The Enemy: Moth mullein (Verbascum blatteria L.)

Strategy: This biennial plant grows in disturbed areas with compact soils. Its leaves are mostly hairless with long, narrow, heavily serrated margins. It sends up a long, pointed yellow-flowered seed-head and each flower has a distinct stem (unlike common mullein) and forms a round fruit. It can grow up to 8 feet tall but is typically only 4 to 5 feet tall. Since it is a biennial, the first year rosettes are darker green and it spreads to about 2 feet in diameter. It is rigid and can be seen sticking up through the winter snow and above the other plants the following spring.

Attack: Since this plant likes open soils in disturbed areas, it can be found anywhere, even in hoofmarks made by animals. It is troublesome in that it gets fairly thick, is undesirable for grazing and competes for moisture and nutrients with desirable species.

Defense: Mechanical control is effective, as with most biennials. Just ensure that you remove a few inches of the root below the surface. Disking and plowing are not very effective, as this plant generally shows up on steep, south-facing slopes. Although there has not been much biological insect research performed on this plant, there a few native insects found in the flowers eating their way through the seeds. Herbicides such as Escort XP, Telar XP and Opensight are effective, but the secret is to add a quality surfactant to get the herbicide into the plants cuticle where it can do some good. Proper identification is key so consult with your weed professional to manage this weed.

To learn more, call Bonneville County Weed Superintendent Jeffrey Pettingill at 208-529-1397 or email