War on Weeds—weeds are everybody’s problem

THE ISSUE:   Buffalobur

Buffalobur (Solanum rostratum) is an prickly annual weed, native to Mexico and the great plains of the U.S. Seeds are easily transported by wind, water, humans, livestock, and wildlife. It invades rights-of-way, disturbed sites, fallow agricultural land, and dry stream beds. 

 Buffalobur can grow up to 2 feet tall and is drought tolerant allowing it to grow in a variety of conditions. It has dark green leaves that are deeply lobed and covered in short hairs. Stems, leaves and seed pods are covered with yellow spines. Flowers are bright yellow, have five petals, and are approximately 1 inch in diameter. Seeds are produced inside of a berry that is inside of a bur-like structure known as a calyx. Once the fruit is mature the berries split, and flat black seeds fall out. As the plant matures the main stem will break, allowing this weed to tumble along the ground as the wind blows. Each plant can produce up to 8,500 seeds. 

Integrated Pest Management (IPM) Options: 

• Prevention— Learn to identify this plant. Always clean equipment and clothing after leaving invested areas. 

• Mechanical— Small infestations can easily be removed by hand or hoeing. Protective clothing should be worn as the spines are sharp. Repeated mowing can also be an effective form of control. 

• Cultural- buffalobur is not extremely competitive so establishing a healthy stand of beneficial vegetation that will compete with weed seedlings can be very effective. It is critical that buffalobur is controlled prior to the production of blossoms. 

• Chemical—Applying herbicides prior to flowering provides the best control. For specific herbicide active ingredient recommendations visit: https://pnwhandbooks.org/ . Search “buffalobur” in the weed section.  Always read and follow herbicide label directions!

Justin Hatch, University of Idaho Extension Agriculture Educator in Caribou County. 208-547-3205
[email protected]@uidaho.edu