Weed Management Handbook

diquat

Rate 1 to 4 lb ai/A (0.5 to 2.0 gal per surface acre)

Time Apply when weeds are actively growing and water temperatures are above 50°F.

2,4-D dimethylamine salt

Rate 2 to 4 pints/A product in 20 to 100 gal/A

Time Apply in spring or early summer when aquatic weeds appear, prior to bud or bloom.

Remarks Repeat as necessary to kill regrowth or missed plants; use 4 pints/A rate when plants are mature or dense.

2,4-D dimethylamine salt

Rate 1-1/2 to 2 quarts of product in

400 to 800 gallons of spray per acre.

Time Apply in spring or early summer when weeds appear, but prior to bud or bloom.

2,4-D

Rate 2 lb ae/A (1.15 gal/A ) with 100 to 400 GPA spray mixture with power sprayers

Time Apply in spring or early summer; if needed, a second treatment may be applied before September.

2,4-D

Rate 2.3 gal/A in minimum spray volume of 5 gal mix/A with surface applications; 2.3 gal/A through standard boom system with minimum of 5 gal/A of spray mix.

Time Apply in spring or early summer; if needed, a second treatment may be applied before September.

2,4-D

Rate 2.5 to 6.2 gal/A-ft as concentrate

Time Apply when plants are actively growing (spring or early summer).

Remarks For use in quiescent or slow-moving waters; apply to moving bodies of water only while traveling upstream to prevent concentration downstream. No use restrictions for swimming, fishing, watering livestock or domestic purposes other than noted below.

2,4-D

Rate 2.5 to 6.2 gal/A-ft as concentrate

Time Apply when plants are actively growing (spring or early summer).

Remarks For use in quiescent or slow-moving waters; apply to moving bodies of water only while traveling upstream to prevent concentration downstream. No use restrictions for swimming, fishing, watering livestock or domestic purposes other than noted below.

acrolein

Rate Up to 8 ppm

Time Apply when weed growth is no more than 4 to 6 inches tall.

Remarks Repeat treatments every 3 to 4 weeks during the remainder of the season.

copper sulfate pentahydrate and copper compounds2

Rate 0.25 to 1 ppm poured directly into water of irrigation channels, injected into the water column, suspended in burlap bags, or applied over water surface of impoundments.

Time Apply early in spring and at 2- to 3-week intervals thereafter.

Proper stewardship of water resources is necessary if aquatic vegetation control is to be more than temporary. Management must begin by evaluating all uses of a given body of water. Chemical, biological, and physical factors should be well understood and manipulated if possible to get the maximum use of the water for the benefit of the greatest number of people. Before undertaking management of aquatic weeds, consider the following:

Biological aspects