Skill Builder: Stopping Water Hyacinth
Don’t judge a plant by its petals.
By Mary O. Parker
There’s a reason the beguiling purple blossoms of the water hyacinth (Eichhornia crassipes) seem exotic. They are. The plant is originally from South America, and if it has its way, it’s not leaving Texas anytime soon.
These seductive beauties have infiltrated a growing number of our urban and rural waters, costing state and local governments thousands of dollars annually. According to T.J. Marks, division manager of the City of Houston’s Horticulture Department, in the last couple of years the invasive aquatic has been showing up in more places in the city than ever before. “And once established,” he says, “it’s a fight to eliminate it. It’s a daunting job.”
Marks cites the pond at Houston’s Hermann Park as a prime example. There, he says, it was purposefully planted by a Houston resident “probably not to be malicious. Instead, I think he didn’t fully realize the ramifications of what he was doing.” Water hyacinth has also been introduced, Marks adds, by folks emptying aquariums into city waterways.
Yes, the plant is so prolific that even that tiny amount can get it started on its aggressive path. Says Charles Hubbard, Interpretive Specialist at Caddo Lake State Park, where water hyacinth has been a problem for more than a decade, “The plants can overtake a natural ecosystem quite rapidly.”
“The real problem,” Marks explains, “is they wreak havoc with the native species because natives can’t out-compete the invasives. Any introduced plant, once you take it out of its own ecosystem, well there’s no control to keep it in balance. The population explodes because there’s nothing to keep it in check, it has no natural predators.”
“Water hyacinth is quite happy here,” says Hubbard, “because, for the most part, Texas is in a subtropical zone and climate conditions are almost identical to where it comes from. And here there are no natural consumers like there are in South America.”
It’s probably also happy here because it’s made friends, human friends who’ve been sweet-talked by the plant’s comeliness into helping it proliferate. But now that you know that water hyacinth’s beauty is only petal-deep, besides not planting it on purpose, what can you do to act as foe rather than friend?
For starters, Hubbard suggests that, after a day in the water, you check your boat, trailer and gear thoroughly for plant remnants. Before towing your boat and trailer home, look carefully around the prop, trolling motor, water intake and shaft. Also peruse paddles, nets, lures and “anything that’s been in the water. You don't want to bring it to another lake or body of water on accident.” At many lakes, he says, you’ll find special containers specifically for discarding any pieces you find.
In urban areas, says Marks, “It’s bad news to have it in a garden pond or aquarium.” No matter how isolated your backyard might seem it’s not worth taking the chance that the plant will spread to a nearby creek, runoff or storm drain.
When removing it from ponds and aquariums, Marks suggests, “Take it out and let it desiccate and die. Be really careful about where you put it while it’s drying. Be sure to keep it terrestrial.” Burning it isn’t necessary; just make sure it’s been out of water at least 48 hours before throwing it into a container that might accidentally collect water (like a trashcan).