The alteration of ground cover and total herbage and browse production under proper grazing in a silvopastoral system

The establishment of a silvopastoral system in a Mediterranean environment is expected to fill up the feed gaps of the grazing animals for winter and summer. The aim of this research was to study the alteration of ground cover and total herbage and browse production under proper grazing in a silvopastoral system. The experiment was conducted at Scholari village of Thessaloniki, Greece, in a 1.7 ha area, which was fenced in order to exclude the uncontrolled grazing and was divided into six equal size plots. Three of them were randomly assigned to be grazed while the other three remained ungrazed. In all plots, two woody fodder species, Robinia pseudoacacia and Morus alba were planted separately at three different spacings (1.5mx1.5m, 2.5mx2.5m and 3.5mx3.5m). Half of the plots, planted with the woody species, were ploughed and seeded while the other half remained undisturbed. Dactylis glomerata cv. palestina was seeded into Robinias’ plots while Trifolium subterraneum cv. Mt Barker was seeded into Morus’ plots. The experimental design was the split-split plot with incorporated factors and three replications. For the comparison of the incorporated factors a completely random design was applied. The research has shown that proper grazing reduced ground cover by 4.4% in three years. Ground cover in the ungrazed plots was 92.6% in 1997 while in 1999 was increased to 94.3%. Regardless of grazing, the groung cover of Dactylis glomerata was decreased by 52.6% and that of Trifolium subterraneum by 38.2% at the end of the third year. Grazing seemed to be more harmfull for Dactylis glomerata (74% decrease) than to Trifolium subterraneum (20.6% decrease) along the three years. Proper grazing decreased the total production of the silvopastoral system compared to the ungrazed plots. The browse production of the woody species was decreased by 37% while the herbage production by 31%.