BUFFALO BUR
File Size: 59 KB
 
Solanum rostratum  Dunal
Tallgrass Prairie National Preserve, Chase County, Kansas
Annual
Height: 8-28 inches
Family: Solanaceae - Nightshade Family
Flowering Period:   May, June, July, August, September
Also Called: Kansas thistle.
Stems: Erect, single, much-branched, covered with tiny star-shaped hairs, armed with yellow spines.
Leaves: Alternate, stalked, egg-shaped to broadly elliptic in outline, 1-2 times pinnately lobed or cleft, 1.5 to 6 inches long, 1 to 4 inches wide; lobes irregular, spiny, star-shaped hairy; tips rounded.
Inflorescences: Racemes, 5-15-flowered, short-stalked, near ends of branches.
Flowers: 3/4 to 1 inch wide; calyces 5-lobed, very spiny; corollas somewhat flattened, 5-lobed, bright yellow; stamens 5, curving forward and down; anthers 4 yellow, alike, 1 purplish, enlarged, longer.
Fruits: Berries, spherical, to 2/5 inch in diameter, enclosed by spiny calyx; seeds numerous, egg- to kidney-shaped, pitted, dark.
Habitat: Disturbed sites, overgrazed pastures, waste areas, feedlots, and roadsides.
Distribution: Throughout Kansas.
Comments: The common name "buffalo bur" alludes to the plant's tendency to grow abundantly around bison wallows. Buffalo bur is drought resistant and extremely aggressive. It often thrives in actively-used cattle corrals. When mature, the main stem breaks near the ground and the plant rolls like a tumbleweed, scattering thousands of seeds.

Buffalo bur
122 KB
Riley County, Kansas
Buffalo bur berries enclosed in spiny calyces
92 KB
Konza Prairie, Riley County, Kansas
Buffalo bur
108 KB
Konza Prairie, Riley County, Kansas
Buffalo bur
105 KB
Konza Prairie, Riley County, Kansas
Buffalo bur spiny calyces
147 KB
Konza Prairie, Riley County, Kansas