Aquatic Vegetation Herbicide Control Water Use Restrictions1 – number of days after treatment before use in private waters only.
|copper sulfate 2||0||0||0||0||0||0|
|diquat||1-3 3||0||0||1||1-3 3||5|
|imazapyr||*14||0||0||0||120 9||120 9|
|triclopyr||*13||0||0||0||0 7||120 8|
1 Aquatic vegetation control can result in a period of low dissolved oxygen which can stress and/or kill fish. It is best to treat most aquatic vegetation early in the growing season, when the plant is rapidly growing. Treating small areas (e.g. 1/4) of pond at a time at 10 – 14 day intervals will allow for decomposition usually without causing an oxygen depletion.
2 If water is for drinking, the elemental copper concentration should not exceed 1.0 ppm (i.e. 4.0 ppm copper sulfate)
3 Depending on forumulation – Read label.
4 Length of use restriction for endothall varies with concentration used. Read label.
5 Do not apply within 0.5 mile of a functioning potable water intake.
6 Do not apply within 0.25 mile of a functioning potable water intake.
7 No restriction on irrigating established grasses but do not harvest hay for 14 days after application. Read label.
8 Or until non-detectable concentrations in immunoassay analysis.
# Minimum setback distances from potable water intakes required and laboratory tests to determine < 0.4ppm for use. Read label.
@ > 1/2 mile from potable water intake
9 Or until < 1.0 ppb
10 Do not use treated water to irrigate greenhouses, nurseries or hydroponics.
11 Sodium carbonate peroxy-hydrate
12 Water restrictions on 2,4-D vary with formulation, location, rate, and time of year. Read label. Read label.
13 Minimum setback distances from potable water intakes required and laboratory tests to determine < 0.4 ppm for use. Read label.
14 > 1/2 mile from potable water intake
15 Do not use water from any treated site for food crop irrication until residues are determined to be less than or equal to 1 ppb.
16 The drinking water restrictions are to ensure that consumption of water by the public is allowed only when the concentration of endothall acid in the water is less than the MCL (Maximum Contamination Level) of 0.1 ppm. Applicators should consider the unique characteristics of the treated waters to assure that endothall acid concentrations in potable drinking water do not exceed 0.1 ppm at the time of consumption.
17 The drinking water setback distance from functioning potable water intakes in the treated water body must be greater than or equal to 600 feet.
Additional information is available through the following references and websites
Aquatic Vegetation Identification Card Deck $12.00 includes postage. Produced by Dr. Michael P. Masser – Publication Number B6095
Distribution and Supply, Texas A&M University
PO BOX 1209, Bryan,TX 77806
or order on-line at:
Texas AgriLife Bookstore: agrilifelearn.tamu.edu