Effects of treading perennial ryegrass (Lolium perenne L.) and White Clover (Trifolium repens L.) Pastures in winter and summer at two soil moisture levels

Abstract Two uniform perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L.) pastures, growing in a silt loam, were used (winter 1957 or summer 1958) to investigate the effects of periodical treading, where the soil was at 2 different soil moisture levels. Spray irrigation and mature Romney sheep were used. All treadings, especially where the soil was wet, reduced measured herbage yields. Total yields of dry herbage in lb per acre during winter 1957 included: not trodden—1,980; moist soil, 18 sheep treatment—1,670; wet soil, 18 sheep—270; S.E. ± 62; and others during summer 1958 included: not trodden—2,280; moist soil, 18 sheep—1,080; wet soil, 18 sheep—230; S.E. ± 74. Perennial ryegrass was consistent in being relatively tolerant of treading, while white clover was tolerant in the summer. Thus the proportion of perennial ryegrass increased in the trodden pastures, while Poa annua L. volunteered in bare spaces. Reduced yields appeared, in the main, to be due to the lower vigour of a ...