chrysanthemoides monilifera ssp. ScatteredrotundataLantana Lantana camara scatteredYellow Senna Senna pendulla scatteredTreatment schedule for dry sclerophyll forest/tall dry heath areas (by zone)Primarytreatmenttask frequency techniqueremoval of standing plantsof all weed speciestwice per year High volumespray and handpullingmonitoring once per year as describedSecondarytreatmentremoval of weed seedlings twice per year hand removal(spraying ifnecessary)monitoring once per year as describedmaintenanremoval of weed seedlingsall speciesonce per yearhand removalCaring for our Country Gaagal Wanggaan Weed Management Strategy 31

monitoring once per year as describedCaring for our Country Gaagal Wanggaan Weed Management Strategy 32

Threatened SpeciesNo plant species listed on State or Commonwealth Threatened Species listswere confirmed during field survey. However it is considered the project areadoes contain suitable habitat for the following listed species.Common name Botanical name Conservation Likely habitatstatusScented Acronychia Acronychia littoralis Endangered (NSW)Endangered (Federal)Hind dune, littoralrainforestWhite-flowered WaxVineCynanchum elegans Endangered (NSW) Hind dune, littoralrainforestSand Spurge Chamaesyce Endangered (NSW) dunepsammogetonSwamp Orchid Phaius australis Endangered (NSW) Wetland marginsEndangered (Federal)Swamp Orchid Phaius tancarvilleae Endangered (NSW) Wetland marginsEndangered (Federal)Leafless Cryptostylis CryptostylishunterianaVulnerable (NSW)Vulnerable (Federal)Wetland marginsCaring for our Country Gaagal Wanggaan Weed Management Strategy 33

Caring for our Country Gaagal Wanggaan Weed Management Strategy 34

Essential ReferencesWinkler, MA, Cherry, H and Downey, PO, (eds) (2008). ‘Bitou BushManagement Manual: current management and control options for BitouBush (Chrysanthemoides monilifera ssp. rotundata) in Australia’.Department of Environment and Climate Change (NSW), Sydney.Broese van Groenou, E.A. and Downey, PO. (2006). ‘Best PracticeGuidelines for Aerial Spraying of Bitou Bush in New South Wales’.Department of Environment and Conservation (NSW), Hurstville.Van Oosterhout, E. (2004). ‘Lantana: Current management and controloptions for Lantana (Lantana camara) in Australia’. Department of NaturalResources, Mines and Energy (QLD), Brisbane.Ensbey, R, and Johnson, A. (2007). Noxious and Environmental WeedControl Handbook: A guide to weed control in non-crop, aquatic andbushland situations, 3 rd Edition. Department of Primary Industries (NSW),Orange.Hamilton,M.A., Winkler, M.A., Downey,P.O., (2008) Native plant species atrisk from Bitou Bush invasion: A field guide for New South Wales.Department of Environment and Climate Change (NSW), Hurstville.Hughes, N.K., King, SA., Burley, A.L. and Downey, P.O., (2008), MonitoringManual: for Bitou Bush control and native species recovery. Departmentof Environment and Climate Change (NSW), Hurstville.Caring for our Country Gaagal Wanggaan Weed Management Strategy 35

APPENDIX APlant species recorded for Gaagal WanggaanCommon NameBotanical NameCoastal Wattle Acacia longifolia var. spohorae c sBeach Acronychia Acronychia imperforata o sWhite Acronychia Acronychia oblongifolia sRiver Mangrove Aegicerus corniculatum cBeach Bird’s Eye Alectryon coriaceus s oBlack She Oak Allocasuarina littoralis sNative Elm Aphananthe philippensis sRed Ash Alphitonia excelsa s c oPink Laceflower Archidendron grandiflorum oCoogera Arytera divaricata sCrow’s nest Fern Asplenium australasicum oGrey Mangrove Avicennia marina cCoastal Banksia Banksia integrifolia c sSaw-leaved Banksia Banksia serrata sRound-leaved Red-pea Bossiaea rhombifolia cBreynia Breynia oblongifolia o c sBrush Ironbark Bridelia exaltata oBeach Pigface Carpobrotus glaucescens cRed Olive-plum Cassine australis o cSwamp Oak Casuarina glauca cSilky Celtis Celtis paniculata sSmooth Clerodendrum Clerodendrum floribundum o s oCommelina Commelina cyanaea s s sCordyline Cordyline stricta sSwamp Lily Crinum pedunculatum o o oTuckeroo Cupaniopsis anacardioides s s oWax vine Cynanchum carnosum oA sedge Cyperus sp. oBeach Flax Lily Dianella congesta sBlue Flax Lily Dianella caerulea sforedunelittoral Rfwetlanddry scleroCaring for our Country Gaagal Wanggaan Weed Management Strategy 36

Native Yam Discorea transversa o oYellow Tulip Drypetes australasica oHairy Rosewood Dysoxylum rufum sBanana Bush Ervitamia angustisepala s sPink Bloodwood Eucalyptus intermedia o cFlooded Gum Eucalyptus grandis oRibbonwood Euroschinu falcata o s oWombat Berry Eustrephus latifolius s oMilky Mangrove Excoecaria agallocha cSmall-leaved Fig Ficus obliqua oRusty-leaved Fig Ficus rubiginosa oCane Flagellaria indica sGuoia Guoia semigauca o cGuinea Flower Hibbertia scandens s cA Hibbertia Hibbertia sBlady Grass Imperata cylindrical s cA Rush Isolepis sp. sFoambark Jagera pseudorhus o cCommon Rush Juncus kraussii cCoast Tea Tree Leptospermum laevigatum c oTea tree Leptospermum liversedgei cTea Tree Leptospermum polygalifolium cSmall-flowered Beard Heath Leucopogon parviflorus o cCabbage Palm Livistona australis cPink Lobelia Lobelia alata o oMat Rush Lomandra longifolia o cBurny Vine Malasia scandens sMilk Vine Marsdenia lloydii o sBroad-leaved Paperbark Melaleuca quinqenervia c oPrickly Paperbark Melaleuca styphelioides cYellow Pear-fruit Mischocarpus pyriformis cMonotoca Monotoca elliptica sBoobialla Myoporum acuminatum sPigeonberry Ash Olea paniculata sBroad-leaved Basket Grass Oplismenus aemulus o oNarrow-leaved Basket Grass Oplismenus imbecilus cCaring for our Country Gaagal Wanggaan Weed Management Strategy 37

Wonga Vine Pandorea jasminoides oSaltwater Couch Paspalum vaginatum cNative Passonfruit Passiflora herbertiana oSickle Fern Pellaea falcata sBroad-leaved Geebung Persoonia stradbrokeinsis cNarrow-leaved Geebung Persoonia virgata cPhragmites Phragmites australis cElkhorn Fern Platycerum bifurcatum oPomax Pomax umbellata cBracken Pteridium esculentum s cScrub Mutttonwood Rapanaea howitiana sNative Guava Rhodomyrtus psidioides o c sSupplejack Ripogonum album sBeach Spinifex Spinifex sericeus cSand Couch Sporobolus virginicus cSarsparilla Smilax australis o c sSnake Vine Stephania japonica s s o sLilly Pilly Syzygium australe sLilly Pilly Syzygium luehmannii sLilly Pilly Syzygium smithii s s sBeach Spinach Tetragona tetragonoides cKangaroo Grass Themeda australis sViolet Viola hederacea s s sWilkea Wilkea huegeliana cPrickly Couch Zoysia macrantha s sWeed Species Recorded for Gaagal WanggaanCommon NameBotanical Nameforedunelittoral Rfwetlanddry scleroGroundsel Bush Baccharis halimifolia sRhodes Grass Chloris gayana oBitou BushChrysenthemoides moniliferassp. rotundataPennywort Hydrocotyle bonariensis sc o o sCaring for our Country Gaagal Wanggaan Weed Management Strategy 38

Five-leaved Morning Glory Ipomoea cairica o oLantana Lantana camara o c sBroad-leaved Paspalum Paspalum wettsteinii o oPassiflora subpeltataYellow Senna Senna pendula s oDeadly Nightshade Solanum nigrum o oC – common, S – scattered, o - occasionalCaring for our Country Gaagal Wanggaan Weed Management Strategy 39

APPENDIX BFormulation and mode of action of herbicides recommendedHerbicide name: GlyphosateTrade names: Roundup, Roundup Biactive, Weedmaster Duo plus many othersFormulation: N-phosphonomethyl glycine (usually as an isopropylamine salt)Description: a broad spectrum, non selective systemic herbicide that can be used tocontrol a wide range of broadleaf plants and grasses. It is translocated from theleaves or cut stump to actively growing parts of the plant. Glyphosate works bydisrupting an essential plant enzyme (5-enolpyruvylshikimic acid 3-phosphatesynthase or EPSPS) in the shakimic acid pathway and inhibits the production ofessential aromatic amino acids. EPSPS and the shakimic pathway are present inplants, fungi and bacteria but not in animals.Environmental fate: Glyphosate is metabolised by the mode of action describedabove on sprayed plants.Overspray is readily and strongly adsorbed to soil particles particularly colloids andorganic matter. It is broken down in the soil by microbial activity, the rate ofdecomposition is governed by temperature and organic content of the soil.Glyphosate is reduced to naturally occurring compounds such as carbon dioxide,inorganic phosphate and others. The average half life of glyphosate in soil is 32 days.Herbicide name: metsulfuron methylTrade names: Brush Off, AssociateFormulation: Metsulfuron methylDescription: a sulfonylurea herbicide which provides selective pre and postemergence control of broad leaved plants and some annual grasses. Metsulfuronmethyl inhibits the enzyme acetolactate synthase (ALS) which is required forsynthesis of amino acids necessary for cell division. ALS is not present in animals.Environmental fate: Metsulfuron methyl is metabolised by the mode of actiondescribed above in plants. It is broken down by microbial activity and chemicalhydrolysis. The half life is dependant on soil pH, and is from 5 days in acidic soils to69 days in alkaline soils. Leaching of metsulfuron methyl is greater in alkaline soils.Caring for our Country Gaagal Wanggaan Weed Management Strategy 40