Timing and intensity of herbivory: Its influence on the performance of clonal woodland herbs

Herbaceous woodland species account for a significant amount of the biodiversity of temperate deciduous forests. A wide diversity of life-history strategies is known for woodland herbs, and several systems have been used to categorize the range of life-history characteristics. Clonal growth, one common feature of many woodland herbaceous species, provides several benefits including the ability to respond to disturbances by sharing resources among ramets. There is evidence that resource sharing is common among ramets of some species of woodland herbs but not others. Herbivory is a common form of disturbance among woodland herbs, but little is known about effects of the timing and intensity of herbivory. In this paper, we use an existing system of classification of life-history traits of clonal species to make predictions about how woodland herbs would respond to the timing and intensity of defoliation. Examples from a preliminary study in Maryland, USA, are used to demonstrate that the timing and intensity of herbivory can play an important role in determining patterns of future growth and resource allocation.