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Product Label SDS Sheet

Harpoon Granular is a chelated copper formulation that effectively controls  a vast variety of aquatic plants including Hydrilla. Harpoon Granular may be applied to slow moving or quiescent bodies of water, including lakes, fish hatcheries, potable water reservoirs, golf courses, and fire ponds.

Areas treated with Harpoon Granular Aquatic Herbicide may be used for fishing and swimming immediately after treatment.

How It Works

Since it's designed and formulated for going after rooted, bottom-growing plants, dosages are provided based on height of growth. It's ideal for early-season control when plants first appear, and for spot treatments in deep water.


Apply product uniformly at the rate of 2.0 pounds (29 oz.) per 1,000 square feet for each foot of plant growth height.



40# Bag

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Hydrilla Excellent
Water Lettuce Good
Elodea Good
Northern Naiad Good
Coontail Fair
Eurasian Watermilfoil Fair
Sago Pondweed Good
American Pondweed Good


Water Use Restrictions

Active Ingredients: Copper Ethylenediamine Complex
Weight % Active Ingredient: 9.87
EPA Reg.No. 8959-55
Number of Days
Human Drinking 0
Human Swimming 0
Human Fish Consumption 0
Animal Drinking 0
Turf Irrigation 0
Forage Irrigation 0
Food Crop Irrigation 0

*Consult Label for Exact Doses & Important Application Directions.

Harpoon Granular Application Example:

  • Sample 1,000 sq ft Lakeshore Lot,  2 Ft average plant hieght
    Amount of Harpoon Granular Required : 4 Lbs

For Best Results

HARPOON Aquatic Herbicide should be applied early in the day under bright or sunny conditions when plants are actively growing and water temperatures are at least 60°F. Treat when growth first begins to appear or create a nuisance, if possible.

Algae growth around target plants may interfere with uptake of HARPOON Aquatic Herbicide. Pretreat these areas with CUTRINE PLUS, or other EPA registered algaecides.


Note: In areas less than 1 ft. deep, reduce dosage by 2.4 oz. per inch of water per 1,000 sq. ft. so as to not exceed 1.0 ppm total copper.

Do not use in water containing Trout, Koi or hybrid Goldfish.

*All pesticides can be harmful to health and the environment if misused. Read the label and follow directions. Consult with your local regulatory agency before applying herbicides and algaecides to public waters. There are herbicides from other states that are either not licensed in Wisconsin or Illinois, or are not recommended by ABI.

A WI DNR Aquatic Plant Control Permit or DATCP Fish Farm License is required in WI in order to apply algaecides or herbicides. In addition ponds and lakes with overflows not contained on the property are required to obtain a WPDES permit. Illinois Residents are required to obtiain NPDES permits through the Illinois EPA.

In order to apply chemicals in liquid form within Wisconsin, the applicator must be licensed with the State.

Recommendations of pesticide or treatments for specific algae or aquatic plants are provided for general information purposes only - no warranties are expressed or implied.

* We do not ship EPA registered Algaecides or Herbicides to the following states:

Alaska - California - Connecticut - Delaware -  Hawaii - New Hampshire - New Jersey - New York - Maine - Maryland - Massachusetts  -Oregon - Rhode Island - Washington State - Vermont (for additional information about these restrictions please see shipping or terms and conditions).


Michigan Shipments

Aquathol K, Reward, Weedtrine D, & Sonar products can not be shipped without a permit on file.