Burclover is a very common lawn weed in Southern California.  To keep a lawn free of it is a constant job.  Seed of burclover brought in, often from a considerable distance.

The leaves have three leaflets, and at first glance look like clover.  The flowers are bright yellow, but tiny. They are shaped like pea flowers.  The stipules (leaf-like things where the leaf joins the main stem) have a characteristic toothy appearance, by which the species can be identified even when no fruit are present.

The fruit is a pod coiled into a helix, with the overall shape of a sphere.  The outer edge of the pod has sharp, hooked spines.  As the fruit dries out the spines harden.  They hook into clothing, tangle into fur and carpets.  They are very hard on bare feet.

The roots of burclover, like other members of the family Fabaceae, have nodules on their roots.  These lumps house nitrogen fixing bacteria, Sinorhizobium medicae.

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