Mentzelia mollis is a species of flowering plant in the Loasaceae known by the common names soft blazingstar,[1]smooth blazingstar, and smooth stickleaf. It is native to the western United States, where it occurs in Idaho, Oregon, and Nevada.[2][3]
Description
This annual herb grows 5 to 12 centimeters tall with a thick, branching, erect stem. The leaves are lance-shaped and mostly smooth-edged. It produces flowers with bright yellow flowers with petals about a centimeter long and with many stamens in the middle. Flowering occurs in May and June.[2] The flowers are visited by bumblebees.[3] The fruit is a four-sided capsule about 2.5 centimeters long.[2]
This plant grows on deposits of montmorillonite, a slick, powdery clay soil. It also grows on volcanic ash soils high in potassium. The substrate is also high in calcium and sodium. Summer soil temperatures are hot.[3] The soils are mostly barren of vegetation but may host other annuals such as Monolepis pusilla, Mentzelia albicaulis, Cleomella macbrideana, and Phacelia humilis.[4] Only 10 to 12 inches of annual precipitation falls in the area.[3]