INVASIVE TREE PRESENTING PROBLEMS IN ALABAMA
A non-native tree in Alabama is causing problems in parts of the state.
|Photo courtesy of Charles T. Bryson, USDA Agricultural Research Service, Bugwood.org.|
The tungoil tree is an invasive plant species that is of growing concern to land managers in Alabama. It is found in the Lower Coastal Plain and southern parts of the Middle Coastal Plain regions of Alabama according to the Alabama Invasive Plant Council. Tungoil trees are found in localized and scattered populations in managed forests, natural areas and parks. Like all invasive species, the tungoil tree has the capability of altering native habitats to the detriment of wildlife.
The tungoil tree was reportedly first introduced to America in 1905 by the U.S. Department of Agriculture from Hankow, China. Tung oil has been used for centuries in China for waterproofing multiple items, and as an element of paint, varnish, linoleum and printer’s ink in the U.S.
The U.S. was the main importer of Chinese tung oil, especially during the late 1920s and early 1930s when imports exceeded 12 million gallons annually. During the 1920s and into the 1930s, several thousand acres of tungoil plantations were planted in some Gulf Coast states, and several tung oil mills were built to press the oil from the tung seed. Concerns about product security and the militarization of tung oil supplies prior to World War II led to price supports from the federal government that expanded the industry to more of the Gulf Coast. Late spring freezes in the 1950 and 1960s, competition from South American sources, and several major hurricanes along the Gulf Coast in the 1960s were all factors that led to the demise of the tung oil industry. Most producers cleared what tungoil trees were on their land and moved into other, more profitable agricultural products.
This rapidly-growing invasive tree forms dense stands and can produce viable seeds in as little as three years. These seeds are distributed by animals and water courses. Tungoil tree readily colonizes areas through stump sprouts. Tungoil has no known pests and the leaves and seeds are known to be poisonous. It is recommended that landowners remove this species from their property.
Control methods of tungoil tree and other invasive plants can be found in “A Management Guide for Invasive Plants in Southern Forests,” which is available in PDF format at www.srs.fs.usda.gov/pubs/36915.
The Alabama Department of Conservation and Natural Resources promotes wise stewardship, management and enjoyment of Alabama’s natural resources through five divisions: Marine Police, Marine Resources, State Lands, State Parks, and Wildlife and Freshwater Fisheries. To learn more about ADCNR visit www.outdooralabama.com.