Woolly Cupgrass Biology Woolly cupgrass is an annual grass, reproducing from year to year only by seeds. However, certain biological traits of this species make it more competitive than many other annual grasses. Seed Characteristics Figure 3. Wooly cupgrass inflorescence showing spikes and seeds. Woolly cupgrass is a prolific seed producer, generating over ten times the number of seeds as giant foxtail.
Seed dormancy increases soil longevity.
In addition, seeds are very large, which allows for germination from soil depths of up to six inches. Seeds germinate early compared to some other annual grasses. Seedling emergence was evaluated twice weekly throughout the 1995 growing season. The emergence patterns are shown in Figure 4. The graph shows that most woolly cupgrass emergence occurred more than two weeks ahead of giant foxtail.