Managing Nuisance Aquatic Plants
Identifying the Problem
For effective control and management, the first step is to identify the plants. Aquatic plants fall into two broad categories: vascular plants and algae.
Vascular aquatic plants have built-in transportation systems for water and nutrients, just as familiar garden plants do. Vascular plants can be further divided into submergent, emergent, floating, and marginal species. Submergent plants are usually attached to the bottom, and most of the plant is underwater. Emergent plants are typically rooted in shallow water with the main body of the plant extending above the surface. Floating species are unrooted and free to drift with wind and current. Marginal species are rooted along the shoreline in heavily saturated soils or shallow water.
Algae include free-floating, single-celled species (phytoplankton) and filamentous species. Phytoplankton are usually beneficial; they form the base of many aquatic food chains. Filamentous algae grow in long strands that may resemble green cotton candy and are often referred to as pond scum or moss. Species such as chara (muskgrass) look like vascular, submergent plants, but are really algae. Chara has a distinctive garlic-like odor when crushed.
Photos, diagrams, and detailed descriptions of aquatic plants can be found in the Pond Manager Diagnostics Tool, provided by the Texas Cooperative Extension Service. If you still need help identifying plants in a private lake or pond, contact a commercial pond manager or your county extension agent. For plants in public water, contact a fisheries biologist at Texas Parks and Wildlife Department.