Recently Leonard and I came upon two wildflowers with “milk” in their common names. Milk kelloggia (Kelloggia galiodes) which I posted a week ago (Milk Kelloggia 07-17-17), is a native found throughout the western states. The other, Sierra milkwort (Polygala conrnuta), is native but endemic to California.
Also colloquially knows as Fish’s milkwort, P. cornuta formerly belonged to the genus Rhinotropis. This member of the Milkwort Family grows on rocky or gravelly slopes in chaparral or forest habitats mostly between 1,000 and 5,000 feet in elevation.
Sierra milkwort (“wort” means “plant”) is a perennial with many slender stems arising from rhizomes. The leaves are ovate to almost linear with minute hairs on the veins and fringing the leaf margin. There is a short petiole (stalk).
The Sierra milkwort inflorescence is a tight cluster of pediceled (with stalks) flowers at the terminal end of the stem. In the same cluster the flowers range from yellowish to greenish-white to plum or pink. Each flower has 5 sepals and 3 petals. The two outer sepals are winglike and surround a keeled central petal tipped with a short beak. The 8 stamens are fused at the base and envelop the superior ovary. The flowers are interesting in both their morphology and color variations.
Sierra milkwort fruits are flattened capsules, which become brownish when mature, and contain one or two seeds. I found it interesting how the flower surrounds the lenticular capsule as it forms (seen in the photograph titled “Winglike Lateral Sepals”).
The genus name, Polygala, comes from the Greek (poly = much, gala = milk). Some species in this genus were thought to increase the flow of milk. Cornuta, the species name, means “with horns” and most likely refers to the flower morphology.
Sierra milkwort grows in profusion along the trail around the base of Timbered Crater (Siskiyou County CA) where these specimens were photographed.