HPIPM:Common mullein

Taxonomy

Domain	Eukarya
Kingdom	Plantae
Phylum	Magnoliophyta
Class	Magnoliopsida
Superorder	Asteranae
Order	Lamiales
Family	Scrophulariaceae
Genus	Verbascum

Scientific Name

Verbascum thapsus

Common Name

common mullein

Common mullein (Verbascum thapsus)

Author: The Colorado Department of Natural Resources, Colorado State Parks, and Colorado Natural Areas Program - in partnership with the Division of Plant Industries in the Colorado Department of Agriculture.

Adapted from Appendix 4: Profiles of Colorado State-Listed Noxious Weeds, page 257 by Marjolein Schat, Montana State University

Identification and Life Cycle

Common mullein (Verbascum thapsus), also known as flannel leaf, fleawort, and Jacobs staff, is a biennial forb in the figwort family (Scrophulariaceae). Common mullein produces a basal rosette the first year and a single flowering stalk in the second year. The flowering stalk is stout, erect, and can reach up to 6 feet in height. The stem is longitudinally ridges by the bases of the leaves that continue down the stem beyond the point of attachment. The stem is densely wooly with branched hairs. Rosette leaves are covered with soft, fine hairs. Leaves on the flowering stalk are alternate, overlapping, light green, and densely wooly. Flowers are 1 inch in diameter, five lobed, and sulfur yellow in color. Flowers are grouped in a “corn cob”-shaped flowering raceme. Common mullein produces many seed pods, each containing many small cylindrical seeds. Seeds have numerous ridges and grooves.

Habitats

Common mullein prefers dry, gravely to sandy coarse textured soils. The plant commonly grows in pastures, meadows, waste areas, and along fencerows and river bottoms.

Impacts

Common mullein is not considered palatable to livestock due to its woolliness. Common mullein is not considered a serious agricultural weed since it can be controlled by cultivation. Common mullein can be a hard plant to control due to prolific seed production, in particular in disturbed sites. However, common mullein is easily outcompeted in areas with a densely vegetated ground cover. It is an ephemeral plant, which is eventually displaced by other plants in undisturbed sites.

Biology and Ecology

Common mullein reproduces by seed. Seeds germinate in early spring forming a rosette that continues to grow into late autumn and over winter. The following spring the plant produces a tall stem topped with a flowering raceme. Flowering and seed production occur from June to August. Individual plants can produce 100,000 to 180,000 seeds that can remain viable in the soil for 100 years.

Management Approaches

Integrated management should be aimed at preventing seed production and depleting the seed bank. A combination of herbicides or mechanical methods to remove rosettes and removal of seed heads from any plants that have bolted can control common mullein over time.

Biological Control

A weevil (Gymnaetron tetrum) has been introduced to North America and is capable of reducing seed production by 50%.

Mechanical and Cultural Control

Small stands can be hand pulled prior to seeding. Common mullein can be cut or mowed to prevent seed production, but stems must be cut below the root crown to avoid rebolting.

Chemical Control

A number of herbicides are available for control of common mullein.

Examples of herbicides that can be used to manage common mullein

Consult herbicide labels for additional rate, application, and safety information. Additional herbicide information can be found at http://www.greenbook.net.

Due to constantly changing labels, laws and regulations, the sponsors of this web site assume no liability for the suggested use of any chemicals noted in the management section. Contact your local pest management personnel for current information on labeled pesticides that can be used for the intended plant disease, insect pest or weed.

References

For more information and images please visit IPM Bugwood. http://www.ipmimages.org/search/action.cfm?q=common%20mullein&Start=1&results=77