This project will study the impact of an outbreak of the forest tree caterpillar (Malacosoma disstria) on tree seedling establishment, productivity and community structure of temperate forests. Outbreaks of insects that defoliate whole forest canopies occur sporadically and may last only a year or two. For this reason, they have received limited study. However, considering the long lifespan of trees, defoliation events may be an important factor determining the long term dynamics and succession within forests. Prior research has focused on the negative impacts of defoliation on tree growth and survival; far less attention has been given to the positive impacts on tree seedling establishment associated with increased understory light and soil nutrients. This project takes advantage of an ongoing, massive outbreak of forest tree caterpillars in a section of lower Michigan that encompasses previously established long term research sites. The data on tree dynamics from the long term study provide a rare baseline against which the impact of the insect outbreak can be compared. It is critical that this research start immediately in order to collect data during the peak of the defoliation event. Consequently, this project is being funded as a grant for rapid response research (RAPID).
Climate warming has resulted in longer growing seasons and milder winters in temperate forests, which should lead to more frequent outbreaks of insect defoliators. This project will provide important information on the consequences of such change to forest dynamics. This research will be conducted in the Manistee National Forest and has important implications to the management of this forest and similar forests in the temperate zone. The project will provide research training for a postdoctoral scholar and for graduate and undergraduate students. Local K-12 school teachers and students will also be engaged in the field research.
