About Astragalus arenarius L.
Astragalus arenarius L. is a somewhat recumbent plant that produces slender branched stems measuring 10 to 40 cm in length, and typically grows to 30 cm tall. It can be told apart from related species by several key features: leaflets arranged in 2 to 6 pairs, measuring 2 to 4 mm wide and 10 to 20 mm long; calyces that mostly have strongly asymmetric bifurcate hairs; a standard (the large posterior petal found in legume flowers) 15 to 17 mm long; and legumes 12 to 20 mm long. Its petals vary in color from light purple to lilac, and are rarely white. It flowers from June to July. As its specific name suggests, A. arenarius grows in sandy or gravelly areas in locations with little competition from grasses, including sandy open pine woodlands, dunes, river banks, roadsides, and railway embankments. The larvae of the moth species Coleophora gallipennella, C. onobrychiella, C. polonicella, and Syncopacma albifrontella feed on this plant.