Wild Asparagus
Asparagus officinalis
Lily family (Liliaceae)

Description: This introduced perennial plant is 2-7' tall. It branches occasionally and has a spindly-ferny appearance. The central stem at the base of the plant is stout and more or less round in circumference. Appressed against this stem are small alternate leaves that are scale-like and deltoid in shape. When the central stem is about 6" tall, it resembles the spears of asparagus that are sold in supermarkets. As this stem continues to lengthen, it develops alternate branches that are more narrow in circumference. Each of these branches develops whorls of filiform branchlets where the tiny scale-like leaves occur. Each branchlet is up to 1" long. The foliage of Wild Asparagus is glabrous.

At the base of the whorled branchlets, there develops 1 or 2 flowers from nodding hairless stalks up to 1" long. Because Wild Asparagus is dioecious, a single plant will produce either all male flowers or all female flowers. Both types of flower are about 1/3" long and have 6 oblong tepals that are greenish white or greenish yellow. The male flowers have 6 stamens with yellow anthers, while the female flowers have a pistil with a single style. The tepals of the male flowers curve outward at their tips, resembling a little bell, while the female flowers are more cylindrical. The blooming period occurs during the late spring to early summer and lasts about 1 month. Each female flower is replaced by a single fleshy berry about 1/3" across. This berry is spheroid and glabrous, containing several seeds inside. It is initially green, but turns red when fully ripened. At the apex of the berry are remnants of the tepals. The root system produces rhizomes that are long and spreading. This plant often forms vegetative colonies.

Cultivation: The preference is full sun and moist to slightly dry conditions. This plant grows readily in soil that contains loam, sand, or gravelly material; it forms vegetative colonies more readily in soil that is sandy or slightly gritty. Wild Asparagus appears to have fewer problems with disease than some cultivated varieties. It can spread aggressively in some situations and appears to resist the herbicides that are applied along railroad tracks.

Range & Habitat: Wild Asparagus is a common plant that occurs in most counties of Illinois (see Distribution Map). Official records probably underestimate its distribution. Habitats include mesic black soil prairies, grassy meadows, thickets, fence rows, areas underneath utility lines, abandoned fields, vacant lots, areas along railroads and roadsides, and waste areas. The preference is disturbed areas, although it can invade high quality natural areas to some extent. Asparagus has been cultivated as a vegetable since antiquity and is native to Eurasia. It is still popular as a vegetable today.

Faunal Associations: According to Müller of 19th century Germany, the nectar and pollen of the flowers attract small to medium-sized bees, including honeybees, Mason bees, Masked bees (Hylaeus spp.), Halictid bees, and Large Leaf-Cutting bees (Megachile centuncularis, which also occurs in North America). The red berries are eaten by birds, which helps to distribute the seeds far and wide. While the young shoots are tender and edible, they become stringy and tough with maturity. Cattle have reportedly been poisoned from the consumption of mature plants.

Photographic Location: Along a railroad in Champaign, Illinois.

Comments: Wild Asparagus is an odd-looking plant of the Lily family with insignificant scale-like leaves. Its fern-like appearance is the result of the whorled filiform branchlets, which are not true leaves. Although the flowers are produced in abundance on healthy plants, they are not very showy. While most dioecious plants in Illinois are wind-pollinated, Wild Asparagus is an exception because it is insect-pollinated.