Deciduous leaf litter is often a primary source of energy at the base of the food web in seasonal woodland ponds (e.g., vernal or autumnal pools), which are common in the northeastern United States. It is therefore important to understand how leaf diet affects growth of detritivores, such as the caddisfly Limnephilus indivisus Walker, that feed almost exclusively on submerged plant matter in seasonal pond systems. Growth may relate to how rapidly a caddisfly is able to complete its larval development and pupate, and hence its ability to survive in small ponds with short hydroperiods. Growth is also related to the maximum size the larva achieves. In many organisms, attaining a larger size conveys several distinct advantages: larger individuals typically have higher survival rates and increased fecundity, and hence greater fitness compared to smaller conspecifics or competing sympatric species. To assess how leaf diet influences the growth of larvae of L. indivisus, we conducted a controlled experiment to test how different leaf diets influenced larval growth. The leaf diet experiment was set up as follows: Treatment 1: Acer rubrum (Red Maple), Treatment 2: Quercus spp. (oak), and Treatment 3: Red Maple and oak. L. indivisus that were fed oak leaves or a mix of oak and Red Maple leaves grew significantly larger than larvae fed Red Maple leaves only. In Treatment 3, the caddisfly was observed more frequently on the oak leaf compared to the Red Maple leaf. Although L. indivisus selected oak leaves more often during the experiment, oak leaves were less abundant than maple leaves at our study site. We hypothesize that the oak leaves provide more nutrients to L. indivisus due to a combination of physical, biological, and chemical properties which results in more larval growth.