Southern Research Station
United States Department of Agriculture
200 Weaver Boulevard
P.O. Box 2680
Asheville, NC 28802
May 29, 2003

Science Contact: Dr. James H. Miller
News Release Contact: ZoŽ Hoyle

SRS Publishes Guide for Identifying and Controlling Nonnative Invasive Plants

The USDA Forest Service Southern Research Station (SRS) has published a new guide for identifying and controlling nonnative invasive plants in Southern forests. Written by Dr. James H. Miller, research ecologist at the SRS Forest Vegetation Management unit in Auburn, AL, Nonnative Invasive Plants of the Southern Forests provides an important new resource for individuals and agencies trying to control the spread of these plants.

Nonnative invasive plants infest millions of acres of public and private forest land in the Southeast U.S, destroying native plant communities, stopping productivity and limiting diversity. Largely unnoticed by the general public, these plants are steadily moving deeper into the forest along corridors formed by roads, trails, streams, and rivers. Integrated pest management programs that use safe and effective control treatments are urgently needed to stem the spread and reclaim forest habitats.

"Effectively controlling nonnative invasive plants relies on the constant surveillance of the road and stream sides they spread along," said Miller. "Eradicating these plants is much easier when they first appear, so it is important to be able to identify them in both growing and dormant seasons."

Miller's book covers 33 plant groups, with over 40 species highlighted. The identification section of the guide includes a complete description of each plant, its ecology, resemblances to other plants, history, and use. Detailed photographs illustrate how the plant looks in different seasons of the year, including flowers, fruits, stems, and overall shape.

Whether they were introduced accidentally or brought in for livestock forage or ornamental use, these plants have left an environment where they are kept in check by insects or disease, and compete unfairly with the native vegetation. "Southern forests are literally choked by kudzu, cogongrass, oriental bittersweet, and privet," said Miller. "While most people are aware of these first invaders, many do not realize the problems that ornamental plants such as periwinkle, burning bush, and English ivy cause. Most nonnative invasive plants are perennials and form extensive roots and runners. They take over quickly and can be difficult to remove."

Miller's book offers both general and specific information about controlling the spread of nonnative invasive plants. The guide provides illustrated directions for applying herbicides to target nonnatives while avoiding damage to desirable plants, as well as suggestions for burning, hand pulling, and mechanical treatments. Specific prescriptions for the nonnative invasive plants highlighted in the guide follow the general guidelines.

Miller stresses that actual eradication is just one phase of an integrated approach that involves continuing surveillance and rehabilitation. "It is important to realize that eradicating infestations of invasive plants usually takes several years of treatment and many more of surveillance," said Miller. "The rehabilitation phase is extremely important. To protect and stabilize the soil, fast-growing native plants that can outcompete and outlast any surviving nonnative plants must be planted soon after eradication."

Miller's guide will serve as the instructional framework for a regional workshop on nonnative invasive plants held on June 4-5 in Greenville, SC. "Terrestrial Plant Invasions in the Temperate South: The Problem, Consequences, and Taking Control" is designed to inform participants about the many resource and social problems caused by nonnative invasive plants in Southern forests, and to provide information about identification and control. For more information, visit the workshop website at

For more information: Dr. James H. Miller at (334) 826-8700) or

Nonnative Invasive Plants of the Southern Forests (GTR SRS-62) is available online in pdf format. To request a printed copy, call (828) 257-4830, or email and ask for GTR-SRS-62. Copies can be requested by mail from:

Southern Research Station Publications
200 W. T. Weaver Blvd.
P.O. Box 2680
Asheville, NC 28802

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