February 5, 2007

SPRAY BULLETIN

The 2007 Virginia/West Virginia/ Maryland Spray Bulletin For Commercial Tree Fruit Growers will be available by mid-February, however, the cost is yet to be determined. Contact the WVU-KTFREC at 304-876-6353, or at Libby.Nester@mail.wvu.edu after mid-February to determine availability and cost.

ENTOMOLOGY

Phase-out of azinphos-methyl (Guthion) on the remaining tree fruit crops was announced by EPA on November 17, 2006. Season maximum use reductions will occur over the next 6 years (Table 1), with no use after September 30, 2012. New buffer zone and "pick-your-own"/"U-pick" restrictions go into effect immediately.  Application is prohibited within 60 ft of permanent bodies of water and within 60 ft of occupied dwellings (does not include farm buildings). All aerial application is prohibited. Applications are prohibited on cherries for "pick-your-own"/"U-pick" harvesting. For apples and pears, the preharvest interval (PHI) for "pick-your-own"/"U-pick" harvesting is 44 days for application rates of 2.02-3 lbs. formulated product/acre; 39 days for application rates of 1.22-2 lbs. formulated product/acre; and 33 days for rates less than 1.22 lbs. formulated product/acre. Use on peaches and nectarines ended on September 30, 2006. For additional information go to http://www.regulations.gov -- AZM docket number EPA-HQ-OPP-2005-0061.

Table 1.  Season use limit of azinphos-methyl (Guthion) on tree fruits.
 

Imidan reregistration decisions were issued by EPA on January 19, 2007 regarding uses on fruit crops. The EPA determined that most restricted-entry intervals (REIs) will be lengthened and additional risk mitigation will be implemented to protect workers. Additional mitigation includes lower seasonal maximum application rates, prohibition of Imidan application until after certain high-exposure activities have occurred, a 25-foot buffer zone around occupied dwellings for ground applications, a 50-foot buffer zone around occupied dwellings for aerial applications, and health protective entry restrictions for pick-your-own operations.  Additional biomonitoring or other data is also required to address remaining uncertainties in the existing database. These changes are to be included on product labels sold or distributed by the registrant after June, 2008 (see Table 2 for significant changes). For more information go to at http://www.regulations.gov -- phosmet (Imidan) docket number EPA-HQ-OPP-2002-0354.

Table 2.  Imidan restrictions on fruit crops after June, 2008.
 

^aFor 70W formulation.
^bEast of the Rockies.
^cSame as current label.

PLANT PATHOLOGY

Peach leaf curl should be controlled in the spring with a fungicide application before the buds swell, unless you already made a leaf curl application in the fall. If leaf curl was severe in your peach and nectarine blocks in 2006, and you made your fall fungicide application to control the disease for 2007, a spring fungicide application may be needed to ensure complete disease control. In orchards where careful monitoring is practiced and where leaf curl has not been present for two or more years, this spray can be omitted until the disease begins to recur. For best control of peach leaf curl, make a dilute application of fungicide under calm conditions, making sure to cover each bud thoroughly. Using one of the fixed coppers for the leaf curl spray may help suppress bacterial spot in blocks where this disease is a problem. See the Spray Bulletin for fungicides and rates of application.

Apple scab urea application. A spray of 5% solution of urea (46-0-0) in water may be applied to apple leaves on the ground if this was not done in the autumn (42 lb. urea in 100 gal. water, applied at 100 gallons/acre). The nitrogen will hasten leaf litter decomposition and may result in reduced inoculum from the apple scab fungus. Moving leaves from under the trees to the row middles with a leaf blower and then shredding them with a flail mower is a good alternative to the urea spray for small acreages.