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64As wooI has become a less important cornmodityand the importance of producing prime lamband cheese has taken over, the need for tmnshumanceis no longer pammount, lhe result beinglhal more and more flocks of merino slay all lheyear in their original provinee. From lhe aboyebreeds and crossbreeds enough lamb is producedto be industrially exploited. Merino is now exploitedfor its wool in Auslralia, where populationdensity is low and there are similar Mediterraneanconditions to those found in the west ofthe IberianPeninsula.The Manchego syslem of husbandry (5 inFig. 3.10)To the south ofMadrid, the Meseta is al a loweraltitude than to the north (average altilude 600 mas opposed to 800 m), the summer is hotter anddrier, and thus lhe gmzings are rougher and poorin quality. Less arable land is dedicated to pastureor scrub, most of it being under cultivation, withgrapes as lhe main crop. Frequently olive grovesalternate lVith the vineyards, and occasionallyolives, vines and almond trees all grow in the samefield.The eombination of a lemperale winter, deepsoil and the diversity of crops, (including fodderbarley, oats and legumes grazed in lhe field), opensout lhe possibilities of a much greater variety indiel for the sheep during lhe lactation periodo Themilking ofsheep for the manufacture of cheese is avery old industry. Vines and trees supply a soureeof [oad in auturnl1, and modern irrigation hasmeant that the small flocks of40 to 60 sheep can bekept near the centres of habitation in La Mancha.However, the larger flocks (200-250 sheep) needmore extensive areas of uncultivated land wherethere are wide sheep tmils. Usually they are kepton large provincial eslates which were previouslyassociated lVith lhe mediaeval Ordenes Militares(Calatmva, Alcántara) on the southern frontiers ofthe Christian Kingdoms.As wilh olher breeds of sheep, the Manchegagraze on the stubble in summer and on theuncultivated land around in winter. The number offomge crops grolVn (such as cereal-legume mixturesfor grazing by sheep) have increased but ther.eis not sufficient humidity lo produce summerforage, like some of lhe ¡egumes sown in thenorthern part of the Caslillian Meseta. The deepPEDRO MONTSERRAT and FEDERICO FtLLATsoil pennits the dry farming of lucerne and also,where thcre is irrigation, a variety of forage eropsplus lucerne. Pastures are domina ted by roughgrasses as Aegylops, Bro11lus and Taenialherum,logelher lVith Medicaga and other annuallegumes.To sum up, we find a great diversity lVilhin thisenvironment, a variety of different products evenin autumn lacking pasture in Meditcrraneanclimate and a breed of sheep resislanl to both heatand drought. Given lhe possibilities for the furtherexpansion of foragc crops, using undergroundwater for irrigation, the Manchega sheep couldhave a promising futufe.A greater diversily in diel can be provided by useof vine shoots and the leaves of trees in autumn,thereby avoiding the destruction of annuals in aseason which is critical for their establishment. Asmenlioned aboye, the sheep of this region stand upwell to the extreme summer heat and continue toproduce milk, which is IVhy they have been selectedto populate this Mediterranean type habitat.Thc Segureña type of grassland syslem (6 IIIFig.3.10)To the soulheasl of the Peninsula the clima tebecomes drier and lhe vegetation woodier. Becauseof these conditions there are more goats and fewersheep. As well as the sheep indigenous to thecoastal regions (GII!rra in Valencia and Alicante), ahardy animal which resists heat and drought, thereis a second breed of sheep, the Segureña, scalteredthroughout the region. The lalter is similar lo lheManchega sheep but produces less milk and is af ahardier slock.The vegetalion covering the area inhabited bythe Segureña sheep is mainly rosemary (RosmarinllsojJicinalis) and rush (Lygell/1/ spar/llm) lVithtough grasses (AgJ'0pYI'OJl, Bl'achypodium, Helictotrichonfilifalill/1/, S/ipa, etc.) and scrubby pastures,thus producing conditions for grazing which wouldnot be tolemled by lhe more productive breeds ofsheep. Traditionally, the land is used for lheproduction of rushes and in lhe valleys, interspersedbetween the .arid mountains, some cerealsare cultivated. Given these circumstances it wouldseem sensible to encourage the expansion of theSegureña breed, thus increasing the production oflambs which are much in demando
THE SYSTEMS OF GRASSLAND MANAGEMENT IN SPAlN65The Dehesa lype of grassland in lhe wesl of lheIherian Peninsula (7 in Fig. 3.10)In the wesl, due lo the extreme summer droughtand the poomess of the soil, lhe cultivation ofcereals is not profilable, and instead there are largeareas of wooded pasture-Iand supporting a largerange of livestock, such as swine, sheep, cattle,horses and donkeys. In some areas there are alsoJIocks of domestic fowl of various types. Thedensity of trces ¡ocreases as Qfie gocs further 80uth,thus protecting the land surface from the intenseheat and insola tion. There is also an increase in thenumber of swine.The tradition of use of forest c1earings for thegrazing of animals is left over from earJier epochs.Al arre time, when demographic pressure was notso great, other mountain areas were grazed in thesame way; but nowadays it is a custom whichpersists mainly in the wes!. Here the originalevergreen oak has been preserved; and, where thisis not so, a more productive oak with a large sweetacom has been planted in woodland pastures.Historically speaking (Balcells, 1978-1982),from the time of the Reconquista lhe land wasdivided into large estates (100-500 ha). There hasbeen little change in this respect due to the lowfertility of the soil, a fact which has prec1udedintensive cultivation in the area. Only in Tierra deBarros (Extremadura Region), and along narrowriver valleys, properties are smaller and intensivecultivation takes place.If one considers a typical or average dehesa, 10to 30% of the land may be under cultivation whilethe rest is employed in different ways which varyfrom Salamanca to Huelva. In the westem sectorof Salamanca there are lwo main methods of usingthe land, one so-called al tercio and a secondnamed a cuatro hojas. Al tercio means that 2/3 ofthe land is used for cultivation of cereals while athird lies fallow. In the second, 30% of the land isdedicated to growing cereal which then providesslubble for grazing (Gómez Gutiérrez, 1982 inBaleells, 1978-1982). Where there is a greaterdensity of trees, grazing continues until it isinvaded by scrub or toxic plants and a system ofrotation musl be applied in order to c1ean the area.The dense evergreen oaks are intensively pruned,before ploughing lhe soil, and cereal is sown theyear after. This process conlinues until lhe soilbecomes impoverished and has to be abandoned.The abandoned fields of stubble are given over tograzing, and vegetation becomes progressivelydenser.The watercourses and hollows found betweenareas of cultivation provide productive pastureswhich are cut sometimes, especially where fertilizerhas been applied; it helps lo keep the pasture elearof undergrowth. The principal plants fOllnd hereare Trifolillll1 striafllm with T. slIbterraneunJ andAgrostis castellana.The Morucha cow is typical of dehesas ofSalamanca, and it keeps the paslure both elean andshort for subsequenl grazing by the EnlrefinnCastellana sheep. This is the limit of the zonewhere the Iberian pig occurs, the production ofacorns being scarce and variable from year to year.Even so, the herdsmen have been responsible forplanting acoms from which many of lhe evergreenSalamanca oaks grow. By rooting in lhe soil, theIberian pig causes a series of microchanges in thepaslures, thus creating a diversity used efficientlyby the ruminants. Finally, the common Spanishturkey (Pavo mexicano) feeds on acoms, and al thesame time controls the populations of sorne inscctsand molluscs.In Extremadura, acorn production is greater andthere are many more pigs, with a consequentdecrease in cattie density. The Blanca Cacereñacow is now practically non-existent, and variousbreeds ofcow can be seen locally. The environmentis optimal for merino sheep, and there are someJIocks resident all the year round while others stillpractice lranshumance to the Cantabrian Mountains,protected from wolves by the mastín extremeño.This big shepherd dog carries a collar withnails and fights with wolves, bul when animalssuch as horses and Cantabrian autochthonouscows graze without shepherd or dog the wolves kilisome - between 1974 and 1979 236 animals,predominantly colls, were killed in Aslurias (Branaet al., 1982; see also López et al., 1981).Approaching the west side of the Sierra Morena(Sierra de Tudia and Aracena) one finds anincrease in the number of herds of Retinta cows,which maintain the pastures elean without the needto resort to cultivation. In these dehesas there is agreat number of evergreen oaks, even along lheedges of walerways. The increase in tree densityprotects against insolation and feeds the greatnumber of pigs. This is the centre of lhe region of
Page 4 and 5: 40day' when the areas of important
Page 6 and 7: 42 PEDRO MONTSERRAT and FEDERICO FI
Page 8: 44animal husbandry in the past and
Page 12 and 13: 48Information on the distribution o
Page 14 and 15: lA GRASSLAND(%)1W1! >75~50-75825-50
Page 16 and 17: @'""+ ...."4@ o l. European-Atlanti
Page 18 and 19: 54niga (Valle de Cabuérniga), on t
Page 20 and 21: 56However, nowadays the autumn graz
Page 23: THE SYSTEMS QF GRASSLAND MANAGEMENT
Page 26 and 27: 62made up of hard-leaved grasses (A
Page 30 and 31: 68There are more diffieulties in th
Page 32: 70Selecciones del Reader's Digest,

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