Buffalobur

Solanum rostratum

Buffalobur

Family: Solanaceae

Other Common Names: Kansas thistle, Texas thistle
Weed class: C
Year Listed: 1988
Native to: Midwest region of the United States and Mexico
Is this Weed Toxic?:

livestock


Legal listings:

WA Quarantine list, WAC 16-750

Why Is It a Noxious Weed?

Buffalobur is generally considered a nuisance in its native range and is toxic to livestock. It is very aggressive in pastures and rangeland, competing with forage plants. Burs can get caught on sheep wool devaluing the wool.

How would I identify it?

General Description

This annual plant is spiny, hairy and around 1/2 to 3 feet tall. The entire plant, except the petals, is covered by straight yellow spines that are 1/8 to 1/2 inch long.

Flower Description

Flowers in clusters (racemes) of 3 to 15. Flowers are yellow, 5-lobed, flat and circular (rotate) and around 1 inch in diameter.

Leaf description

The leaves are alternate, 2 to 6 inches long, irregularly cut into 5 to 7 lobes, and extremely prickly.

Stem description

Upper stems are branching, upright, bushy, 1/2 to 3 feet long, and extremely prickly.

Fruit Seed Description

Fruit is a berry.

Where does it grow?

Buffalobur is found in fields, overgrazed pastures, yards, roadsides, waste areas, barn yards, and will grow in sandy soils, as well as dry hard soils to rich moist soils of cultivated fields. Please clickclick herehere to see a county level distribution map of buffalobur in Washington.

How Does it Reproduce?

Buffalobur reproduces by seed.

How Do I Control It?

Mechanical Control

Prevention of seed production is possible with repeated, close mowing or hoeing out plants before flower blossoms appear.

Cultural Control

.

Biological Control

.

Herbicide Control

Please refer to the PNW Weed Management Handbook, or contact your county noxious weed coordinator.

For More Information

See our Written Findings for more information about buffalobur (Solanum rostratum).

Lincoln County NWCB Brochure on buffalobur

Asotin County NWCB Fact Sheet on buffalobur

King County NWCB Fact Sheet on buffalobur

Clark County NWCB Fact Sheet on buffalobur

Stevens County NWCB Fact Sheet on buffalobur

Additional Photos