Hydrilla is an exotic plant that multiplies so rapidly it can choke a lake, killing native vegetation and decimating fish populations. It is a nuisance to boaters and a nightmare for lakefront developers. If left unchecked, it can effectively "kill" a body of water.

However, the methods used to rid Texas lakes of this predator are often as dangerous as the plant itself.

The Problem: Eradication vs. Management

Historically, the Texas Parks & Wildlife Department (TP&WD) has sought to solve the Hydrilla problem through total eradication. This usually involves two controversial methods:

1. Grass Carp: Introduced to Lake Conroe in a massive research project involving 270,000 fish. The problem? They eat everything—the Hydrilla and all native vegetation—leaving the lake a biological desert.
2. Chemical Methods (Herbicides): Pesticides like Sonar have been linked to birth defects, liver disease, and cancerous tumors, in addition to causing massive fish kills.

The Solution: The Hydrilla Harvester

Recently, Governor George W. Bush, an angler of some repute, intervened to postpone chemical applications at Lake Bastrop. In a historic move, Bush arranged for the Lower Colorado River Authority (LCRA) to borrow a state-of-the-art mechanical harvester from the Tennessee Valley Authority (TVA).

Ray Scott, founder of B.A.S.S., noted that while these machines cost roughly $150,000, they are an environmentally sound, cost-effective, and practical solution. Unlike chemicals, the harvester is selective. It allows for "lane cutting," which maintains access for boaters while leaving enough habitat for fish to thrive.

How the Harvester Works

The machine is a marvel of aquatic engineering:

• Efficiency: It can cut one acre of Hydrilla per hour to a depth of five to six feet.
• Process: It cuts the vegetation, squeezes out the water, shreds the material, and returns it to the water as harmless organic matter.
• Safety: According to the Department of Natural Resources in Minnesota, where these have been used for years, the harvester does not harm fish populations.

A Century of Engineering

According to Pat McCarty of Texas Black Bass Unlimited, these harvesters have been around since about 1902. Originally created to clear weeds so that clean ice could be harvested from frozen lakes, they have evolved into 14,000-pound machines with cutting widths of up to 10 feet.

The industry leader, D&D Products, Inc. of Wisconsin, has been developing this equipment since the 1950s and supplies machines to 40 countries worldwide.

The Road Ahead for Texas

While the demonstration at Lake Bastrop is the immediate focus, state officials are already looking at long-term implementation. Dr. Larry McKinney, Senior Director for Aquatic Resources at TP&WD, is considering purchasing a harvester for a one-to-two-year study.

"I want to try a harvester for a year or so at a few smaller state park lakes," McKinney says. "I want to try cutting some ‘lanes’ through grassy areas and study the results."

If this test succeeds, it could mark the end of toxic chemical dumping in Texas waters and the beginning of a smarter, "S.M.A.R.T.er" era of lake management.

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Key Takeaways for the Archive:

Historical Trivia: The fact that these machines evolved from ice harvesting is a great piece of trivia that adds depth to the story.

The "Lanes" Concept: This article introduces the idea of "selective management"—cutting lanes for boats while keeping the grass for the fish.

The Political Shift: It highlights a rare moment of direct environmental intervention by then-Governor George W. Bush.