Flowers of astragalus douglasii
are creamy-white in color, while the buds are often pinkish. The largest petal, the banner, is about half an inch long and angled back at between 60 and 90 degrees. The keel petal is a little shorter, while the two wing petals are shorter still. The five-lobed calyx is light green, sparsely covered with short, dark, strigose hairs. Flowers form in vertical, elongated clusters of between 10 and 30, ascending to spreading. Fruits are inflated, thin-walled, light green pods up to 2 inches long and 1 inch wide.
Leaves are relatively numerous, and long, and plants produce many stems, forming sizeable clumps. Stems and leaves are covered by very short, strigose hairs. Leaflets are often notched at the tip, and the midvein is slightly recessed on the upper surface, and raised underneath.
There are three varieties (douglasii, perstrictus, parishii), distinguished by the shape of the calyx lobe, the hairiness of the calyx, and the stem position: erect or ascending to prostrate.