March 1, 2012
What’s blooming? Red silk-cotton trees
Text and photos by Donald R. Hodel, Environmental Horticulture Advisor, University of California Cooperative ExtensionBombax ceiba, commonly known as the red silk-cotton tree, is a large, briefly deciduous tree occurring in warm monsoon forests in southern Asia. The Arboretum has the only two flowering specimens in the U. S. outside of Florida and Hawaii. The tree is famous for its large, showy, six-inch flowers with thick, waxy, red petals that densely clothe leafless branch tips in late winter and early spring. Widely planted and highly revered from India to southern China, it is unusually handsome and ornamental and has many uses. Known as the semal tree in India, a gummy secretion is obtained from the bark and sold as semal gum for medicinal use. The cottony fibers in the fruits are a substitute for kapok and used to stuff mattresses, pillows and cushions. The fleshy sepals of young flowers are cooked and eaten as a vegetable. The soft wood has been employed for matches and tea boxes while the fibrous inner bark makes suitable cordage. The tree is so highly revered that, according to Chinese historical records, the King of NamYuet, Chiu To, gave one to the emperor of the Han Dynasty in the 2nd century BC. The Arboretum’s two specimens put on their colorful, show-stopping display from February to April.