Botany
Weed of the Month
June, 2010: Sapium sebiferum (Triadica sebifera), the Chinese tallow tree or popcorn tree
Deliberately introduced as a crop plant and an ornamental, this tree has escaped cultivation and is aggressively invading natural areas throughout the Southeast.
Sapium sebiferum, the Chinese tallow tree or popcorn tree
Photograph courtesy of John Gwaltney, Southeastern Flora
Distinguishing Characteristics: The Chinese tallow grows to about 40 feet tall, with an airy, rounded crown. All parts of the plant exude a milky sap when damaged. The distinctive leaves are deciduous, alternate, with a slender petiole that is often as long as the blade. They are diamond-shaped, with a broad-tapering, almost truncated base, an abruptly long-pointed tip and an entire margin. The leaves are one to three inches long, and about 2/3 as broad. Separate male and female flowers are borne in long, slender, drooping yellow catkins. The fruit is a three-parted capsule which turns brown at maturity, splitting to reveal three white seeds. The seeds remain on the branches for a prolonged period of time and together they look like a popped kernel of popcorn.
Sapium sebiferum, the Chinese tallow tree or popcorn tree
Photograph courtesy of Walter Hodge, Atlas of Florida Vascular Plants
Distribution: The tree is native to Central China and Japan, but it is widely cultivated for the oil in its seeds. It has escaped and has become a weed in various parts of the world, but particularly in Asia and Australia. In the United States it is naturalized in the coastal states from North Carolina to Texas. It is still planted as a shade tree in California, but it has escaped sparingly there, perhaps because of the prevailingly dry climate.
Occurrence in Florida: The Chinese tallow tree is common in a variety of mostly moist habitats, from roadsides to mesic flatwoods and swamps. It has been recorded from 33 counties in all parts of the state.
Sapium sebiferum, the Chinese tallow tree or popcorn tree
Photograph courtesy of John Gwaltney, Southeastern Flora
Similar Species in Florida: The camphor tree (Cinnamomum camphora), another exotic invasive, could possibly be mistaken for the Chinese tallow tree, but its leaves are somewhat narrower, and they are 3-veined from the base; in addition, its fruit is a black drupe. The Indian rosewood (Dalbergia sissoo), an exotic ornamental that rarely escapes, has compound leaves, but its leaflets are very similar in shape to the leaves of the Chinese tallow tree. But again, the fruits easily distinguish the two, with those of the rosewood looking very much like the samaras of ash trees (Fraxinus spp.). Neither of these plants have a milky sap.
Means of Dispersal: Birds are attracted to the oily seeds of the Chinese tallow, and they disperse the seeds far from the parent tree. The plant also produces root suckers prolifically.
Sapium sebiferum, the Chinese tallow tree or popcorn tree
Photograph courtesy of John Gwaltney, Southeastern Flora
Comments: There is not general agreement as to the correct generic name for this plant (Triadica or Sapium ?), so we use the name as it appears in Rule 5B-57, Florida Administrative Code, where Sapium sebiferum is designated a noxious weed by the State of Florida. Louisiana, Mississippi and Texas have also designated it a noxious weed, but it has been a very useful plant in the past. The seeds produce two types of fat: a solid fat from the outer covering and a drying oil from the kernel. The fat has been used to make soap and candles, and the oil as a machine lubricant. The close-grained, white wood is favored by the Chinese for carving and furniture-making. It is also an attractive ornamental, and its leaves turn brilliant shades of red in the fall, even here in Florida where bright autumnal foliage color is a rarity. But because of its invasive tendencies, it should not be planted for any reason.
Further Information: Langeland, K.L., H.M. Cherry, C.M. McCormick and K.A. Craddock Burks. 2008. Nonnative plants in Florida’s natural areas. IFAS Communication Services, University of Florida, Gainesville. 193 pp.; http://www.floridata.com/ref/s/sapi_seb.cfm (Accessed: June 3, 2010); http://www.hort.purdue.edu/newcrop/duke_energy/sapium_sebiferum.html (Accessed: June 3, 2010)
Dr. Richard Weaver, Botanist
Florida Department of Agriculture and Consumer Services
Division of Plant Industry
1911 SW 34 Street
Gainesville, FL 32614
