Astragalus preussii

 Astragalus preussii (common name - Preuss’ milkvetch) is an annual or perennial plant in the legume family (Fabaceae) found in the Colorado Plateau and Canyonlands region of the southwestern United States.
Description.
Growth pattern.
It is an annual or perennial plant from tall, growing upright from a woody base.
Leaves and stems.
It has compound pinnate leaves from long, with 7-25 , elliptic leaflets.
Inflorescence and fruit.
It blooms from March to June. The inflorescence has 3-22 flowers per stalk, with a small, green, 5-lobed calyx around a tubular set of white to pink to purple petals, long. 
When dried, seed pods are papery or leathery, elliptical, and are either smooth or covered with soft hairs.
Habitat and range.
It only grows in soils containing Selenium.
Ecological and human interactions.
It is named after Charles Preuss.