Stillingia linearifolia is a species of flowering plant in the euphorb family known as queen's-root.
It is native to the Southwestern United States, Southern California, and Northwestern Mexico, where it occurs in several types of dry and disturbed habitat in deserts, mountains, foothills, and chaparral.[1] [2]
Stillingia linearifolia is a perennial herb producing a clump of slender, branching, erect stems approaching 70 centimeters in height. The alternately arranged leaves are linear and narrow, reaching 4 centimeters in length but less than 2 millimeters in width.
The inflorescence is an erect spike of flowers a few centimeters long. The plant is monoecious, and each spike has several male flowers at the tip and a few fruit-bearing female flowers below these. Neither type of flower has petals. The ovary of the female flower develops into a three-lobed greenish capsule 3 to 4 millimeters wide.
There is a tiny black seed in each of the three chambers of the fruit.