Vernicia fordii

Tung oil tree

Nonnative to FloridaFISC Category 2 Invasive
Species Overview

Native to: Central and West China, Vietnam 

TOXIC PLANT- one seed can be fatal to humans, however all parts of the tung tree are poisonous even though it has been used to treat skin conditions and constipation. Symptoms may include severe stomach pain, vomiting, diarrhea, weakness, slowed breathing, and poor reflexes. The leaves give some people a poison-ivy-like rash. 

Tung oil trees are cultivated primarily for their seeds, but also used as ornamental trees in the landscape. The seeds produce oils that are used in the manufacture of lacquers, varnishes, paints, linoleum, oilcloth, resins, artificial leather, felt-base floor coverings, and greases, brake-linings and in clearing and polishing compounds. In its native range, the seedlings have been planted for thousands of years. During World War II, the Chinese used tung oil for motor fuel. 

Description
  • Family: Euphorbiaceae
  • Habit: trees are deciduous and can grow up to 40 feet tall having smooth bark and soft wood
  • Leaves: heart-shaped, sometimes lobed, alternate leaves are dark green and up to 6 inches wide. A distinguishing characteristic of tung oil tree are the presence of two red glands at the apices of the petiole.
  • Flowers: white with a rose colored center and are borne in clusters arising from terminal buds of shoots from the previous season. Tung oil tree flowers before it produces its leaves.
  • Fruit: spherical or pear-shaped, green to purple at maturity
  • Seeds: 4 to 5 seeds, hard outer shell and a kernel from which the oil is obtained
  • Distribution in Florida: central and north

 

Impacts

Tung oil tree invades forest edges, right-of-ways, and urban green spaces. Spread is accomplished mainly through seed production. Fruit production begins when trees are 2 to 4 years old. Vegetative reproduction occurs by way of suckers from underground stems. Tung oil tree is able to grow in a wide array of environmental conditions, making it a successful, but slow invasive.

Tung oil tree is considered a species of caution (requires management to prevent escape) in north Florida and not a problem in central and south Florida by the UF/IFAS Assessment. Tung oil tree is listed as a Category II invasive species on the FLEPPC list.

Management Plan


Management Options

The first step in preventative control of tung oil tree is to limit planting and removal of existing plants within the landscape. If possible, removal should occur before seeds are produced. Care must be exercised to prevent seed spread and dispersal during the removal process.

Cultural/Physical

Remove tung oil trees from the landscape and replace with native plants. 

Mechanical

Cut down larger trees. Hand pull seedlings before they mature. Remove all seeds from the area to prevent reinfestation.

Biological

Aphthona nigriscutis, a type of flea beetle, is a potential biological control agent for tung oil tree.

Chemical
  • Cut stump: 50% Garlon 3A within one minute of cutting. Retreatment may be necessary
  • Basal bark: 20% Garlon 4. Retreatment may be necessary
  • Incision point application: one hack for every 6 inches DBH, 100% Method, 0.5 mL per hack

 

Additional Resources


  1. Atlas of Florida Plants
  2. UF/IFAS Assessment of Nonnative Plants in Florida's Natural Areas
  3. USDA Natural Resources Conservation Service- Plants Database
  4. View the herbarium images from the University of Florida Herbarium Digital Imaging Projects