How deer change the landscape.

• Position: Forests

It widely is known that the white-tailed deer is a nonstop eater. Unless it is sleeping or fleeing from a predator, the keystone North American herbivore nearly always is nibbling. Ecologically, deer herbivory is a fairly well-understood phenomenon. The presence, abundance, and reproductive success of many plant species directly are affected by deer, whose populations are orders of magnitude greater in some regions than they were before European settlement.

Now, scientists are looking beyond herbivory to better understand the indirect effects of deer on North American forest landscapes. In particular, scientists are interested in how the animal's presence and behaviors affect the composition and overall health of the wildflowers and other herbs--what scientists call understory communities--that blanket the forest floor.

In the Journal of Ecology, lead author Autumn Sabo, plant ecologist at the University of Wisconsin, Madison, and her colleagues detail how deer affect forest plant composition by altering facets of the forest environment, including light availability, soil compaction, and the thickness of a particular layer of soil.

Archaeological evidence suggests that deer once were far less abundant in eastern...