By Staff
KALAMAZOO - Garlic mustard is a serious threat to native plants, including some of our most beautiful wildflowers such as trillium, bloodroot and Dutchman's breeches.
That's why volunteers will be gathering at Dowagiac Woods from 8 to 11 a.m. Tuesday, April 19, to pull it.
Garlic mustard aggressively monopolizes light, moisture, nutrients, soil and space. It frequently occurs in moist, shaded soil and along roadsides and edges of woods,
particularly in disturbed areas. The current range of garlic mustard is
from eastern Canada, south to Virginia, and as far West as Nebraska.
Accurate identification is essential; the coarsely toothed leaves give off
an odor of garlic when crushed. The plant, a cool-season herb in the
mustard family, has a two-year life cycle. In the first year, the plants
appear as a rosette of green leaves close to the ground. The leaves remain
green through the winter, and in the second year develop into flowering
plants that are 2-3.5 feet tall that produce button-like clusters of small,
white flowers, each with four petals in the shape of a cross. In May, seeds
are produced in erect, slender four-sided pods. By late June, the plants
have died, but leave behind erect stalks of dry, pale brown seedpods that
may hold viable seed through the summer.
A single plant can produce thousands of seeds that can scatter several
yards from the parent plant. The seeds in the soil may be viable for five
years or more. The goal is to prevent seed production until the stored seed
is exhausted. For light infestations, hand removal of the plant is
possible. Because new plants can sprout from root fragments, it is
important to remove the plant with its entire root system by grasping the
base of the plant firmly and tugging slowly until the main root loosens
from the soil and the entire plant pulls out. This is most successful when
the plants are small and the soil is moist.
For larger infestations of garlic mustard, flowering stems can be cut at
ground level to prevent seed production. Once seedpods are present, the
stalks can be clipped, bagged, and removed from the site to help prevent
continued buildup of seed stores. This can be done through much of the summer.
For very heavy infestations, application of the systemic herbicide
glyphosate (e.g. Roundup) is also effective. Of course extreme care must be
taken not to get glyphosate on desirable plants, and the application must
strictly follow the package recommendations.
Regardless of the control method employed, annual monitoring is necessary
for a period of at least five years to ensure that seed stores of garlic
mustard have been exhausted. Your property will be more beautiful in the
future if you control this invasive weed now.
For further questions on garlic mustard and other horticultural issues,
please call the Emelee Rajzer, Consumer Horticulture Educator at MSU
Extension in Kalamazoo, (269) 383-8815 or email