Cody J. Gray, Ph.D.Field Development, Aquatics Specialist

United Phosphorus, Inc.

Approval of New Labels for Aquathol and Hydrothol

Label Updates

• No fishing restrictions

• No swimming restrictions

• No restrictions on irrigating food crops

• No restrictions on irrigating non-food crops (lawns, landscaped areas, golf courses, etc.)

Irrigation Restrictions

• No supplemental label will be issued addressing the removal of the irrigation restrictions.

• Must have new product with the new labels!!!

New 2010 Products

• Introducing two new products for use in irrigation canals…

– Cascade Aquatic Herbicide

– Teton Aquatic Algicide and Herbicide

The Difference

• Cascade– Vascular plant herbicide– Will not directly control algae, but will have

an indirect effect

• Teton– Vascular plant herbicide and algicide– Will control algae at 0.15-0.3 ppm

Laboratory Studies Conducted

Results:

- Sago Pondweed susceptible to endothall

1.0 ppm / 24 hrs2.0 ppm / 12 hrs3.0 ppm / 8 hrs

- Effective in cool water temperatures 55 to 65o F

Can vary water quality

Common Symptomology

4 WAT 8 WAT

5 DAT0 DAT

14 DAT 35 DAT

2007 & 2008 Small-Scale Research Canals

Treated: June 10, 2008 2 ppm for 8 hrs

28 Days After Treatment

Jerome, ID 2008

Canal was weed-free for 16 WAT

2009 Greeley, CO

0 DAT 17 DAT40 cfs treated at 3 ppm for 8 hrs

9 miles from application site

Twin Falls, ID – Section 18 Endothall Application 6/16/09

• Planned an 8 hour injection at 3 ppm endothall in the main canal ~ 1900 CFS– 12 hour injection closer to 2 ppm

• Research questions:– How far will phytotoxic residues move?– Will the treatment move through the system in a large

block or will it become too diluted?– Does endothall penetrate dense plant beds?

• Channels?– Efficacy

• Water temperatures ranged from 56 to 64o F

Application Equipment

Initial SamplingInjection site – 0700 – 2000 hrs (13 hr)Forks 9 miles

Measured between 2 and 3 ppm at Forks (1500 to 0500 hrs)

-No appreciable loss of product

-At forks – canal splitInto hi-line & lo-line

Day 1 – Target residues ~15 mi. downsteam

Day 2 - Additional Drip Stations• Due to uncertainties with this first large-scale

treatment– Additional treatment stations were placed on the

Hi Line & Lo Line to add 1.0 ppm endothall from 0100 to 1300 hrs

• Result: Downstream residues ranged from 2.6 to 3.4 ppm up to 25 miles from the forks– 34 miles from the original drip station– Extra stations increased the conc. by ~1.0 ppm– Concentrations in laterals = main canals

Additional application sites

Day 2 Sampling

• Complete clearance of endothall at ~18 miles past the injection site (0800 hrs)

• Fairly distinct head and tail of the treatment plume was noted– ~18 mile area with endothall between 2 & 3.7 ppm– A leading edge of ~1 mile with lower endothall

residues was detected (0.3 to 1.2 ppm)

Endothall levels heldsteady at 35 miles past the injection site.

No loss of endothall as water passed through the power stations

Endothall penetrated dense Sago beds

Day 2 Summary

Day 3 Sampling• Detected endothall at

tail end of Lateral 2– 3.0 ppm at 63 miles from

the initial injection point• Detected endothall at

tail end of Lateral 5A– 2.4 ppm at 67 miles from

the initial injection point• Very limited

degradation and the treatment block remained largely intact– No large head or tail

Lateral 17 Canal13 Miles from Initial Injection

Day of Treatment

Lateral 17 Canal13 Miles from Initial Injection

21 Days After Treatment

Low-Line Canal45 Miles from Initial Injection

Day of Treatment

Low-Line Canal45 Miles from Initial Injection

7 Days After Treatment

Low-Line Canal45 Miles from Initial Injection

14 Days After Treatment

Low-Line Canal45 Miles from Initial Injection

21 Days After Treatment

Detweiler Pond28 Miles from Initial Injection

Day of Treatment

Detweiler Pond28 Miles from Initial Injection

8 Weeks After Treatment

Efficacy Summary

• 8-10 weeks after treatment (WAT)– control was >90-95% throughout system

• 12-13 WAT– control was 80-85% throughout system

• 15-16 WAT (season-long)– control was 70-75% throughout system

• Did notice horned pondweed emergence about 8-10 WAT, but did not interfere with flow

Cascade Results• Some locations may require 2 apps/yr

• No crop or fish complaints because of treatment

• Greater than 1,000 total miles of canal controlled

• Some minor touch ups were needed in shallow water (1-3 ft)

Summary• The endothall injection resulted in treatment

of essentially the entire TFCC system

• Cooler water limited degradation of endothall

• Product remained in a fairly defined treatment block (no significant head or tail)

• Endothall penetrated dense plant beds and saw no degradation through power plants

Teton Application

11 Weeks after Treatment

2 ppm a.e. Teton @ 8 hrs

Cascade + Teton Application0.85 ppm a.i. Cascade + 0.15 ppm a.e. Teton

11 Weeks after Treatment

AcknowledgmentsU.S. Army Corps of Engineers

Dr. Mike Netherland Jeremy Slade

Twin Falls Canal CompanyBrian Olmstead

North Side Canal CompanyLarry Pennington

Questions?