Arum family (Araceae)
Description: This native perennial plant is 1½–2½' tall. It consists of a single basal leaf and single flowering stalk. The basal leaf has a long stout petiole that is up to 2' long and erect. This petiole is pale green, glabrous, and glaucous. The basal leaf is up to 2½' long and 2' across; it divides into 5-13 leaflets that are parallel with the ground. Each leaflet is up to 8" long and 2½" across, narrowly ovate, smooth along the margins, glabrous, and dark green. The 2 terminal leaflets may be deeply cleft into 2 or 3 lobes that resemble smaller leaflets. The naked flowering stalk is about ½–1' tall (not including the flower); it is whitish green, unbranched, erect, and hairless. At the apex of this stalk is a single flower that consists of a spathe and spadix. The spathe is about 2" long, pale green, glabrous, and glaucous. This spathe wraps around the base of the spadix, but it is partially open and pointed at the top. The spadix is about 6-12" long. The lower portion of the spadix is about 2" long and nearly surrounded by the spathe; it is cylindrical in shape and bears the male and/or female flowers. Most plants are monoecious with separate male and female flowers, but sometimes they are unisexual. The male flowers occur above the female flowers; they are both rather small and inconspicuous. The upper portion of the spadix is about 4-10" long and tapers gradually to a point. It is usually whitish green and remains more or less erect. The blooming period occurs during late spring and early summer and the flowers remain attractive for about a month. They may release a fungus-like scent that is not detectable by the human nose. Each flower is replaced by an ovoid mass of berries, which become orange-red by the end of the summer. The root system consists of a corm with secondary roots. This plant can spread by forming offsets or by reseeding itself.
Cultivation: The preference is dappled sunlight during the spring and light shade during the summer. The soil should be moist and loamy with a layer of decaying leaves. This plant adapts to shady areas underneath trees and doesn't like to dry out. It has few problems with disease and insect pests.
Range & Habitat: Green Dragon occurs occasionally throughout most of Illinois, although it is uncommon or absent in the NW area of the state (see Distribution Map). Habitats include moist deciduous woodlands, shady seeps, and wooded areas adjacent to springs and vernal pools. The presence of this species is an indication that the original woodland flora is still intact. Green Dragon often occurs in the same habitats as the closely related Arisaema triphyllum (Jack-in-the-Pulpit), but the latter species is the more common of the two.
Faunal Associations: The flowers of Green Dragon attract simple flies (Nematocera), particularly fungus gnats. A thrip species, Ctenothrips bridwelli, has been observed feeding on Green Dragon in Illinois. The berries are eaten by the Wild Turkey, Wood Thrush, and possibly other woodland birds. Mammalian herbivores, including White-Tailed Deer, rarely feed on the foliage and corms as they are highly toxic. The toxic agent is calcium oxalate, which causes a burning sensation in the mouth, gastrointestinal distress, and possible damage to the kidneys.
Photographic Location: Near a vernal pool at Busey Woods in Urbana, Illinois.
Comments: Green Dragon is an attractive foliage plant for shady places and the unusual flowers are interesting as well. This species resembles Arisaema triphyllum (Jack-in-the-Pulpit) somewhat, but the latter has only 3 leaflets per compound leaf. There are also differences in the structure of their flowers: the spadix of Green Dragon is much longer and strongly exerted from the spathe, while the spathe of Jack-in-the-Pulpit forms a hood over the spadix.