In this lab at the Tuskegee National Forest, we will examine the distribution of a plant parasite on its host species. The lab has two purposes. First, the lab introduces you to methods for analyzing the spatial distribution of organisms. Second, the lab should help you to gain insights into what factors may be influencing the distribution of an organism within its habitat.
Galls are growths on plants that are induced by parasitic organisms.
Galls are produced by some insects, mites, nematodes, bacteria, and fungi. Galls can be formed on any part of a plant, including roots, stems, fruits, and leaves. Thus, gall-makers are parasites of plants. The galls formed by insects and mites are particularly conspicuous and abundant. There are well over 1,000 species of gall-forming insects in North America.