Invasive Alien Plant Species of Virginia

Garlic Mustard (Alliaria petiolata (Bieb.) Cavara & Grande)

Description Garlic mustard is a biennial herb in the mustard family. Plants can range in height from 5 to 46 inches. The first year plants form rosettes of kidney- shaped leaves. In its second year, the plant grows a stem with leaves that are triangular and sharply toothed. The flowers are born in a cluster at the end of the stem, and each small flower has four white petals. Seeds are black, oblong and found in rows within a long narrow capsule called a silique. Crushed leaves and stems of this plant give off a distinctive garlic odor. bance created by periodic flooding. Habitat Prolific seed production and lack of Garlic mustard grows in rich, moist natural predators which might feed upland forests and wooded on garlic mustard allow it to quickly streambanks. It is shade tolerant and dominate the ground cover. Native readily invades disturbed areas such herbs in competition with garlic as roadsides and trail edges. Garlic mustard may suffer population de- mustard cannot tolerate acidic soils, clines. including undrained peat or muck. Control Distribution Light infestations of garlic mustard Native to Europe and Asia, garlic can be controlled by hand-pulling. mustard is now found in Canada, Plants should be pulled before seeds south to Virginia, and as far west as have ripened. Care must be taken to Kansas and Nebraska. It is believed insure the entire root is removed and to have been brought to North disturbance of the soil is minimal. America by European settlers for Severe infestations can be con- use in cooking and medicine. In Vir- trolled with herbicides. Garlic mus- ginia, garlic mustard is found tard is biennial. Its first year growth throughout the state, with notable overwinters as a basal rosette of kid- exceptions of southeastern and ney-shaped leaves, therefore it is northeastern counties. still green when many other herbs have died or gone into dormancy. Threats Foliar application of a glyphosate This species can invade a forest herbicide can be made in late fall to through a disturbance such as minimize damage to other plants. treefall or trail construction. Along Follow-up treatments may be nec- streambanks, the plant does excep- essary over two or three years to get Garlic Mustard (Alliaria petiolata) tionally well because of the distur- For more information, contact the Department of Conservation and Recreation or the Virginia Native Plant Society.

Virginia Native Plant Society P.O. Box 844, Annandale, VA 22030 1500 E. Main Street, Suite 312, Richmond, VA 23219 (804) 786-7951 Invasive Alien Plant Species of Vir ginia Garlic Mustard target plants that were missed as propriate concentrations, and the Commission. well as new sprouts. Glyphosate effective method and timing of their Fernald, M. 1950. Gray’s manual of botany. herbicides are recommended be- application. For more information 8th ed. American Book Co. New York. cause they are biodegradable, break- on herbicide use, contact a natural ing down into harmless components resource specialist or agricultural Harvill, A., et. al. 1992. Atlas of the Virginia on contact with soil. However, extension agent. Flora. Virginia Botanical Associates. glyphosate is a nonselective, sys- Burksville. temic herbicide and will affect all References Nuzzo, V. 1991. Experimental control of green vegetation. To be safe and ef- Kennay, J., G. Fell, and V. Nuzzo. 1990. garlic mustard in Northern Illinois using fective, herbicide use requires care- Garlic Mustard. Vegetation Management fire, herbicide and cutting. Natural Areas ful knowledge of the chemicals, ap- Guideline 1(10). Illinois Nature Preserves Journal 11(3):158-167.

For more information, contact the Department of Conservation and Recreation or the Virginia Native Plant Society.

Virginia Native Plant Society P.O. Box 844, Annandale, VA 22030 1500 E. Main Street, Suite 312, Richmond, VA 23219 (804) 786-7951