Killer Weed

It was at Browning Elementary, a neighborhood public school near the Heights, that The Beast first made its appearance.

Ron Jones, a biologist with the local field office of the U.S. Fish and Wildlife Service, had volunteered to help the school build and maintain a Wetlands Demonstration Pond as a teaching tool.

In the fall of 1997, a few months after the small pond opened, he saw that it had become completely covered by a strange, leafy growth that seemed to have appeared overnight. He took a rake and removed all the vegetation.

Last April, he returned to the school. Again the pond was completely overrun with the green plant, which had grown so thick it acted like a tarpaulin, cutting off any sunshine or oxygen to the underwater plants trapped beneath it.

"I had no idea what it was, really," Jones says. "I just knew it was something that was growing phenomenally fast."

As surprised as he was, he soon came in for a bigger shock. School staffers told him that they had completely raked out the pond several times in the months between Jones's visits. Each time the green plant had quickly covered the water again.

A baffled Jones sent samples to area plant biologists. It took a while, but eventually they figured out what the plant was. Salvinia molesta, a South American plant that had lived up to its ominous name by rapidly choking waterways in Australia, Africa and Asia, had made its way to America.

The plant floats on fresh water, pushed around the surface by the wind, with plants sometimes stacking on top of each other to a depth of two to three feet. Reproducing asexually, it essentially clones itself at an extraordinary rate, doubling the water area it covers in a week and wreaking havoc on fragile aquatic ecosystems. In New Guinea, according to one study, a few plants grew within eight years into a mat covering 96 square miles.

Banned from import into the United States, the plant had attempted an abortive foothold here a few years ago, when it was discovered in a small pond in South Carolina and quickly eradicated. The Browning Elementary development was much more severe and serious, but local experts crossed their fingers that somehow the plant had been confined to the school's pond. If Salvinia molesta made its way to any of Texas's lakes or rivers, it could spawn a disaster that would take millions of dollars to fix and might require herbicides that could cause more problems than they solved.

Officials with state and federal wildlife agencies printed fliers and put notices in relevant newsletters saying Salvinia molesta had been found and asking to be contacted in the event of any new sightings. A few false alarms, a couple of private-pond infestations that were easily eradicated, and officials thought they might have dodged a bullet. Maybe molesta would not become the watery equivalent of the fire ant, a pest that had inadvertently been brought into the U.S. decades ago and was now a tiresome fact of Southern life.

In June, Dr. Jim Hyde of the Sabine River Authority was swimming with his family in Toledo Bend Reservoir, a large reservoir that spans the Texas-Louisiana border. He saw a green, leafy plant float by, one that looked like the plant described on the notice sent to employees of his office.

Salvinia molesta, The Beast that no one wanted to tangle with, had made the jump to Texas's public lakes.

No one's sure how molesta, also known as Giant Salvinia, made its way to Texas. Authorities suspect local nurseries, unaware of its prohibited status, sold or even gave away the plant as a fast-growing water-garden accessory. The feds are investigating but have found property owners clamming up when they discover law-enforcement officials asking questions.

More important than how it got here is how fast it will spread. Officials don't know when it will branch out to other lakes and waterways, but they know how it will happen: humans will unwittingly distribute it to local waters that otherwise would never get infested.

As little as a leaf or small chunk of a live molesta is all that is needed to start a new outbreak, a leaf or chunk that could easily attach itself to a boat or be sucked into, and later blown out of, the ballast system of a Jet Ski.

"All it takes is one guy who doesn't wash off his trailer after he goes fishing, and then he moves on to another lake and he takes it with him," says Rhandy Helton, a Texas Parks & Wildlife scientist in Jasper.

Helton and his partner, Larry Hartmann, are counting the days until molesta shows up in Lake Sam Rayburn, one of the most popular lakes in Southeast Texas. Rayburn is a half-hour's drive from Toledo Bend -- on a completely separate river system -- and fishermen who are having no luck on one think nothing of picking up their boats and driving over to the other. Every bass boat tooling down Texas 255 could be carrying the piece of Salvinia molesta that starts a major infestation of Rayburn.  

Helton and Hartmann, working out of a tiny portable building deep in the East Texas woods, are on the front lines of the battle against molesta. "It's just eating our lunch," Helton says.

Molesta will never completely cover any of Texas's large lakes, but it can easily take over the coves and byways that dot the shorelines of those reservoirs. Those are the prime fishing areas and the spots where expensive lakeside homes are built. After Giant Salvinia enjoys a prime growing season, those fishermen and homeowners might find a rude shock when they see their favorite water spots covered with a thick, green vegetative mat.

Molesta is much more aggressive than hydrilla, a somewhat similar plant that has also caused problems in Texas. In one of the several private-pond Giant Salvinia infestations authorities dealt with since the discovery at Browning Elementary, the molesta growth was so thick that ducks nailed mid-flight by hunters had landed with a dull thud on the vegetation, unable to pierce through to the water. ("When this plant really gets going, you can roll a golf ball across it and it'll never get wet," Hartmann says.) And unlike hydrilla, which bass fishermen like because it attracts their quarry, Giant Salvinia has no redeeming features for sportsmen.

Perhaps more financially ominous than spoiling fishing sweet spots or lakeside views is the threat of what might occur if molesta makes its way past the dams that create Texas's lakes. Galveston Bay is safe -- the plant can't survive salt water -- but the water systems of Toledo Bend and Rayburn, and other lakes, are used to irrigate the rice fields that are a backbone of the local agricultural economy.

"You could get one piece that gets by the screen [of the irrigation system] or gets on a turtle's back or the legs of a waterfowl, and you'd get this in the rice fields," Helton says. "It's scary."

With doomsday scenarios aplenty, local and federal authorities have created a Giant Salvinia Task Force, featuring the resources of such groups as Texas's and Louisiana's wildlife authorities, the National Park Service, U.S. Geological Survey and Department of Agriculture, the U.S. Army Corps of Engineers and Texas A&M and Florida A&M universities. The task force met in September at the Ramada Inn at Bush Intercontinental Airport to begin mapping out a strategy to take on the unprecedented challenge.

They've heard the horror stories from Australia, where all manner of eradication methods have been used without success. They're hoping that by catching the phenomenon early, they will be able to control it before it gets to be the problem it has become in other places.

Typically, there are three main ways to deal with aquatic infestation of so-called exotic nuisances: mechanically, biologically and chemically. Put simply, you see if you can pull the plant from the water and hope you get it all; you find a bug that will eat it; or as a last resort you use herbicides.

Molesta will never be contained merely by mechanical means, officials are sure. The plant reproduces too fast, and such machines are too expensive, to make the effort feasible. Officials can also "draw down" the level of lakes by a couple of feet, stranding the plant on the shore and letting it wither away, but that isn't likely to kill enough of the weed, either.

The biological option offers slightly higher hopes. The Salvinia weevil is in regular use in Florida, where it's used to battle Salvinia minima, a more common and less aggressive form of Giant Salvinia. The tiny bug eats nothing but salvinia plants, scientists say, meaning it won't destroy desirable vegetation. Plans are underway to collect the bug -- a labor-intensive, not inexpensive job -- and get the necessary permits to transport it across state lines next spring.

"We're hopeful this insect will provide a lot of assistance in getting rid of the plant; it can get into places where the water is too remote or shallow for us to get in there," Helton says. "It's shown real promise, but I don't want to give out any false hopes. I've never seen any biological control that can be the whole answer."

"It's just one tool in the tool box," says Hartmann, noting that molesta growth rates can outpace the bug's consumption rates. The bug is more of a crawler than a flier, too, and requires all but being placed on the plants for a population to take hold.  

That leaves the third option, herbicides, and that option is the touchiest one of all. The Texas Parks & Wildlife Department has plenty of critics who charge the agency is all too eager to use chemicals in its fights against various nuisance plants.

"I get real worried when they reach for the herbicides," says Sue Pittman, a network coordinator for the Chemical Connection, a statewide group that monitors the TP&WD. "They should be thinking about mechanical means; if this plant is not attached to the bottom of the lake, they should get a big sucker-upper and just suck it up. It doesn't make sense to use chemicals."

Government authorities and the state's bass fishermen, in fact, recently tangled noisily over plans to use herbicides to control hydrilla in Central Texas's Lake Bastrop.

"Eighteen months ago the Lower Colorado River Authority put a bunch of chemicals into Lake Bastrop to kill the hydrilla, and they had a near-riot on their hands," says Neil Carman, a director of the Lone Star Chapter of the Sierra Club. "The bass fishermen protested and the two sides got together, but the whole thing just about disintegrated. We were ready to say, 'Screw you, we'll just see you in the Legislature.' They were very concerned that herbicides would be used that would kill vegetation that's good for the habitat."

Partly as a result of that skirmish, various bass-fishing groups formed an umbrella organization called SMART, or Sensible Management of Aquatic Resources Together.

SMART vice president Ed Parten says he's already involved in the fight against Giant Salvinia. Although the group is trying to raise funds to purchase harvesters to battle various types of noxious vegetation (such machines can go for as much as $200,000), he says he's resigned to the fact that some herbicides will be needed.

"I know some type of chemicals will be used, but if it's to the degree of severity that we have seen in the past it will be very detrimental," Parten says. "We're extremely concerned about this vegetation and the possibility of what it will do.... We're scared to death of it; I don't know of one person who wants it in the water of Texas. [Using herbicides] is the price we might have to pay -- if you don't do it, this plant will kill everything else that's good in the water; it will choke it out and it won't live."

State officials, naturally, insist that they will be cautious and conservative in any use of chemicals. "We're not going to start a herbicide operation next week and nuke the lake, but [using chemicals] is something we're going to have to consider," Helton says. "We can target the plants that we want to spray."

There's nothing in the scientific research literature, by the way, that indicates there is any particular chemical, or chemical compound, that is very effective in eradicating Giant Salvinia. Australians have had some success with paraquat, but that substance -- known chiefly for its use in killing marijuana plants -- is banned by federal law from being used in U.S. waters because it's harmful to humans and can kill fish.

It's not only state agencies that Parten and other fishermen are worried about. Also posing a threat will be homeowners who find their lakeside lots now look like they are far from shore because the water is covered by a grassy-looking mat of plants. The state of Texas has few regulations against private use of herbicides on its waterways.

"Chemicals that you can get arrested for if you pour them on the ground, you are freely able to pour them in public waters," says Parten, whose group will be lobbying for tougher regulations in the upcoming legislative session. Homeowners who decide to take matters into their own hands may do more harm than good, he says.

"We're not a bunch of radicals here screaming 'No Chemicals.' We want the people who use chemicals to be responsible," Parten says.

Pittman, of the Chemical Connection, takes a harder line. "We really can't comprehend a situation where you would want to use chemicals, but we know there is one that might come up. This [Giant Salvinia] isn't one, if you think creatively. Just go and suck it out and suck it out again."

Just what methods will be used to fight The Beast have yet to be determined by the Task Force, but decisions will have to be made before warm weather and the prime growing season arrives. Whatever the plan is, it will likely cost millions of dollars in federal and state funds.  

Any hopes that a Texas winter would kill off molesta have been pretty much dashed. "I went over [to Toledo Bend] this week to see if the freeze we had did any damage to the plant," Helton said on New Year's Eve. "The plants were still bright green. It looks like the Christmas Week freeze did minimal if any damage. I don't think the plants are growing so aggressively now, because we're below the temperatures they need to do it. But if winter is not hurting it, then it's just waiting for spring, and it will really take off."

"Southeast Texas is just totally suitable for it," says Ron Jones, the federal biologist who first discovered the plant at Browning Elementary. "The potential for growth is mind-boggling. We know it's wintered through one year and maybe two. It's probably capable of surviving as far north as Dallas, and that takes in just about all of the major lakes we have. It's going to be an issue across all of the southeastern U.S."

Right now, officials are asking the public to report any Giant Salvinia sightings and to thoroughly wash off their watercrafts when leaving a lake. If molesta makes it to other Texas lakes or other states, it will likely do so through the courtesy of some careless boater.

The uncertainty of the coming spring, with its increased growth rates and increase in people using the lakes, is gnawing at the scientists fighting the problem. Whether Giant Salvinia undergoes a major outbreak and becomes a watery kudzu that eats up budgets for years to come, or whether the Toledo Bend infestation merely becomes a notable footnote in the nation's aquatic history, will not be known for some time.

"We're just learning as we go along. We're forced to, because this has shown up in our back yard," Helton says. "Sometimes you sit there and think about when that first fire ant crawled onto the dock in Mobile or New Orleans or wherever it was; if someone had just squished it, they would've saved us all a lot of trouble. The same thing here."

"We'll have a pretty good idea by this time next year how all this is going to go," Hartmann says. "We'll either be walking around with our heads hanging or feeling pretty good."

Even if some combination of mechanical, biological and chemical means becomes the answer, ridding the state of the plant will not be easy. "Even if we're feeling like we can get a handle on it, it's going to take several years for Toledo Bend to get back to normal," he says. "This thing is a booger.

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