Effect of simulated goose grazing on yield of autumn-sown barley in north-east Scotland.
Goose (Anser anser and A. brachyrhynchus) grazing on autumn-sown barley was simulated in the field in NE Scotland by removal of 25, 50, 75 or 100% of the green leaves in Mar. and late Apr. in 1985 and 1986. Clipping decreased growth rate, grain yield, number of ears/m2, number of grains/ear, 1000-grain wt and straw yield. The amount of weed in the crop increased with the degree of clipping in 2 of 4 late treatments but early clipping had no effect in either year. Late clipping resulted in lower yields of grain and straw than did early clipping, but this was explained entirely by the greater amount of material removed rather than by an effect of timing as such. Goose droppings had no effect on the total grain or straw yield (although they produced a significant reduction in 1000-grain wt) probably because the amount of nutrient they supplied was negligible when compared with fertilizer application. Yield reductions with simulated grazing were similar to those associated with natural goose grazing with the same low levels of removal of material.