Knawel is usually a winter annual but occasionally a summer annual. The species has a taproot and a fibrous root system. Cotyledons are linear in outline and less than 1 mm wide with a sharp tip. Stems grow prostrate along the ground, are branched and form dense mats outward from a central plant. Flowers are inconspicuous, green in color, and somewhat spiny. Flowers also occur in clusters that arise from the position between the leaf bases and the stem. Knawel's identifying characteristics include small, linear leaves and a lack of hair on the leaves and stems.
