Publication Date
1997
Description
The effects of ceasing fertiliser inputs to perennial ryegrass/white clover swards, combined with patterns of seasonal grazing, on soil nutrient status, floristic composition and animal production (ewes and single lambs) were studied in a long-term experiment at three upland sites in Scotland. Four unfertilised treatments had a factorial combination of seasonal grazing in summer and autumn at two sward heights (4 and 8 cm). There was also an ungrazed, unfertilised control and a fertilised treatment (140 kg N/ha plus maintenance P and K), grazed at 4 cm sward height in both seasons. All treatments were imposed annually from 1990/91. By 1995 there had been no significant changes in soil pH or soil nutrients following the removal of fertiliser inputs. Sown species were dramatically reduced in the ungrazed swards. In contrast, changes in species composition were smaller in the unfertilised, grazed treatments and consequently there was little reduction in lamb performance in some treatments.
Citation
Marriott, C A. and Gordon, I J., "Extensification of Sheep Grazing Systems: Effects on Soil Nutrients, Species Composition and Animal Production" (2024). IGC Proceedings (1997-2023). 2.
https://uknowledge.uky.edu/igc/1997/session15/2
Included in
Agricultural Science Commons, Agronomy and Crop Sciences Commons, Plant Biology Commons, Plant Pathology Commons, Soil Science Commons, Weed Science Commons
Extensification of Sheep Grazing Systems: Effects on Soil Nutrients, Species Composition and Animal Production
The effects of ceasing fertiliser inputs to perennial ryegrass/white clover swards, combined with patterns of seasonal grazing, on soil nutrient status, floristic composition and animal production (ewes and single lambs) were studied in a long-term experiment at three upland sites in Scotland. Four unfertilised treatments had a factorial combination of seasonal grazing in summer and autumn at two sward heights (4 and 8 cm). There was also an ungrazed, unfertilised control and a fertilised treatment (140 kg N/ha plus maintenance P and K), grazed at 4 cm sward height in both seasons. All treatments were imposed annually from 1990/91. By 1995 there had been no significant changes in soil pH or soil nutrients following the removal of fertiliser inputs. Sown species were dramatically reduced in the ungrazed swards. In contrast, changes in species composition were smaller in the unfertilised, grazed treatments and consequently there was little reduction in lamb performance in some treatments.
