Fruit Pest News
Volume 7, No. 2 March 22, 2006
A weekly, online newsletter whose goal is to update Extension agents and growers of commercial tree fruit and small fruit crops
on diseases and insects in Tennessee.
Text appearing in blue or red can be clicked to link to other web sites. Be aware that much of the linked information is produced in other states and may not be applicable to Tennessee.
In This Issue:
1. Current Conditions
2. Fruit Pesticide Recommendation Changes
3. Dormant and Delayed Dormant Oil Sprays and Other Scale Controls
4. Pheromone Trap Time Again
5. Coppers Targeted by EPA (tiime-sensitive information)
1. Current Conditions
Well, the first day of spring brought a return to winter weather. Days will be cool for the next week, and lows will be in the upper 20's to low 30's for the next several nights. Apple trees are not yet in bloom, but peaches are in full bloom. Fruit plants have made little advancement since the last issue. However, I have a report of copious spore production by cedar-hawthorne rust galls on cedar trees in Memphis. This is the rust that forms the narrow orange galls along the stems, not the spherical ones. The lady indicated that she had been slimed. She had not yet seen cedar-apple rust galls, and Memphis is ahead of much of the state, but apple growers should be preparing to apply their rust sprays when the ground dries out enough. Scale insects were a big story last year, so I hope everyone got their oil sprays out while their scale-prone trees and bushes were dormant. (SB)
2. Fruit Pesticide Update
There were several additions to the 2006 Southeastern
Peach, Nectarine and Plum Pest Management and Culture Guide. Last year or so the
pyrethroid, gamma cyhalothrin (Proaxis 0.5 EC) was added. This year, a couple other
lambda cyhalothrin insecticides (Lambda-T 1EC and Silencer 1EC) were added. They
are primarily for plant bug and Oriental fruit moth control.
Azinphos-methyl
(Guthion, Sniper) group 2 uses were terminated effective August 2005 for peaches,
nectarines, cranberry, caneberries, potatoes and several other crops. The distribution
or sale of existing stocks of end-user products will be extended to March 31, 2006
on the above mentioned crops. September 30, 2006 is the proposed stop use date for
existing stocks.
Cyfluthrin (Baythroid 2) and B-cyfluthrin (Baythroid XL)
has new fruit uses on the label including use on apples and pears (7 day pre-harvest
interval [PHI]); peaches, cherries, and plum (7 day PHI); and grapes (3 day PHI).
Acetamiprid (Assail 70 WP) is a new insecticide in the neonicotinoid chemical
class labeled for use on pome fruit. when sprayed on the foliage, it has translaminar
activity (moves across the leaf from the sprayed side to the unsprayed side). It
is also rainfast once the spray has dried. Assail is labeled for control of aphids,
tentiform leafminer, leafhoppers, codling moth, mealybug, and psylla. Assail should
not be applied more than four times per season nor applied more than once every 12
days. The PHI is 7 days. (FH)
3. Dormant and Delayed Dormant Oil Sprays
and Other Scale Controls
We continue to stress the importance of using superior
oil as Dormant and Delayed Dormant sprays because they are relatively inexpensive
and quite effective. Higher rates provide an incremental improvement in control,
but two applications typically outperform a single, high rate application. Temperatures
that are consistently cool are optimal for oil application. Avoid spraying when
temperatures are to drop near freezing or are expected to be unseasonably warm.
On peach, nectarine or plum, do not use oil after 5% pink bud. If scale
has been a problem on stone fruit, another option in addition to oil is the use of
pyriproxifen (Esteem 35 WP) later on (7 to 10 days after shuck split through the
cover sprays). Wrap double sided Scotch tape around an infested twig or make a crawler
trap by wrapping the twig with black electrical tape and then coat with a thin layer
of petroleum jelly. When the crawlers emerge and are caught, treat with the Esteem
35 WP. Post-harvest scale control can be used to target crawlers, when present,
with Diazinon AG-500 (3 pints/acre) as a dilute spray or all season horticultural
oil (Saf-T-cide) as a dilute spray at 1 to 1.5% by volume (do not apply within 2
weeks of applying sulfur, captan or Sevin). Do not apply all season horticultural
oil if temperatures reach the high 90s.
Scale crawlers readily move from
infested plants to adjacent orchards. Hedgerows with abundant privet are a problem.
Where possible, push out scale-infested adjacent vegetation.
In addition
to oil sprays for San Jose scale in apple, apply an insecticide such as Dimethoate
4E/400, Diazinon 50 WP, Guthion 50 WP, Esteem 0.86 EC, or all season horticultural
oil for first generation crawlers (look for them from petal fall through third cover).
Diazinon or all season horticultural oil applied with captan may cause
phytotoxicity.
The pyrethroid insecticides Asana XL and Ambush will not
help control mites or scales. Also, if you are having scale problems, avoid using
pyrethroid insecticides during the growing season, because they can kill scale predators
and parasitoids that normally would help manage scale populations. There are new
insecticides and miticides available for tree fruit, but why not first try to get
all you can out of the oil sprays. (FH)
4. Pheromone Trap Time Again
Pheromone
traps have been mailed to our cooperators. On March 1, I put out a new redbanded
leafroller (RBLR), Oriental fruit moth (OFM), and variegated leafroller (VLR) traps
with fresh pheromone at the Ellington Agricultural Center in Nashville. There were
3
RBLR moths in the trap by the next day. Warm night temperatures got the moths flying.
The other pheromone traps will be put out soon. (FH)
5. Coppers Targeted by EPA
If you haven't heard about the EPA's re-registration process for coppers currently taking place, we are in the public comment period now, and comments are due by Monday, March 27. Copper products are extremely valuable for fruit and vegetable production in Tennessee. If coppers are valuable to your operation, you should let the EPA know how you feel about the threat to this valuable production tool.
The main concern with copper seems to be with its impact on aquatic organisms. Spray drift into ponds and streams is the primary means of environmental impact, although accumulation in soil is also considered a threat. The summary document provides more information: http://newsletters.caes.uga.edu/SRPN/6-1/EFED_Copper_Risk_Summary.pdf .
This link, http://newsletters.caes.uga.edu/SRPN/6-1/Copper_Risk_Assessment_Example_Letter.doc , contains a sample letter that you can use, but it would be more effective to tell, in your own words, what the coppers mean to your operation. Of most importance are the target diseases for which you use the coppers, and the amount of loss you would expect if you didn't have access to the effective rates of copper. After the comment period, EPA will begin the process of negotiating risk mitigation with the task force. These methods may include reduced rates and number of applications, and when the sprays can be applied.
In Tennessee, some of the crops that depend heavily on coppers are peaches (bacterial spot, leaf curl), tomatoes (bacterial spot, speck, and canker), peppers (bacterial spot), apples (fire blight), cucurbits (angular leaf spot, bacteria spot), and strawberries (angular leaf spot). When used for these target diseases, coppers also provide some control of other troublesome diseases (e.g. downy and powdery mildew of cucurbits). As a broad spectrum disease control agent, copper functions as a resistance management tool by discouraging resistance to the many specialized fungicides in use today.
To mail your letter, use this address:
Public Information and Records Integrity Branch (PIRIB)
Office of Pesticide Programs (OPP) (7502C)U.S. Environmental Protection Agency
Ariel Rios Building1200 Pennsylvania Avenue, N.W.
Washington, D.C. 20460-0001
Inside, use this to identify your letter:
Attention: Docket ID Number EPA-HQ-OPP-2005-0558
Re: Copper Pesticide Risk Assessments
To email your comments:
opp_docket@epa.gov
To use the docket system (preferred):
Go to www.regulations.gov and use the Docket ID: EPA-HQ-OPP-2005-0558. Please copy: louie.rosanna@epa.gov
(SB)
The Fruit Pest News URL is: http://web.utk.edu/~extepp/fpn/fpn.htm
Contacts:
Steve Bost, Professor and Extension Plant Pathologist
Frank Hale, Professor and Extension Entomologist
Both authors available at:
615-832-6802
fax 615-781-2568
Plant and Pest Diagnostic Center
5201 Marchant Drive
Nashville, TN 37211
Copyright 2006 The University of Tennessee. All rights reserved. This document may be reproduced and distributed for nonprofit educational purposes provided that credit is given to University of Tennessee Extension.
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