Wild Garlic
Allium canadense
Lily family (Liliaceae)

Description: This perennial plant consists of a rosette of basal leaves that are about 6-12" long and 2-3 mm. across. These erect to semi-erect leaves are linear, flat, and often slightly arching; they are medium green and glabrous. Each leaf has a poorly defined keel along its midvein, while its margins are smooth. Occasionally, flowering stalks emerge from the ground that are about the same height as the leaves, or slightly higher. These stalks are terete (round in cross-section), rather than flat, and they are held stiffly erect. Each stalk terminates in an inflorescence that has a sack-like covering spanning about " across. This sack-like covering is white-membranous and ovoid in shape, tapering into a long beak at its apex. This covering splits open and withers away to reveal an umbel of about 6-12 pedicellate flowers or a similar number of sessile bulblets (frequently some combination of both).

The star-shaped flowers are about " across. Each flower has 6 tepals, 6 stamens, and a light green ovary with a style. The tepals are lanceolate to elliptic in shape and white, light pink, or pink. The bulblets are about " long, ovoid in shape, and light green to pinkish red. Wild Garlic is especially likely to flower or have reddish bulblets in a sunny situation. The pedicels of the flowers are about " long, medium green, glabrous, and terete. The blooming period occurs during early summer and lasts about 3-4 weeks. There is no noticeable floral scent, although the foliage exudes a typical onion scent. After the blooming period, the flowers are replaced by seed capsules; each capsule contains several small dark seeds. The root system consists of a bulb with thick fibrous roots, from which offsets may occasionally develop. This plant can also reproduce by its seeds and/or aerial bulblets.

Cultivation: The preference is full sun or partial sun, moist to mesic conditions, and a fertile loam. This plant also grows in light shade in wooded areas, but it is less likely to flower (instead, only aerial bulblets are produced). While growth is best in a fertile loam, other kinds of soil are tolerated. Periods of dry weather are also tolerated. While Wild Garlic spreads readily by means of offsets and bulblets, it often fails to produce viable seeds. This is one of the first plants to develop leaves during the spring.

Range & Habitat: Wild Garlic occurs in every county of Illinois, where it is native and quite common. Habitats include moist to mesic black soil prairies, upland and floodplain woodlands, moist meadows near rivers and woodlands, thickets, banks of streams, thinly wooded bluffs, abandoned fields, pastures, areas along railroads, roadsides, and waste areas. Wild Garlic has low fidelity to any particular habitat; it is often observed in degraded prairies and woodlands. This plant doesn't compete well against taller forbs, such as Canada Goldenrod (Solidago canadensis), preferring areas with less ground cover.

Faunal Associations: The nectar and pollen of the flowers attract the Onion Bee (Heriades carinatum), mason bees (Hoplitis spp.), Stelid bees (Stelis spp.), Halictid bees (Lasioglossum spp.), plasterer bees (Colletes spp.), masked bees (Hylaeus spp.), Syrphid flies, bee flies (Bombylius spp.), and wasps. Other insects suck plant juices, feed on bulbs, and other parts of Wild Garlic and other Allium spp. These species include the Green Stink Bug (Acrosternum hilaris), the Onion Plant Bug (Lindbergocapsus allii), larvae of the False Japanese Beetle (Strigoderma arbicola), the Onion Maggot (Delia antiqua), larvae of the Black Onion Fly (Tritoxa flava), larvae of the Onion Bulb Fly (Eumerus strigatus), and Onion Thrips (Thrips tabaci). During the early spring when little else is green, the vernal basal leaves of Wild Garlic are occasionally browsed by White-tailed Deer (personal observation). Other hoofed mammalian herbivores, such as cattle, will consume Wild Garlic along with grass and other plants. This can cause the milk of such animals to have an off-flavor. Rabbits avoid consumption of this plant because they appear to dislike the onion scent and spicy taste of the foliage. The foliage and bulbs are edible to humans, although the consumption of large amounts may be slightly toxic.

Photographic Location: The photographs were taken at Red Bison Railroad Prairie in Savoy, Illinois.

Comments: This is the most common species of native onion (Allium sp.) in Illinois. Wild Garlic (Allium canadense) can be readily distinguished from other native onions, such as the Cliff Onion (Allium stellatum) and Nodding Onion (Allium cernuum), by the presence of aerial bulblets in its inflorescence. An introduced onion in Illinois, Field Garlic (Allium vineale), also produces such bulblets. However, the leaves of Field Garlic are elliptic in cross-section with a hollow interior (at least at their bases), while Wild Garlic has leaves that are flat and solid throughout. There is a variety of the Wild Garlic (Allium canadense var. mobilense) that produces only flowers, rather than bulblets and flowers, or only bulblets. However, it is less common than the typical variety, as shown in the photographs.