BAD SEED: A REAL-LIFE INVASION OF ALIENS
Out of their element, once-good plants turn into life-sucking enemies.
By: "Mike Penprase"
Springfield News-Leader
About the Author
HIGHLANDVILLE — When Gary Pfalzbot and wife Pam moved here from California several years ago, they immediately began battling kudzu growing from a neighbor’s property onto their land.
Kudzu is a member of the pea family and puts out vines that can grow one foot a day. Fighting it consumed the Pfalzbots’ spare time and various patches of their property.
Until they brought in a secret weapon — goats. “What I’ve found is you need at least five (goats) per acre for it,” he said. “It grows pretty rampantly. But at the same time they will eat all the way to crown root.”
Introduced from China in the late 1800s as forage and for erosion control, kudzu is considered a major problem in the southeast United States and is quickly overtaking land in Missouri. Once considered a botanical godsend, it now consumes farmland, squeezes life from trees by robbing them of sunlight and can crush an abandoned home or barn.
Kudzu is one of several wonder plants that are creating a world of woe in the Show-Me State.
That seems the conclusion of everyone — from state legislators to ecologists — about non-native plants, most introduced to the region with well-intentioned reasons.
The list of once-touted, now-despised plants is long and has a long history.
They run from the thorny-topped teasle brought to America by colonists to process wool cloth, to the chinese lespedeza, introduced to control erosion along new highways.
Kudzu and two kinds of teasle, which the Missouri legislature decided to name as noxious plants, are a small portion of plants considered unwanted for a variety of reasons.
Other plants placed on the state Department of Agriculture’s noxious weed list include musk, Scotch and Canada thistles, multiflora rose, bindweed, purple loosetrife, Johnson grass and, not surprisingly, marijuana.
Being named a threat to agriculture isn’t the only reason plants get shunned.
The federally sponsored Alien Plant Working Group lists over 230 plants — some considered popular garden plants — as threats to native species.
Compared with plants threatening agriculture, those threatening native plants often get overlooked, said Tim Smith of the Missouri Department of Conservation’s natural history section.
“Some plants are declared noxious because they get in pastures and can take over areas,” he said. “There’s always a lot of support for declaring them noxious because they have an effect on agriculture.
“But there are other plants that are more of a concern to an ecologist because they spread across native systems. They may have no economic effect but they’re changing the landscape.”
That’s happened for centuries — from European sailing ships emptying ballast containing soil filled with European plant seeds to modern-day hikers taking seeds stuck to their socks into wilderness areas.
Alien plants cause problems nationwide, from imported trees clogging the Everglades to weeds taking over grazing range in the West.
One plant stands out as a good plant gone bad in Missouri, said longtime University Outreach and Extension Service horticulturalist Gaylord Moore. “We got ourselves in a bind several years ago with multiflora rose,” he said. “It got started years ago by agriculture agency people, the Missouri Department of Conservation, University Extension because we thought it was a plant with a sole purpose as a living fence.”
The plant was seen not only as cheap fencing, but as wildlife habitat.
Yet too little research was done before the plant was introduced. State officials didn’t realize until it was too late that birds ate the plants’ fruits and carried its seeds far and wide. An eradication campaign had to be started, Moore said.
“If it hadn’t have been for the problem with the birds, the multiflora rose probably would have been functioning as it was intended to,” he said.
Moving to the Ozarks
Another plant with a cloudy history has found a home in the Ozarks.
Although theories on how musk thistle got to Missouri vary, it has become a colorful and thorny headache for farmers.
Capable of covering pastures in short order, plants that produce thousands of wind-blown seeds have been fought by cutting them down, using herbicides or by pulling them from the ground.
Although landowners who refuse to clear their land of musk thistle have been taken to court in Greene County, in recent years the county has relied on a tiny ally to fight the plant — the thistle weevil.
When his department gets a complaint, inspectors check a map showing where thistle weevils have been found, county resource management director Tim Smith said.
Callers are told the insects that burrow into flower heads and kill them before seeds are produced are at work, he said.
But because thistles bloom before the weevils do their damage, it looks as if the county is overwhelmed, Smith said.
“We’ve got some places in the county where they’ve taken over the place,” he said of the thistle. “I’m hoping the weevil will be effective.”
Tom Hansen, an agronomy specialist with the Outreach and Extension, said he is convinced the flower head and rosette weevils are effective.
“With the weevil, you’ve got a normal biological cycle. It’s like the lemmings and the foxes,” he said.
Working with weevils takes some adjusting, he said.
It might not seem sensible, but it’s necessary to leave thistle standing until July or August so the weevils can mature and be ready to fight the good fight anew next season.
Good plants gone bad
Pfalzbot not only knows what havoc a non-native plant can have when it runs amok, but also about the mixed blessings such plants bring.
Encouraged by the way over 30 goats took a bite out of kudzu on his Highlandville property, Pfalzbot set up a Web site promoting goats as a way to control kudzu.
He’s also familiar with Web sites that paradoxically extol the virtues of kudzu. There are Web sites describing how to use kudzu vines to weave baskets to making kudzu jelly.
He hasn’t made any baskets, but has cooked up kudzu jelly, Pfalzbot said.
Call it a love-hate relationship.
Purple blossoms that bloom in August and have an odor resembling apple and grape enticed him to cook up some jelly.
Even though the process created an odor so objectionable his wife almost ran him out of the kitchen, the jelly was unique, he said.
“It turned out all right; it jelled up all right,” he said. “Have you ever tried grapefruit jelly? It tastes like grapefruit jelly.”
Still, Pfalzbot so despised kudzu that he worked with state Rep. Jim Kreider to have it declared a noxious weed in Missouri.
Taking control
Although he didn’t know about Pfalzbot’s goats eating kudzu, Wilson’s Creek National Battlefield Chief of Resource Management Gary Sutton said goats will be recruited to help fight sericea lespedeza that wasn’t on the battlefield when Union and Confederate soldiers faced each other in August 1861.
What’s known as chinese lespedeza was introduced to stop erosion along state highways. It gets so aggressive, it crowds out native plants, he said.
Later this summer, goats will be turned loose on a 10-acre plot to see if they like the plants more than cattle do, which won’t eat mature plants, he said.
Then, there’s the effort to protect bladderpod that clings to rocky glades in the battlefield, Sutton said.
“We’ve got three annual brome species on the glade areas here that compete with the bladderpod, which is an endangered (species),” he said.
While fighting the likes of musk thistle has involved anything from brushogging to using weevils that kill the plant’s flowers before they can seed, controlling brome involves using weed trimmers to cut off seed heads, he said.
But it can take years to bring such plants under control, he said.
Often, controlling objectionable plants means maintaining constant vigilance, Sutton said.
“Actually, one of the best bangs for your buck is to look at what (species) is coming in,” he said. “Reconnaissance and keeping the exotics out is the best.”
Kudzu
•Size: Starts out a small, nondescript vine of a few inches. And then ... (hit the theme from “Jaws”...)
•Description: The legume is a spiny, “hairy” vine with triple-edged dark-green leaves. Large patches of the plant resemble poison ivy.
•Its allure: When it first began to explode in the South, many people fought its destruction because of its lovely smell. But to most folks, it smells like hours of work and, for many farmers, bankruptcy.
•Its threat: It’s America’s most destructive and despised weed. It can take over a yard, a grazing acre or a farm in weeks. It has been the ruin of many farmers and ranchers and has taken on a mythology all its own. The myth that it can grow a foot per day? It’s no myth.
•History: Imported from Japan to decorate a garden at the Japanese Pavilion at the Philadelphia Centennial Exposition. In the early 1900s, was considered a convenient forage for livestock during dry seasons as well as an effective plant for erosion control. In the 1950s and 1960s, kudzu was planted along Missouri highways to control erosion.
•Where it’s found: It grows fastest in rough, well-drained land and sandy, deep-loam soils. But it can invade forests. The “kudzu belt” extends from Connecticut to Missouri and Oklahoma, south to Texas and Florida. Kudzu has been found in Jackson, St. Louis, Howard, Christian, Wayne, Reynolds, Douglas, Newton, Lawrence, Ralls and Taney counties.
•How to control it: Ha! You can only hope to contain it. Kudzu at full strength can down power poles, snap powerlines, crush buildings and drain the life from full-grown trees. The plant is at its most vulnerable when it is young and during extreme cold. Total eradication of parts of the plant during winter will kill it eventually. Burning will kill only the very young plants. Livestock will eat kudzu. Any plants that remain after four years of grazing can be spot treated with a herbicide. If the infestation is allowed to grow more than 10 years, it is all but impossible to kill off.
•Musk thistle
•Size: Grows up to 6 feet tall.
•Its appeal: Many are charmed by its pompom-like purple flowers and large green rosette-shaped leaves.
•The threat: It can invade grasslands, even amid healthy, dense vegetation. It can quickly kill off row plants, native species and grazing grasses. It is no good for livestock grazing because of its spiny tissue and lack of nutrients.
•Where to find it: Fields, pastures, wildlands along farm roads and highways. It grows wild in more than 40 U.S. states and can be found in every Missouri county.
•How it lives: The musk thistle has a two-year life cycle. The plant takes root as a rosette-shaped sprout of leaves in the spring, hunkers down to survive winter, then sends up flowering stalks the following spring.
•How it explodes: Within 10 days of flowering, seeds mature and are carried off by the wind. More than 11,000 seeds can be sent into the air by a single plant.
•How to control it: To stem its growth, you must kill the plant and shut off its seed production and distribution. If you find a single plant in your yard, pull it out by the roots, wrap it in plastic and dispose of it properly. Dealing with it in larger numbers is tougher.
Multiflora rose
•Size: Can grow to 6 feet tall, but is usually 3-4 feet.
•Description: Sprays of half-inch white flowers cascade from the green spreading plant.
•Its allure: When flowering, it’s a lovely shrub.
•Its threat: It’s the botanical version of “Gremlins.” It will take over an open space in no time, and its thorny stalks will bedevil anyone trying to remove it. It smothers crops and native plants.
•History: Introduced to the East Coast from Japan in the 1880s. Planted in the Midwest as “living fences.”
•Where it’s found: Fields, pastures along roads and highways. Can also thrive in thick forests. Can be found in every county in Missouri.
•How to control it: It call be pulled. In areas of light infestation, mowing and cutting can be effective if repeated at least three times during the season for two to four years. Some herbicides have proved effective. No natural insect controls have yet been developed.
