Tree Fruit IPM Report for August 18, 2022

Peach:

Oriental Fruit Moth: A biofix point for OFM was set on 4/11 in southern counties, and on 4/14 in northern counties. The third generation timings are are over in all regions. Additional treatments should be made if trap captures are over 6 moths per trap.

Scale Insects: White Peach Scale crawler emergence has ended for this generation. San Jose Scale Crawler emergence is past peak and declining. White Peach scale has a third generation in September and San Jose scale may have a third generation in October. Options at this point include: Assail, Belay (Group 4A); and the bioinsecticide Venerate. These products may provide some late season suppression where fruit damage is observed. Only Venerate has a 0 day PHI, making it useful for blocks near or at harvest.

Apples and Pears:

Diseases: Summer scab, rots and sooty blotch and fly speck are the main targets at this stage. Where scab is present rely primarily on protectant fungicides. Last year Captan plus a phosphorous acid like Prophyt was observed to slow scab development as well as provide good summer disease control. Merivon and Luna Sensation are good materials to use close to harvest. thaey are very effective for summer diseases and leave little residue.

Brown Marmorated Stink Bugs: Brown Marmorated Stink bugs are present at low to moderate levels in orchards statewide. See the NJ Tree Fruit Production guide for effective materials.

Codling Moth (CM): Timings for the second generation are updated below.  A biofix was set for CM on April 25^th in southern counties, and May 6 in Northern counties (Middlesex County). Second generation treatments according to the degree day model are now over. Additional treatments should be made if trap captures are over 5 moths/trap. Some orchards have had continuing trap captures above threshold.

Scale Insects: For San Jose scale see the peach section above.

Grape

Bunch Rots: Grapes are beginning veraison in southern counties. Disease management continues to focus on downy and powdery mildew and and now also turns to bunch rot management. Refer to the NJ Commercial Grape Production Guide as well as the linked presentation from Dr. Nita in Virginia. Additional information can be found in this linked presentation from Dr. Bryan Hed at Penn Sate.

Grape Berry Moth: The timing for the third generation is past. In some hot summers a fourth generation may occur, however no further treatments should be needed, especially where insecticides are being applied for SLF.

Spotted Lantern Fly: Spotted lantern fly adults are now appearing in vineyards. At this stage border treatments with effective materials should be adequate since most adults will be found on vineyard edges and populations will be low. As we move into September adult migration will increase and at that point growers should apply materials with long residual efficacy (refer to the table from Penn Sate below.) More information on biology and control can be found from Penn State.

Drosophilds and Sour Rot: SWD adults are being caught in and around commercial vineyards. As the sugars start to increase in early verities like Chardonnay, be aware of Spotted Wing Drosophila combined with native fruit fly species. These populations increase at this time of year and help spread sour rot. Sour rot will only be present when you also have injured fruit. Fruit splits and various insects can help cause that initial injury. It is thought that the spotted wing drosophila (SWD), because of its saw-like ovipositor, can help cause this initial injury, helping to make the fruit more attractive to native drosophilid species.  After injury the fruit serves as a food source for ethanol-producing yeasts and acetic acid producing bacteria, the causal agents of sour rot. This in turn attracts more fruit flies to lay more eggs and spread the decay. Good canopy management for air circulation is useful to reduce sour rot incidence. However, this must be combined with insecticides and antimicrobials. A treatment regime that consists of weekly applications of an insecticide (Mustang Maxx (or other pyrethroid), Malathion, Delegate/Entrust, Verdepryn).  Add Oxidate 2.0 if fruit cracking from rain or other causes is observed. Since it is important to rotate insecticide classes when treating this often, growers should use no pyrethroid or other insecticide class more that 2 times in a row. These treatments should be started before the onset of visible sour rot and fruit fly presence.

Tree  Fruit Trap Counts – Southern Counties

Tree  Fruit Trap Counts – Northern Counties