Trillium grandiflorum carpet in our oak woods.

This is the time of year for Trilliums. We have scattered flowering plants in the oak savannas, but the major display is in the north woods, easily visible by driving slowly along County F.

This year the display is larger than we have ever seen it. It extends along almost a half mile of the lower area of woods. I attribute this large display to the successful woods burns we have had the past 10 years, including last October. As a result of the last burn, the carpet of oak leaves was removed, making it easier for the plants to send up shoots.

We burn these woods in the fall partly to keep from damaging the spring ephemerals. A spring burn in these woods would have a detrimental effect, since it would kill the new shoots. In the fall the Trillium perennating structures lie deep under the soil where the fire cannot reach them. Through the years that we have been doing restoration work at Pleasant Valley Conservancy, we have seen the Trillium carpet continue to spread.

Typical carpet of Trillium grandiflorum in the north woods

Trillium grandiflorum forms short tuber-like rhizomes, which participate in its gradual spread. Seeds are also formed, and are spread by ants. According to some sources, seeds are also dispersed by yellow jackets, other flying insects, and white-tailed deer, which may explain why we find isolated plants scattered through our ridge-top savannas, a long way from the woodland carpet.