the systems of grassland management in spain - Publicaciones del ...

56However, nowadays the autumn grazing of acornsby pigs (montanera) has disappeared and the lachasheep are grazing all the year in foresl and serubs,logether wilh an inereasing number of horses. Thepony (jaca navarra) is also typieal of lhis landseape.Al lhe present time, the more intensified agrieullureis limited to the deep vaIley soHs, but the fieldsare aIways surrounded by hedges, shrubs and trees,mainly relicts fram the anclent forests. Permanentgrasslands are dominant on slopes, situated bolowthe grazed forests.Pastures with Brachypodium pinnatum dominanl,togelher with Erica vagans or braeken(Pteridium aquilinum) show bad grazing teehniquesin lhis landseape, promoted by the abandonmeutofmarginallands. Ecological diversity is favouringgrazing husbandry in this attractive part of Spain.The communal organizalion and other historiealinfluences, together with an improved road system,will be helpful in improving a new animalhusbandry.Aragón (2b in Fig. 3.10)The boa/m·es. The villages of lhe HuescaPyrenees, like many other agrieultural provinees ofSpain, retained sorne plots of forest from lhecommunal property. Traditionally these plols weregrazed by traetÍon animals (oxen, horses, mulesand donkeys). They are ealled dehesa boyal, boveral01' boalar, meaning a surface reserved fOI oxeo. Thedominant tree is a local oak or quejigo (manyslrains ofQ.faginea) or in the more Mediterraneanpart lhe evergreen oak (Q. ilex subsp. I"Otundifolia).Until recent times (1940-1960) shrubs were verysparse under the trees, and were eliminated byheavy grazing, but since the use of mechanicflltraetors has become frequent, this special grasslandhas evolved towards a natural forest.Every hamlet in this part of the Pyrenees has itsown boalar wilh an area of 2 to 10 ha according tothe exigences of ploughing. Under this very sunnyclimale, good grassland can be proteeted by acanopy screen of pruned trees. Animal dung andurine ereate good eonditions for grass under heavygrazing pressure. This special sod and very produetivelurf should be used in the future todiversify the grassland in every mounlain village,mainly because it is aeeessible and well adapted tograzmg.PEDRO MONTSERRAT aud FEDERICO FILLATDevelopmenl of meadows from fields of sainfoinand lucerne. Same characteristics of mountainmeadows are summarized in Fig. 3.13. The graph(Fig.3.13c) explains two importanl effects onquality of meadows. The ordinate axis is a qualityindex for the firsl eul [DNDF~Digestibility of theeeIl-wall material (neutro-detergent fibre - Goeringand Van Soesl, 1970-)] and the abseissa theeutting date. The oeeanic type of climate of themore westerly sites (Hecho and Siresa) wilh amilder spring faeilitate an early cut as camparedwith Anciles and Cerler. The hay quality is betterat lower (Hecho, 833 m) than al higher altitude(Siresa, 1050 m), and the same is lrue in theeomparison belween Anciles (1200 m) and Cerler(1500 m) in the easlern Alto Aragón.Table 3.1 shows the location of eight samplingsiles on present-day grassland: sorne of them arecoming from old fields (2, 3 and 5), others fromlucerne fields (1 and 4) and finally one comesdireetly from a cleared foresl (8). In the lasl yearssome fieIds were sown with selecled grassland seed(6 and 7). In general, we can see lhe height ofgrasses and the stabilization of legumes at lowlevels.Table 3.2 summarizes the total production(eutting and grazing) of a typieal meadow of lhisreglOll.Table 3.1 emphasizes the effeet of manuring onlhe first cut (June 1977) under diversified eondi'tions of mountains. Lucerne remains many yearstogether with new-coming spontaneous species,and maintains fertility in the topsoi!. In the sameway, sainfoin improved soil ferlilily on dry slopeson limes tone. In order to establish new meadows, itwill be essential to use adapted legumes and grasseslike eoeksfoot (Dactylis glomerata) or other seleetedseeds, always wilh heavy manuring.Thc borda for hay and animals. In the SpanishPyrenees, bordas are not very frequent except in thecenlral region where the big valleys are suitable forimportant hay produetion. Figure 3. 14C shows thebig dissimilarily between lhe easlern and westernsides of the Monte Perdido, in lhe centre of thisseelion. The Aneient Pyrenees (of Primary orPalaeozoie age) are more important lo lhe east,while the Sierras Interiores (more reeent, ofOligocene age) are predominant in lhe west;consequently, the big valleys are frequenl in theeast. The altitudinal distribution of bordas is