Draba verna

Draba verna (syn. Erophila verna) may also go by the names spring draba, shadflower, nailwort, common whitlowgrass, vernal whitlow grass, early witlow grass or whitlow-grass. It is a small plant found in sagebrush country in the inland western United States, North Africa, temperate Asia, and most of Europe, including Britain. It was once thought to have been introduced to America from Europe, but is now considered native to both continents. It grows in very early spring. The flowers have four deeply notched white petals, and are borne an inch or two above the ground by a long stem. The leaves are clustered at the base.