Bear Lodge Project – Bull Hill Mine
January 2013
Weed Management Plan
10
Management Objective
: Containment
Integrated Management
Chemical: Dicamba + picloram, chlorsulfuron, and metsulfuron are all effective control
agents.
Biological: There are no known biocontrol agents approved for use.
Cultural: Increased competition from desirable plants is effective, proper management of
perennial grasses helps greatly.
Manual/Mechanical: Hand pulling can be successful on small populations; repeated frequent
tillage is also possible as a control method.
Hoary cress
Hoary cress is a perennial that grows erect up to 2 feet tall, and reproduces from both seeds and
roots. Leaves are alternate, lance shaped, grayish-green in color, and the base of upper leaves is
clasping the stem. Stems are stout and branching at the top. Flowers are small, white in color, with
four petals. There are numerous flower branches with dense flowers giving the plant a flat topped
appearance. Roots are extensive both horizontally and vertically, with shoots often coming up from
root stock. Seeds are reddish-brown in color, egg shaped, contained in heart shaped pods.
Management Objective
: Containment
Integrated Management
Chemical: 2,4-D, imazapic, chlorsulfuron, and metsulfuron are all effective control agents.
Biological: There are no known biocontrol agents approved for use.
Cultural: Increasing competition by desirable legumes, such as alfalfa, can reduce
populations.
Manual/Mechanical: Hand pulling can be effective if the roots are removed.
Houndstongue
Houndstongue is a biennial, reproducing by seed, with a rosette forming the first year and a
flowering stock elongating the second year. Leaves are velvety to the touch, basal leaves are broad
and lance shaped, while upper leaves are narrow and pointed, often clasping the stem. Flowers are
dark red, but can rarely be white, ¼ inch in diameter and grouped in terminal clusters. Roots consist
of a taproot and seeds consist of four flattened bur-like nutlets, with short barbed appendages.
Management Objective
: Containment
Integrated Management
Chemical: 2,4-D, netsulfuron, and imazapic are all effective control agents.
Biological: There are no known biocontrol agents approved for use.
Cultural: Increasing competition by desirable vegetation may reduce competitiveness.
Manual/Mechanical: Pulling and tilling can both be effective control measures.
