Water Primrose (Ludwigia spp.)

Water Primrose

Products to Control Water Primrose

GullWing contains the active ingredient, imazapyr, which inhibits the plant enzyme AHAS (acetohydroxyaced synthase). Habitat is a systemic herbicide that is effective on post-emergent floating and emergent aquatic vegetation. Imazapyr is effective at low-volume rates and does not contain heavy metals, organochlorides or phosphates, making it safe to humans and livestock. GullWing requires the use of a spray adjuvant when applying on post-emergent vegetation.

Redwing is a liquid diquat formulation that has been effective on coontail. It is a contact algaecide and herbicide. Contact herbicides act quickly and kill all plants cells that they contact.

Avocet is a glyphosate formulation that has been effective on water hyacinth. These are broad spectrum, systemic herbicides. Systemic herbicides are absorbed and move within the plant to the site of action. Systemic herbicides tend to act more slowly than contact herbicides. An aquatically registered surfactant (see the label) will have to be added to the glyphosate solution for good results.

Water primrose is a perennial plant that stands erect along the shoreline but also forms longrunners (up to 16 feet) that creep across wet soil or float out across the water surface. These runners form roots at their nodes. Leaves range from lance-shaped or willow-like (2 to inches long by 1/2 to 1 inch wide) on the erect stems to round or oval 91 to 2 inches in diameter on the floating stems. Leaves can be green to reddish depending on the species. The single flowers are yellow with 4 or 5 petals depending on the species. Flowers vary in size from 1 inch to 2 inches in diameter.

Water Primrose Control Options

Mechanical/Physical

Water primrose can be cut and the roots can be dug up but physical control is difficult because it can reestablish from seeds or remaining roots.

Chemical

The active ingredients that have been successful in treating water primrose include diqat (E), glyphosate (G) and imazapyr (E) E = excellent, G = good

Information and photos courtesy of:
Department of Wildlife and Fisheries Sciences, Texas A&M University
http://aquaplant.tamu.edu/