Effect of defoliation frequency on simulated swards of ryegrass, tall fescue, and a 50/50 mixture of the 2 species

Simulated swards of ryegrass, tall fescue, and a 50/50 mixture of the 2 species were established in pots, placed in a controlled‐environment room, and harvested at intervals of 10½h, 21, 42, and 63 days. Dry matter production increased with less frequent defoliation but tiller numbers were highest under the 10½‐day defoliation interval. Digestibility tended to decline at defoliation intervals longer than 21 days. In the mixed sward, tall fescue was more competitive under a 63‐day defoliation interval and less competitive under a 21‐day defoliation interval. These results highlight the importance of assessing competition between pasture species in a mixed sward under more than one defoliation regime.