English ivy is an evergreen vine that is widely used as a landscaping groundcover. It creeps across the ground and it readily climbs trees, rock walls, and fences. The leaves are simple, smooth glossy green, and either 3-5 lobed or entire (the latter typical of flowering branches). The flowers are inconspicuous and presented in simple umbels (characteristic of the Araliaceae). Fruits are rather dry, black "berries," readily eaten and dispersed by birds.

Because it is aggressive, shade tolerant, and readily bird-dispersed, English ivy has become one of the most destuctive invasive plants in the Pacific Northwest forests. Many Washington and Oregon urban forests have nothing but ivy in their understory--a situation termed an "ivy desert." The thick layer of ivy leaves smothers native herbaceous plants and prevents seedling establishment of many native trees and shrubs. In addition, ivy readily climbs deciduous trees, increasing the weight and wind resistance of their canopies, making them more susceptible to blow-down. There is also some evidence that ivy harbors diseases that can attack our native species.