About Lygodesmia exigua (A.Gray) A.Gray
Prenanthella is a monotypic genus of flowering plants in the daisy family, Asteraceae. This genus contains only one species: Prenanthella exigua, which has the common name brightwhite, and is also known scientifically as Lygodesmia exigua (A.Gray) A.Gray. This species is native to the southwestern United States, ranging from California to Texas, and has been found as far north as Idaho. It grows in habitats including desert and woodlands. This annual herb grows a slender, branching stem that reaches a maximum height near 40 centimeters. The plant has a sparse coating of glandular hairs and contains milky juice. Most leaves grow near the base of the stem; these leaves are broadly lance-shaped and sometimes divided into segments. Smaller leaves grow higher on the stem, and these may be reduced to scale-like structures, leaving most of the stem bare. The inflorescence is a wide open panicle holding several flower heads. Each small head is cylindrical and narrow, with its base wrapped in lance-shaped phyllaries. At the tip of the head, 3 to 4 ray florets bloom; this species does not produce any disc florets. Each floret is white to pale pink and has a toothed tip. The fruit is a white achene topped with a pappus of white bristles.
