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Aquatic Plant ID

They go by different names. You may call them “weeds,” “grass” or “moss.” Aquatic plants are an integral part of the Tennessee River’s ecosystem, whether providing nutrients for the species at the bottom of the food chain, cover and ambush areas for largemouth bass or food source for the multitude of local waterfowl.

This guide provides information to help you understand when these plants are most productive, where they grow and—most importantly—help you identify them. Whether you are an angler, property owner or any other lake user, we invite you to learn more about the aquatic plants present in our Tennessee Valley region reservoirs.

The guide also offers season-by-season tips for fishing among these plants.

Floating and Floating Leaf Plants

Water Primrose

While most species of water primrose (Ludwigia sp.) are native to the region, Ludwigia hexapetala, Uruguayan water primrose, is non-native. Once water primrose reaches the surface, it will rapidly spread out across the water's surface, forming interwoven, impenetrable mats.

Water Primrose

Description

Water primrose is a mat-forming perennial with floating or creeping stems. Leaves of the creeping stems are rounded or spoon-shaped and often occur in rosettes. The flowering stems are erect and up to 3 feet tall. The leaves on the flowering stems are alternate, narrowly elliptical to lance-shaped, and up to 4 inches long. Bright yellow flowers with 5 petals up to 1 inch long occur on stalks from the axils of the upper leaves. The fruit is a cylindrical capsule 1 to 2 inches long, which dries and splits open to disperse seeds.

Habitat

Most water primrose is native to the region. Water primrose grows on mud or in shallow water. Extensive growth can block small streams and shallow reservoir inlets. However, the native species are less aggressive and less of a problem than the non-native Uruguayan water primrose. Water primrose occurs throughout the Tennessee Valley region, most commonly found around shorelines, in ponds and along small streams.

Identifying Features

What It Looks Like—Water primrose is characterized by a large stem with alternating leaves. Leaves at the end of floating stems will often be arranged like a rosette with yellow flower visible.

Where to Find It—Water primrose is highly adaptable and can be found growing on nearly any shoreline out into 5 or 6 feet of water.

Max Depth—0 to 6 feet

Similar Species—Water primrose looks similar to alligator weed; however, alligator weed has opposing leaves, a hollow stem and small white flower.

Seasonal Fishing Techniques

Spring—As water primrose emerges from both shoreline and near-shore areas, vertical stems provide optimal opportunity for a swimbait or swimjig.

Summer—Once water primrose reaches the surface, it will begin to rapidly spread out across the water's surface, forming interwoven, impenetrable mats. As stems fall horizontally, new roots can form where leaves previously existed and quickly root in the sediment. A yellow flower will begin to appear at the peak of summer. Once growth increases and mat formation begins, fishing water primrose can become quite difficult. Fishing edges is most effective with a jig or senko.

Fall—Water primrose will reach peak growth in the fall, and fishing will remain difficult. Run weedless topwater across and over holes in water primrose (heavy braid recommended), or fish edges.

Winter—Water primrose will survive mostly as a rhizome until the following spring. Dead stems of water primrose may be present through mid-winter. Fish these by hopping a jig through and across leftover plant matter.

Drawbacks

Because of its aggressive nature, water primrose often causes conflicts with other water uses, including making shoreline access impossible. This species is commonly managed in a reservoir setting.

Shoreline Plants

Water Primrose

While most species of water primrose (Ludwigia sp.) are native to the region, Ludwigia hexapetala, Uruguayan water primrose, is non-native. Once water primrose reaches the surface, it will rapidly spread out across the water's surface, forming interwoven, impenetrable mats.

Water Primrose

Description

Water primrose is a mat-forming perennial with floating or creeping stems. Leaves of the creeping stems are rounded or spoon-shaped and often occur in rosettes. The flowering stems are erect and up to 3 feet tall. The leaves on the flowering stems are alternate, narrowly elliptical to lance-shaped, and up to 4 inches long. Bright yellow flowers with 5 petals up to 1 inch long occur on stalks from the axils of the upper leaves. The fruit is a cylindrical capsule 1 to 2 inches long, which dries and splits open to disperse seeds.

Habitat

Most water primrose is native to the region. Water primrose grows on mud or in shallow water. Extensive growth can block small streams and shallow reservoir inlets. However, the native species are less aggressive and less of a problem than the non-native Uruguayan water primrose. Water primrose occurs throughout the Tennessee Valley region, most commonly found around shorelines, in ponds and along small streams.

Identifying Features

What It Looks Like—Water primrose is characterized by a large stem with alternating leaves. Leaves at the end of floating stems will often be arranged like a rosette with yellow flower visible.

Where to Find It—Water primrose is highly adaptable and can be found growing on nearly any shoreline out into 5 or 6 feet of water.

Max Depth—0 to 6 feet

Similar Species—Water primrose looks similar to alligator weed; however, alligator weed has opposing leaves, a hollow stem and small white flower.

Seasonal Fishing Techniques

Spring—As water primrose emerges from both shoreline and near-shore areas, vertical stems provide optimal opportunity for a swimbait or swimjig.

Summer—Once water primrose reaches the surface, it will begin to rapidly spread out across the water's surface, forming interwoven, impenetrable mats. As stems fall horizontally, new roots can form where leaves previously existed and quickly root in the sediment. A yellow flower will begin to appear at the peak of summer. Once growth increases and mat formation begins, fishing water primrose can become quite difficult. Fishing edges is most effective with a jig or senko.

Fall—Water primrose will reach peak growth in the fall, and fishing will remain difficult. Run weedless topwater across and over holes in water primrose (heavy braid recommended), or fish edges.

Winter—Water primrose will survive mostly as a rhizome until the following spring. Dead stems of water primrose may be present through mid-winter. Fish these by hopping a jig through and across leftover plant matter.

Drawbacks

Because of its aggressive nature, water primrose often causes conflicts with other water uses, including making shoreline access impossible. This species is commonly managed in a reservoir setting.

Submersed Plants

Water Primrose

While most species of water primrose (Ludwigia sp.) are native to the region, Ludwigia hexapetala, Uruguayan water primrose, is non-native. Once water primrose reaches the surface, it will rapidly spread out across the water's surface, forming interwoven, impenetrable mats.

Water Primrose

Description

Water primrose is a mat-forming perennial with floating or creeping stems. Leaves of the creeping stems are rounded or spoon-shaped and often occur in rosettes. The flowering stems are erect and up to 3 feet tall. The leaves on the flowering stems are alternate, narrowly elliptical to lance-shaped, and up to 4 inches long. Bright yellow flowers with 5 petals up to 1 inch long occur on stalks from the axils of the upper leaves. The fruit is a cylindrical capsule 1 to 2 inches long, which dries and splits open to disperse seeds.

Habitat

Most water primrose is native to the region. Water primrose grows on mud or in shallow water. Extensive growth can block small streams and shallow reservoir inlets. However, the native species are less aggressive and less of a problem than the non-native Uruguayan water primrose. Water primrose occurs throughout the Tennessee Valley region, most commonly found around shorelines, in ponds and along small streams.

Identifying Features

What It Looks Like—Water primrose is characterized by a large stem with alternating leaves. Leaves at the end of floating stems will often be arranged like a rosette with yellow flower visible.

Where to Find It—Water primrose is highly adaptable and can be found growing on nearly any shoreline out into 5 or 6 feet of water.

Max Depth—0 to 6 feet

Similar Species—Water primrose looks similar to alligator weed; however, alligator weed has opposing leaves, a hollow stem and small white flower.

Seasonal Fishing Techniques

Spring—As water primrose emerges from both shoreline and near-shore areas, vertical stems provide optimal opportunity for a swimbait or swimjig.

Summer—Once water primrose reaches the surface, it will begin to rapidly spread out across the water's surface, forming interwoven, impenetrable mats. As stems fall horizontally, new roots can form where leaves previously existed and quickly root in the sediment. A yellow flower will begin to appear at the peak of summer. Once growth increases and mat formation begins, fishing water primrose can become quite difficult. Fishing edges is most effective with a jig or senko.

Fall—Water primrose will reach peak growth in the fall, and fishing will remain difficult. Run weedless topwater across and over holes in water primrose (heavy braid recommended), or fish edges.

Winter—Water primrose will survive mostly as a rhizome until the following spring. Dead stems of water primrose may be present through mid-winter. Fish these by hopping a jig through and across leftover plant matter.

Drawbacks

Because of its aggressive nature, water primrose often causes conflicts with other water uses, including making shoreline access impossible. This species is commonly managed in a reservoir setting.