"Water Weeds Can Affect Many Lives"

Orlando Sentinel, Osceola Section, 8 April 2007: J3
By Tina Bond

Cost of Invasive Weed Control | What's the big deal? | How did hydrilla & hygrophila get here? | Roles of native plants | How can I help?

Boaters at Lake Toho.

Attention all boaters, duck hunters, water skiers, lakefront home owners, environmentalists, and anyone else with an interest in Florida’s waterways and aquatic ecosystems: What do you know about HYDRILLA and HYGROPHILA, a.k.a., the “Terrible Twosome”?

Aquatic invasive weeds are a major problem in lakes, canals, rivers, and essentially any type of freshwater body in Florida, particularly, hydrilla and hygrophila. The “Terrible Twosome” have been problematic in Florida waterways since the 1950’s, spreading rapidly through the state, wreaking havoc along the way. That may sound a little harsh but these plants cost millions of dollars per year to manage. According to the Bureau of Invasive Plant Management, roughly $22.5 million was spent in 2005 for aquatic plant control in public waters, 44 percent of that, or $9 million, was for hydrilla control! It will cost close to $30 million to manage invasive aquatic weeds in 2006/07.

So, what is the big deal other than the fact that it costs taxpayers millions of dollars to manage these invasive aquatic weeds? The “Terrible Twosome” have significant impacts on native plants, wildlife, flood control structures, waterway navigation, and overall recreational water usage by a variety of people. Hydrilla and hygrophila spread in a very similar way, via fragments broken off from plants in the water. Both plants can grow in any type of freshwater. The only exception is that hygrophila grows primarily in flowing water. Not only do they spread very easily by fragments, the “Terrible Twosome” can grow in very low light levels. So even with very little light, the plants can still grow and thrive. Since hydrilla and hygrophila grow very quickly, in a variety of conditions, they out-compete our native plants, displacing them from their environment. Essentially, if the “Terrible Twosome” were in a race with our native plants, the “Terrible Twosome” would win by a long shot!

How did hydrilla and hygrophila get here? When the plants were brought here in the 50’s and 60’s, they were used frequently as aquarium plants. Once the owner of the aquarium no longer wanted the plants (or fish in the aquarium), they were dumped into the nearest body of water. Hydrilla and hygrophila were released into areas where they did not have their natural enemies to keep them ‘in-check’, and with optimal growing conditions in Florida, they spread rapidly through our waterways. It is the same reason there are python and piranha problems in South Florida.

Hydrilla wrapped around a boat motor.

You are probably thinking, “What does this have to do with me?” Well, let me give you a few examples:
Thousands of fishermen travel to Florida to enjoy the premiere bass fishing in our lakes. If we do not manage the “Terrible Twosome” over time the plants will completely take over the lake. If that happens, fisherman will not be able to navigate the water and catch those trophy bass because there will be too many weeds in their way! We stand to lose roughly $1.5 billion coming into Florida’s economy.

Many of our native plants and animals benefit greatly from a diverse ecosystem. Hydrilla and hygrophila out compete many of the native plants that provide food and shelter for animals and other organisms. If all that is left are hydrilla and hygrophila, what will animals do for food and shelter? Hydrilla can, in very low densities, provide some habitat for things like fish and turtles; however the negatives definitely out weigh the positives when it comes to providing the best habitat for our wildlife, especially when all that is left are the “Terrible Twosome”.

Lakefront home owners should be concerned because hydrilla and other aquatic invasive plants can clog up flood control structures. This can prevent the structures from functioning properly, resulting in flooding of the lakes, which can result in the flooding of your property!

What can you do to help? An informed public is our best line of defense when it comes to preventing hydrilla and hygrophila from spreading. The more informed our citizens are the better our chances are at managing invasive aquatic weeds. Join us Saturday, April 21st at Chisholm Park in St. Cloud for the “Keep Osceola Beautiful” Earth Day Event. There will be experts on site to talk about the “Terrible Twosome” and current chemical, biological and mechanical control strategies. UF/IFAS Osceola County Extension will also talk about a $2.881 million grant that was awarded to Osceola County to find new and alternative control methods for hydrilla and hygrophila. Come out to learn what you can do to help in the fight against invasive aquatic weeds. For more information please contact Dr. Tina Bond at tbon@osceola.org (www.osceola.ifas.ufl.edu) or go to http://www.osceola.org/ and click the “Keep Osceola Beautiful” link.