Chinese Tallow Tree: Invasive Species Control
Compiled by David Szpakowski
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| Management Techniques | |
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| Manual and Mechanical Control | Hand removal of trees is usually limited to trees less than three feet tall or to small infestations. Sawing down large trees will help to remove seed sources. Fruit should be removed from fallen trees in order to reduce the number of seeds present. In order to prevent resprouting, however, cut-stumps will require an herbicide application. Heavy equipment can be effectively used to control tallow trees on canal banks and in areas where soil disturbance and selective species removal are not important considerations. Stumps remaining following such treatment will require herbicide application to prevent regrowth from cut surfaces. In some agricultural areas, bulldozing and disking have been effective in the control of S. sebiferum (Bruce et al. 1997). Trees standing in water may be successfully killed by cutting them below the water line. |
| Grazing | Sheep and goats will eat the leaves of S. sebiferum, but toxicity to cattle limits their effectiveness as a control agent. Cattle will eat seedlings less than 6 cm tall (Bruce et al.1997). |
| Flooding | Flooding is not effective in controlling S. sebiferum, as it is adapted to flooding in fresh, brackish, and saltwater. |
| Prescribed Burning | The use of prescribed fire can be used to control S. sebiferum. Fire has various effects on tallow trees: (1) complete kill (preliminary data suggest that this is unlikely); (2) top-kill where the aerial portions of the trees are killed but resprouting occurs from the base, and (3) incomplete top-kill where the crown can resprout after fire. In areas with sufficient fuel, such as in prairies with good grass cover, summer burns killed or topkilled trees as tall as three meters. The control of trees growing in wet sites where fuels were poor, however, was much less effective. Burning during the dormant season (December), followed by burning or mowing during the growing season (July-August) seems to be the most effective. Additional experimental work is being done on the effect of fire on tallow trees (J.B. Grace, personal communication, Federal Wetlands Laboratory, USGS, Lafayette, LA). |
| Biological Control | There are currently no biocontrol agents identified for control of Chinese tallow. S. sebiferum trees are generally free of insect pests and serious pathogenic organisms. A few organisms known to associate with S. sebiferum (potential agents) include a bagworm, Eumeta sp., which feeds on the leaves, and the rootknot nematode Meloidogyne javanica. Fungi known to attack this tree include Cercospora stillingiae, Clitocybe tabescens, Dendrophthoe falcata, Phyllactina corylea, Phyllosticta stillingiae, and Phymatotrichum omnivorum (Duke 1983). Adult and juvenile leaf-footed bugs (Lepotglossus zonatus) have been observed feeding on fruits of S. sebiferum at Brazoria National Wildlife Refuge in Texas (Johnson and Allain 1998). |
| Herbicides | The most effective method for the control of S. sebiferum is the basal bark application of herbicide. Several organizations, including the Florida Department of Environmental Protection, the Florida Exotic Pest Plant Council, Florida Native Plant Society, the Florida Nature Conservancy, the Louisiana Nature Conservancy, and the Texas Nature Conservancy, have adopted this method of treatment (Jubinsky and Anderson, 1996; Randall and Meyers-Rice, unpublished). Effective treatment consists of spraying a band at least 15 cm wide around the lowest 30-60 cm of the trunks with triclopyr (brand names Garlon 3A, Garlon4, Pathfinder II and others) at a concentration of approximately 15%. Concentrations up to 20% might be required for larger trees. Vegetable oil and other similar products are effective surfactants. Basal bark applications may be ineffective on large trees with thick bark; for such trees a cut-stump method may be necessary. For a cutstump treatment, excellent results are reported with a 50% solution of the triclopyr formulation Garlon 3A or with a 10% solution of the herbicide imazapyr (brand names Arsenal, Chopper and others). Imazapyr is a soil-active herbicide that requires careful use when applied near desirable plants or trees to prevent it from killing them. Other herbicides that have successfully controlled S. sebiferum include the combined 2,4-D and picloram formulations (Grazon P+D and Grazon) applied to foliage, or hexazinone (Velpar L) applied to soil near plants (Bruce et al. 1997; Jubinsky and Anderson 1996). Frilling using glyphosate (Rodeo) is also an effective control method. Bergen (1998, pers. comm.) reports from Texas that the most effective time to apply herbicide to minimize seed spread is in late summer to early fall. |
Source: The Nature Conservancy ELEMENT STEWARDSHIP ABSTRACT for Sapium sebiferum Chinese tallow-tree, Florida aspen, popcorn tree Also see: Weed Control Methods Handbook: Tools and Techniques for Use in Natural Areas |
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| Herbicides Keep Out of Reach of Children |
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|---|---|---|---|
| Arsenal ** | Brochure |
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| Chopper ** | Brochure |
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| Garlon 3A * Water-based |
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| Garlon 4 * Oil-based |
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| Grazon P+D * Water-based |
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| Pathfinder II * Oil-based |
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| Remedy * Oil-based |
Brochure |
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| Rodeo * Water-based |
Brochure |
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| Tordon 22K * Water-based |
Brochure |
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| Velpar L *** | Brochure |
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| Herbicide Application Methods | |
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| Hack and Squirt (Frill Girdle) |
 Make a series of downward cuts, leaving the chip, and immediately apply herbicide into cuts.
It is best suited to trees at least 4 to 5 inches in diameter. Bark on larger trees is often too thick for most water soluble sprays to penetrate, so it is necessary to provide a direct pathway for herbicide entry into the plant's vascular system. Use a hatchet to make a series of downward cuts in the bark around the entire circumference of the tree trunk. For most species, it takes about one cut for every 2 inches of trunk diameter. Frill cuts are overlapping cuts in the tree bark around the stem. Immediately apply the selected herbicide into the cuts. Avoid application during heavy upward sap flow in the spring, when sap flowing out of the wound will prevent good absorption. Apply herbicides registered for this purpose undiluted or in dilution ratios from one-half to one-quarter strength. Read the product label to determine the appropriate dilution. Amine formulations of Garlon, Grazon, and 2,4-D are generally more effective than esters. Roundup undiluted or half-strength is excellent for hack and squirt applications. |
| Stem Injection |  Use special equipment to make injection applications. Injection cuts do not overlap as cut surface treatments do.
Specialized equipment is used to inject a specific amount into the tree at each injection point. Best results occur when injections are made every 2 to 6 inches around the tree. Trees or brush should be at least 1.5 inches in diameter at chest height. |
| Cut Stump |
Leave a tree stump 8 to 12 inches above the ground and cut the top of the stump level to allow uniform herbicide coverage. Thoroughly wet the cambium layer next to the bark so the conducting tissue carries the herbicide to the roots. On larger trees, treat only the outer 2 to 3 inches of the stump. The internal heartwood of the tree is already dead. On trees 3 inches or less in diameter, treat the entire cut surface. Moisture stress may affect control during the summer and early fall. Applications during the spring upward sap flow are not as successful as late spring and early summer treatments. Pathfinder, Garlon 4, Remedy, and Crossbow are good stump treatment products that mix readily with petroleum based penetrants. |
| Basal Bark |  Basal bark treatment involves the application of a herbicide to the lower 12 to 18 inches of the trunk or stem from early spring to mid-fall. Some species can be treated during the winter.
The selected herbicide is mixed with diesel fuel, kerosene, or other suitable carrier and applied until the bark is saturated. The low volatile ester formulations are the only oil soluble products registered for this use. This method is effective on trees of all sizes, but is most commonly used on small brush. |
| Thinline |  A thin stream of undiluted herbicide is sprayed horizontally, to all sides of a lower plant stem, to form a narrow band around each stem or clump. Specialized equipment calibrated to deliver small amounts of herbicide is needed to make such an application. |
| Foliar Spray |  Foliar treatment is a common method of treating brush up to 15 feet tall by hand.
Timing varies from early summer to late September, depending on the herbicide used. Foliar treatments are least effective during very hot weather and when trees are under drought stress. Herbicides such as 2,4-D, Banvel, Garlon, and Grazon can be applied in the early summer, while the herbicide Accord provides best results when applied in August or September. Arsenal applied from June through September provides best results. Adding a surfactant improves the performance of most foliar applied herbicides. Drift control additives are also available to reduce the number of fine droplets produced. DO NOT use diesel fuel as an additive when applying herbicides to foliage. Diesel fuel kills the leaves before the herbicide can be translocated by the plant. Spraying until runoff is not necessary. Spray to wet the leaves and keep moving. |
| Basal Soil |  Herbicides applied to the soil surface move into the root zone of the target plants with rainfall.
Commonly used soil-applied herbicides include Spike and Hyvar. Spike may be applied in narrow bands. Banding, also called braiding or lacing, involves the application of a concentrated herbicide solution to the soil in a line or narrow band spaced every 4 to 6 feet. This type of application is used to kill large numbers of trees as in the case of a fence row. Soil active herbicides may also be applied on a spot or individual tree basis with an exact delivery handgun applicator, known as a spotgun. |
Source: Alabama Cooperative Extension System ANR-1058, New Nov 1997. By John W. Everest, Extension Weed Scientist, Professor, and Mike Patterson, Extension Weed Scientist, Professor, both in Agronomy And Soils at Auburn University. |
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Stump spray treatment involves cutting down a tree and treating the freshly cut surface with a herbicide.