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Common name: Sandburs
Scientific name: Cenchrus spinifex Cav. (field sandbur)
Cenchrus longispinus (Hack.) Fern (longspine sandbur)
Life Cycle: Annual
Origin: Americas
Poisonous: No
Sandbur is the common name for several annual grasses that produce burs with multiple sharp spines. These grasses grow in pastures, landscape beds, gardens, fields, and roadsides. Field sandbur and longspine sandbur are the two most common species. Southern sandbur is another species that is more narrowly distributed along southern states. All are native to the Americas.
Sandburs are particularly problematic at maturity. Because of their sharp burs, they inhibit grazing of desirable grasses; it is difficult for horses to selectively graze around the sandbur. Sandburs are a major weed of bermudagrass hay fields, in particular. Hay infested with sandburs also is undesirable because the burs inhibit hay consumption.
Sandburs are annual plants with a fibrous root system and depend on the burs for reproduction (fruit is encased in the bur). Sandburs are spread easily because the burs stick to domestic and wild animals. Though nontoxic, mechanical damage can occur if horses consume the burs.
Sandburs are not easily controlled without killing desirable forage grasses. However, small patches can be removed by hand. Mowing usually is ineffective for controlling or preventing bur formation. Consult your local Cooperative Extension Service personnel for herbicidal control in your area.
This information was provided by William W. Witt, PhD, a researcher in the department of Plant and Soil Science at the University of Kentucky.