Influence of Cattle Stocking Rate on Browsing of Norway Spruce in Subalpine Wood Pastures

Abstract

In the Swiss Alps, 15% of Swiss mountain forests are grazed during summer, mainly by cattle. The forest laws of various Swiss cantons characterise forest grazing as a detrimental form of land use and stipulate that this grazing practice should be restricted. However, little is known about tree damage actually caused by cattle. Seven subalpine ranges in the Swiss Canton Grisons, grazed by cattle at different stocking rates, were investigated. The condition of naturally regenerated young trees (Picea abies (L.) Karst.) was assessed before and after the cattle grazing period. In order to characterise the influence of wild ungulates on the young trees during winter, the assessment of tree condition was repeated in the proximate spring. In total, 4% of the young trees were browsed on the apical shoot, 10% were browsed on lateral shoots, 13% of the trees showed other damage. The variation among ranges could almost completely be explained by the cattle stocking rate (livestock units per hectare). During winter, wild ungulates browsed 3 times as many young trees as the cattle during summer. The results suggest that cattle stocking rates on subalpine wood pastures should not exceed one livestock unit per hectare in order to avoid intensive browsing and other damage by cattle on young Norway spruces.

The larch wood pasture: structure and dynamics of a cultural landscape

“…Mayer et al (2006) suggested to hold down a grazing pressure threshold of 1 LUּ ha -1 or to provide time intervals without grazing (Van Uytvanck et al 2008). Heavy grazing pressure followed by periods of moderate grazing is often associated to the onset of tree regeneration in many sites (Mast et al 1997).…”

“…Livestock grazing only affects grasses and forbs, instead wildlife and goats browsing directly influences shrubs and trees regeneration growth. Thus, cattle grazing can be considered less dangerous than wild ungulates browsing (Mayer et al 2006) because only a high cattle stocking rate may increase the risk of unintentional trampling on trees. For these reasons, landscape management should find a balance between the conservation of open areas and wood pastures and natural encroachment of trees.…”

Habitat improvements with wildlife purposes in a grazed area on the Apennine Mountains

“…Pastoral activity has been one of the sectors mainly affected by abandonment of land and extensification of the less productive areas (Didier, 2001;Mayer et al, 2006;Peeters, 2008;Van den Pol-van Dasselaar et al, 2008). One of the most observable consequences of land abandonment is the reduction of open surfaces located in marginal areas, like meadows and pastures once intensively utilised by domestic animals (Messeri et al, 2007), but which are now subjected to the diffusion of shrubs and undesirable plants (Lombardi et al, 2001).…”

Experimental determination of the effects of cattle stocking density and grazing period on forest regeneration on a subalpine wood pasture

“…This implies that the larches might compensate for the biomass loss due to browsing in the subsequent growing seasons, if the fields are grazed at lower stocking densities. During our own studies on established wood pastures grazed at a stocking density of 0.4 LU·ha -1 , no single larch was browsed by cattle [31]. An important reason for the larches of the present study to be used as a nutrient source could have been their origin from a tree nursery located on a lower altitude where the soil contains more nutrients.…”