"Rivers connect communities and are a major route of migration for people, animals, and plants. The green thread of vegetation along their banks connect not only riverine environments, but also serve as links into the interior. Discovering the diversity of plants surviving along Pittsburgh'sThree Rivers amidst factories, office buildings, parks, railroad tracks, and residences this summer has been a fascinating experience. Although invasive plants are present almost everywhere along the rivers, long stretches are dominated by native species that have been here for centuries."