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Individual study: Hebridean sheep grazed more purple moor grass than Swaledale sheep, but the resulting density of purple moor grass and heather did not differ in England

Published source details

Newborn D. (2000) The value of Hebridean sheep in controlling invasive purple moor grass. Aspects of Applied Biology, 58, 191-196


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Use traditional breeds of livestock Farmland Conservation

A small, replicated study from 1992 to 1996 of four pasture plots in North Yorkshire, UK (Newborn 2000) found that Hebridean sheep (a minority breed) grazed more purple moor grass Molinia caerulea than Swaledale sheep (traditional upland breed), but the resulting density of purple moor grass and heather Calluna vulgaris did not differ. Hebridean sheep grazed significantly more purple moor grass leaves than Swaledales (61% vs 23%). But the density of purple moor grass leaves did not differ between Hebridean (2389 m²) and Swaledale plots (2798 m²). Overall, cover by heather did not change over time. In the Hebridean plots, heather cover doubled in the first four years (12% to 29%), then declined (22%), the overall increase was 3.7%/year. In Swaledale plots, cover increased over the first two years (3% to 7%), then declined dramatically to 1%, with an overall decline of 1%. Two areas of pasture dominated by purple moor grass, ungrazed for two years and unburnt for ten, were divided into two plots of 2 ha, one grazed by Swaledale sheep, one by Hebridean sheep (99 kg live weight/ha) between May and September. Numbers of grazed and ungrazed purple moor grass leaves were sampled within two quadrats (0.5 x 0.5 m) and lengths of grazed/ungrazed leaves measured at 100 points across plots following sheep removal in September each year. Plant species were sampled using a point sampling technique along a 15 m transect (45 cm intervals).

 

Control weeds without damaging other plants in conservation areas Farmland Conservation

A small, replicated study from 1992 to 1996 of four pasture plots in North Yorkshire, UK (Newborn 2000) found that Hebridean sheep grazed more purple moor grass Molinia caerulea than Swaledale sheep, but the resulting density of purple moor grass and heather Calluna vulgaris did not differ. Hebridean sheep grazed significantly more purple moor grass leaves than Swaledales (61% vs 23%). However, the density of purple moor grass leaves did not differ between Hebridean (2389 m²) and Swaledale plots (2798 m²). Overall, cover by heather did not change over time: in the Hebridean plots, heather cover doubled in the first four years (12% to 29%), then declined (22%), the overall increase was 3.7%/year. In Swaledale plots, cover increased over the first two years (3% to 7%), then declined dramatically (to 1%), with an overall decline of 1%. Two areas of pasture dominated by purple moor grass, ungrazed for two years and unburnt for ten, were divided into two plots of 2 ha, one grazed by Swaledales, one by Hebridean sheep (99 kg live weight/ha) between May and September. Numbers of grazed and ungrazed purple moor grass leaves were sampled within two quadrats (0.5 x 0.5 m) and lengths of grazed/ungrazed leaves measured at 100 points across plots following sheep removal in September 1992-1996. Plant species were sampled using a point sampling technique along a 15 m transect (45 cm intervals) using an eight pinned frame with the tallest vegetation touching each pin identified.