Pronounced (approximate): so-LAY-num ros-TRAY-tum
A prickly annual with yellow flowers and deeply lobed leaves.
Buffalo Bur (Solanum rostratum): field photograph. Tap the photo to open the gallery.
Family Solanaceae
Life cycle Annual
Blooms Summer–early fall
Height 1 to 3 feet
Habitat Dry disturbed ground, fields, roadsides and open prairie
Common names: Buffalo Bur · Buffalobur · Buffalo-bur Nightshade
Bloom timing varies with latitude, weather and local conditions.
Explore reported observations. Sightings are not a complete range map.
Dry disturbed ground, fields, roadsides and open prairie. Flowering season: Summer–early fall.
Horse Nettle usually has white or pale violet flowers and exposed yellow berries. Buffalo Bur has yellow flowers and fruits enclosed by a prickly calyx.
Yellow five-lobed flowers have a conspicuous projecting anther.
Leaves have rounded lobes; stems and leaf veins carry sharp prickles.
The prickly calyx enlarges around the developing fruit. Pair close views with a photograph of the whole plant.
8 field photographs. Select a photograph to enlarge it; use Load more photos to see the rest.
Native to parts of the central and southern United States and Mexico; introduced farther north and east, including Illinois and Wisconsin.
Reported U.S. distribution
AL, AK, AZ, AR, CA, CO, CT, DE, DC, FL, GA, ID, IL, IN, IA, KS, KY, LA, ME, MD, MA, MI, MN, MS, MO, MT, NE, NV, NH, NJ, NM, NY, NC, ND, OH, OK, OR, PA, RI, SC, SD, TN, TX, UT, VT, VA, WA, WV, WI, WY
Includes native and introduced state records where listed; a state record does not imply occurrence in every county.
Observation maps show submitted records, not every place the plant occurs. Follow local access rules when visiting a site.
Practice recognizing Buffalo Bur in the flower quiz, or compare it with other plants in the guide.
Field photographs: Where’s Wildlife.