The Chinese Tallow (Popcorn) Tree
An Ornamental Beauty
The tallow-tree or popcorn-tree, a native of eastern Asia (the same latitudes as the Southeastern U.S.), has long been a popular landscaping choice in this region for its brilliant fall color, distinctive seed capsules, and easy care as a landscape ornamental. It has been used extensively throughout North and Central Florida encompassing approximately 38 of Florida's 67 counties.
So What's The Problem
Unfortunately, the Chinese tallow didn't stay in the areas where it was planted. Of the 38 counties where it as planted as a landscape ornamental, it can be found in natural areas of these counties. This is primarily due to seeds that are readily eaten and dispersed by birds. They also float and can be carried easily by rivers, streams, and stormwater runoff to new destinations. Next time you're in one of Florida's state parks or recreation areas in the northern and central part of the state, ask the park personnel if they have experienced problems with Chinese tallow; you can bet the answer will be YES!
Some exotic plants, like Chinese tallow, have escaped cultivation and disrupted native ecosystems. They are referred to as "invasive" exotic plants. Invasive exotic plants all share several common characteristics: they grow quickly, propagate easily, resist native pests, grow in a wide range of soils, can invade undisturbed habitats, and have traits considered attractive enough to encourage the further distribution by people. It is important to remember that not all exotic plants are invasive.
How Can It Be Controlled
An environmentally sound practice for Florida landowners should be to NOT purchase or distribute Chinese tallow-trees or seeds (as well as other invasive exotics). Florida residents with Chinese tallow are encouraged to remove them. Please take the time to revisit the sites to pull up seedlings as they germinate.
The control of invasive exotic vegetation can be accomplished by utilizing biological control agents (insects and pathogens), herbicides, mechanical manipulation, or combinations of these methods, (integrated pest =management). The Department of Environmental Protection, in cooperation with the Florida Exotic Pest Plant Council, The Nature Conservancy, and a consortium of resource managers from numerous southeastern states, are committed to evaluating all management options to determine which approach is the most environmentally compatible and cost effective for long term maintenance control of Chinese tallow.
Attempts at managing Chinese tallow suggest that herbicidal methods are the most effective option for control at this time. Tests of simply cutting down tallow trees resulted in extensive root and stump sprouting. Biological control is being pursued, but requires lengthy field research in the native range of Chinese tallow to find insects, or pathogens, that are host-specific.
While plants are actively growing, excellent control is being achieved in terrestrial sites with the use of Triclopyer (Garlon 4) and a mineral or vegetable oil adjuvant, designed for basal applications. Note: Triclopyer is labeled for terrestrial applications only.
Numerous herbicide application methods are recognized for the control of woody plants. Those most suitable for the control of tallow include the following:
- Basal Bark Application - Basal bark applications are made by applying herbicide directly to the bark around the circumference of the tree up to 15 inches (38 cm.) above the ground. Thorough wetting of the indicated area is necessary for good control. Hand-held equipment (paintbrush), or backpack sprayers, are usually used for the application. Trees that have stems less than 6 inches in basal diameter, apply up to a 5% Triclopyr solution mixed with spray adjuvant oil. Trees exceeding 6 inches in basal diameter can be successfully controlled with a 15-20% Triclopyr/oil solution. Old or rough bark requires more spray than smooth young bark.
- Cut Stump Treatment - To control resprouting of freshly cut stumps, a 20% solution of Triclopyr will provide control. Spray the root collar area, sides of the stump, and the outer portion of the cut surface including the cambium until thoroughly wet, but not to the point of runoff. No more than 1/2 hour should elapse between cutting and applying herbicide.
The best time to initiate herbicidal control measures on Chinese tallow is during the spring months - the trees are breaking dormancy and the sap is rising. Also, there are no seeds being produced. During this time, either the Cut Stump or Basal Bark treatment are effective. During a normal weather year, trees begin producing seed in late August or early September. Please do not attempt to utilize the Cut Stump treatment during periods of the year when the seeds, or 'popcorn' fruits are present on the tree. By felling trees during these periods, the chance of spreading viable seed increase dramatically! During autumn months, restrict control measures to the Basal Bark method only.