Teton® herbicide can make your submerged weed and algae problems disappear.

Now that Teton® herbicide and algaecide is registered for control of submerged weeds and algae in irrigation canals, people want to know more. Here are the frequently asked questions, and the answers.

What is Teton?

Teton is an aquatic herbicide and algaecide that contains the amine salt of the active ingredient endothall. German scientists first synthesized endothall in 1928. The endothall molecule is based upon a natural occurring chemical produced by blister beetles (cantharidin). Since 1958, endothall has been used extensively for aquatic weed control in ponds, lakes, and reservoirs throughout the United States. The United States Environmental Protection Agency (U.S. EPA) has now established tolerances for all irrigated crops and endothall (Teton) can now be used in irrigation canals without any restrictions on irrigation.

Will irrigation water treated with Teton injure crops?

When used according to the label, Teton is not phytotoxic to crops. Teton has been registered by EPA for use on all cropping groups grown in the United States.

How will Teton not injure crops, yet control algae and aquatic weeds?

Aquatic weeds and algae are very different than terrestrial crops. Aquatic weeds and algae do not have a waxy cuticle on the leaf or algae surface whereas terrestrial crops do have the waxy cuticle. Aquatic plants and algae are typically immersed in the treated water assuring complete exposure to the herbicide.

How long will it take to see results after a Teton application?

Symptoms on algae will appear in a few days. Algae will generally turn dark brown to black and deteriorate in a few days, depending upon the temperatures. Within the first week after a Teton application the majority of the leaves will senesce from the plant. The plants will also start to turn brown to black in color. After the first week, the stems are still present within the water column and it will take from 2-3 weeks for the stems to deteriorate enough that they will lie down on the bottom of the canal where they will slowly decay.

How does Teton break down in the environment?

It is broken down via microbial degradation. The microbes naturally occurring in the water use the endothall molecule as a food source; thereby, breaking down the endothall molecule into organic acids, carbon dioxide and water.

Is Teton toxic to fish?

Teton may be toxic to fish at rates above 0.3 ppm, however it does not bioaccumulate in the food chain.

Does Teton have a restriction on livestock watering?

No. The U.S. EPA has allowed for the removal of this restriction based on their risk assessment. (A Supplemental label is available from UPI).

What are the Teton application rates needed to control aquatic weeds and algae in my irrigation system?

The majority of applications will target algae. The rates needed for control are approximately 0.25 gallons of Teton® per cubic foot per second (CFS). applied over a 8-12 hour treatment period. If targeting weeds please see the Teton label for recommended rates and length of application.

How often will I need to make an application of Teton to control algae?

It will depend on the length of your growing season. Applications of Teton should provide 2-4 weeks of control, however growing conditions will dictate the duration.

How many miles of control can I expect downstream from one Teton application point?

Miles of control depend on water temperatures. Cooler water temperatures will facilitate more miles of control; whereas, warmer water will likely reduce the number of miles controlled.

My canal system discharges into a natural body of water i.e. river, lake, reservoir, etc. Do I have to close these discharges when I make a Teton application?

There are no discharge restrictions for Teton. However, some states have discharge limits under NPDES or other permitting processes. Check with your regulatory agencies. UPI recommends that not more than 0.3 ppm be returned to these systems.

Do I need a pesticide applicator license to apply Teton to my canal system?

It depends on your state regulations. Teton is a general use aquatic pesticide. In some states, an applicator license is required. Check with your state Department of Agriculture.

Can I purchase Teton directly from UPI?

For your convenience, both products are available through local distributors. Give UPI a call for a list of local distributors in your area.

What type of application equipment do I need to apply Teton?

In most cases, a small 12-volt pump with low flow meters and or inline orifices will be sufficient. Most agricultural pesticide suppliers in your area can help you choose the equipment needed.

What will the pending NPDES requirements mean for Teton applications in 2010, 2011 and beyond?

For 2010, NPDES permits are only required in the states of California, Washington and Oregon. Please check with your local NPDES permitting offices to determine what each state requires.

For 2011 and beyond, the U.S. EPA is developing an NPDES permit that is to be implemented in all states by April 10, 2011. More information will be provided as EPA progresses in the development of this permit.
For more information, contact Dale Carpenter at 208-860-1867 or email dale.carpenter@uniphos.com, or call the UPI toll-free number at 800-438-6071.