Malathion Use on Almonds in California
Date: March 9, 2006
To: Teung Chin
Office of Pest Management Policy
USDA
From: Gabriele Ludwig
Almond Board of California
Teung,
Many thanks for providing a heads up on malathion reregistration issues. Very little malathion is used in the almond industry. For the last 4 years the usage has been less than 100 A out of 550,000 + acres. Actually I can't find any usage in the 2004 PUR. I have not heard malathion described as a tool of last resort or as an alternative for certain insect problems in almonds. Thus, at this time any changes would not be a big deal for the almond growers.
Gabriele
Gabriele Ludwig, Ph.D.
Senior Manager, Global Technical & Regulatory
Affairs
Almond Board
of California
Tel: 209-765-0578
gludwig@almondboard.com
From: Teung.F.Chin@aphis.usda.gov [mailto:Teung.F.Chin@aphis.usda.gov]
Sent: Thursday, March 09, 2006 10:31 AM
To: ldlindsay@prodigy.net; Gabriele Ludwig; Steve Toth; jess@msu.edu
Cc: rsmelnicoe@ucdavis.edu; Jim_VanKirk@ncsu.edu; Allen.Jennings@usda.gov; olsenl@msu.edu
Subject: Malathion Use on Walnuts, Pecans and Almonds
Dear Duane:
To reduce calculated drinking water risk estimates, EPA is reviewing the use of malathion on walnuts. The current maximum Cheminova-supported rate is 2.5 lb a.i./A x 3 applications x 7 day retreatment interval.
However, EPA believes the typical application rate is 3.8 lb ai/A x 1 application up to 6 lb a.i./A x 1 application. Applications have been made as high as 8 lb ai/A.
EPA has asked growers to consider as a risk mitigation measure: that all future labels will have a new maximum of 2.5 lb ai/A x 3 applications x 7 day retreatment interval.
The residue data for walnuts is supportive of malathion use on pecans and almonds. Could pecan and walnut growers also comment on if they can accept the EPA-proposed new maximum? IF not, what maximum label rate is needed and why?
If EPA's new maximum application rate is a problem for walnut, almond and pecan growers, we will need to see if another registrant or IR-4 will undertake residue studies to support higher application rates of 3.8 lb ai/A to 8 lb ai/A. We would also see if any further refinements can be made to the EPA drinking water risk assessment.
Please let me know your thoughts in two weeks. EPA is slowly working its way through a list of 20 crops with the highest usage of malathion. Then we go onto Group 2 and Group 3.
Thanks again for your assistance:
Please do not hesitate to contact me if you have any questions or comments.
Best regards,
Teung
Teung F. Chin, Ph.D.
Biological Scientist
Office of Pest Management Policy
Agricultural Research Service
United States Department of Agriculture
LOCATED AT:
USDA Animal & Plant Health Inspection Service
4700 River Road, Unit
149 (Room 3D-06.8)
Riverdale, MD 20737-1237
Phone (301) 734-8943
Fax (301) 734-5992
Teung.F.Chin@usda.gov
http://www.ars.usda.gov/opmp
