Also known as: hedge garlic, sauce-alone, jack-by-the-hedge, poor man’s mustard, jack-in-the-bush, garlic root, garlicwort, and mustard root.
Garlic mustard is one of our region’s most notorious invasive weeds. A single plant of can produce numerous seeds that can survive in soil for many years, allowing it to quickly take over an area. It also changes the composition of local soils making it inhospitable for other plants. If you’ve spotted garlic mustard in the watershed, do not hesitate to take action!
Description:
| Life Cycle: | Biennial (life cycle lasts two years) |
| Early Detection and Rapid Response species: | Yes |
| Height: | Averages 3 feet (1 meter) |
| Leaf Description: | During its first year, the plant forms a rosette with kidney-shaped, dark green leaves. During its second year, it produces triangular-shaped, serrated Having a jagged edge. leaves. New leaves have a strong garlic odor. |
| Fruit & Flower Description: | Flowers have four small, white petals in the shape of a cross. Each plant can produce up to 5,000 seeds that can remain viable in the soil for ten or more years. |
| Bloom Time: | April to June during the plant’s second year. |
Habitat:
- Produces dense stands in riparian areasAreas that are directly adjacent to flowing streams, creeks, or rivers. and forest understories including, urban parks, woodlands, roadsides, trails, streambanks, and floodplains.
Impact:
- Monopolizes light, nutrients, soil, and space and to quickly displaces native plants, reducing wildlife habitat.
- Once established, emits chemicals from its roots that prevent other plants from growing nearby. This creates an environment that only it can grow in.
What we’re doing about it:
- Garlic mustard is categorized as a priority species for the Tualatin SWCD. Over the last decade, partners across the Tualatin River watershed have made tremendous strides in controlling it. Although we have made progress, there is still a long way to go.
- If identified within Washington County, a specially trained crew can come out and survey for garlic mustard. If found, the crew will treat the infestation at no cost to you.
What you can do about it:
- The best thing you can do to slow the spread of garlic mustard is to report it to the Oregon Invasives Species Hotline.
- Mowing is not a reliable treatment, as plants will re-grow and produce seeds later in the season.
- Small patches can be pulled by hand, making sure to remove the entire root system and throwing away the plant in a plastic bag in the trash— not your yard waste bin or home compost.
Look-alikes:
Garlic mustard is often confused with another invasive ground cover, creeping Charlie (Glechoma hederacea). Creeping Charlie does not grow as a rosette and grows as a vine that crawls along the ground.
Fringecup (Tellima grandiflora), a native perennial groundcover, is frequently confused with garlic mustard. Fringecup occupies the same habitats as garlic mustard (shaded streams and forest understories) and its leaves and low-growing stature resemble garlic mustard. The best way to tell these two species apart is by examining their flowers, Fringecup’s flowers are bell-shaped with five petals.
Piggyback plant (Tolmiea menziesii) is another native look-alike of garlic mustard. Piggyback plant also thrives in shaded streams and forest understories. It resembles fringecup but has purplish-brown flowers.
Noxious Weed Listing:
| State of Oregon: | Class B |
| State of Washington: | Class A |
More Resources:
Download Garlic Mustard Best Management Practices factsheet
- Pacific Northwest Weed Management Handbook: Garlic mustard
- University of California, Weed Research & Information Center: Garlic mustard