By Brad Haire
University of Georgia
Japanese climbing fern climbs plants and chokes them. Cogongrass
forms a toxic mat. And they’re just two of many foreign plant
invaders that threaten Georgia’s forests and natural areas.
Cogongrass grows thick foliage about 4 feet high, said Chris
Evans, an invasive species and natural resource specialist with
the University of Georgia Bugwood Network.
The Bugwood Network is a Web-based system used to collect,
promote and distribute educational materials in entomology,
forestry and natural resources.
Forming thick clumps and releasing toxins that smother all other
plants, cogongrass can hurt natural wildlife and forestry
production. “It’s considered one of the worst weeds in the
world,” Evans said.
It’s already infested several southwest Georgia counties,
including a 20-acre site in Mitchell County. It has caused major
problems for some pastures and forests in Mississippi and
Florida. “We
want to find and suppress it before it becomes a problem in
Georgia,” he said.
The light fluffy seeds of cogongrass are easily carried by wind.
They also catch rides on vehicles. As a result, the plant fills
many roadside ditches in Mississippi, he said.
A native of southeast Asia, it was introduced into the Gulf
states early last century as packing for cargo shipments. Others
later tried it for livestock forage and erosion control.
Japanese climbing fern grows quickly over small trees and
shrubs, shades them out and kills them, Evans said. It grows up
taller trees, too, where it becomes an easy path for fire to
reach treetops.
“Just in the past year,” he said, “we’re seeing more of it in
pine stands in Georgia and natural areas.”
The Asian and Australian native has made it hard for some south
Georgia pine straw farmers to rake their straw, which they
bundle and sell as landscape mulch, he said. Alabama and Florida
officials regulate pine straw that enters their states for this
fern.
The plant was introduced into the United States in the 1930s as
an ornamental. It grows as fast as kudzu. If left unchecked,
kudzu can quickly take over a local area. But the Japanese
climbing fern can spread faster over greater distances, he
said.
It takes time for some invasive species to become problems, he
said. A population may be slow to establish. But once it does,
it can explode.
Invasive plant species like the Japanese climbing fern and
cogongrass may have been introduced decades ago, Evans said, but
they could now have the foothold they need to cause ecological
and economic damage.
Exotic invasive plants are found in almost every state. Georgia
has about 20 major ones, he said.
Many people think some common plants in Georgia are native
species, he said, but they’re exotic and potentially invasive
plants.
Privet, for instance, is a small bush usually found growing
under trees. It has white flowers and purple berries and can
outcompete native shrubs.
Wisteria is a popular landscape plant that sometimes escapes to
become wild and unchecked in wooded areas. Its showy purple
blooms can be seen growing on trees along some Georgia roadways
in spring.
The Georgia Exotic Pest Plant Council and the Bugwood Network
are sponsoring the Invasive Plant Control Workshop April 13 at
the UGA Rural Development Center in Tifton, Ga.
Participants will learn how to identify exotic, invasive plant
species, find out what measures are being taken to control them
and how they can help. For more information, call (229) 386-
3416. Or go to the Web site (www.ugatiftonconference.org).
