Coastal sandbur is an annual to short-lived perennial. The plant forms a loose tuft of culms (grass stems) similar to crabgrass. Each culm terminates with a raceme of spikelets, the flower clusters of grasses. In Cenchrus, each spikelet has two florets.

In most grasses, the florets are subtended by paper-thin bracts—usually two glumes, a lemma and a palea. In Cenchrus, the bracts are fused and modified into 8 or more spines. The spines are retrorsely (curved downward) barbed.

The spines may puncture the skin or even leather and the barbs act as insurance. The bur is held irritatingly fast until intentionally removed. Or the sandbur may merely attach to passing fur or clothes by the barbs and somehow, the spines work their way to the skin. The sandbur makes it a point of being a pain. Then one must gingerly remove the sandbur lest the spines puncture the fingertips. My choice? A needle-nose pliers.

Although, most sane creatures loathe an encounter with sandburs, there is one creature that, well, relishes the spiny fruits. I once observed a gopher tortoise chowing down on sandburs as if at a rare and exquisite feast.

 

(Compiled from: Guide to the Vascular Plants of Florida, Richard P. Wunderlin, University Press of Florida, Gainesville, 1998; Manual of Grasses, Hitchcock)