Fruit IPM for 8/10/19

Blueberry

A Rare Tme for the Stars to Align: Sharpnosed leafhopper adults are flying, and scale crawlers are emerging.

While we may yet see an increase in the adult SNLH flight, sufficient adults are present to merit treatment. Putnam Scale crawlers are also present, and should be treated now in fields which had marked berries in the first generation.  We usually see scale crawlers first, and then need to treat for SNLH adults about 2 weeks later. This is the first time, (in 30 years) I have seen the timing line up. Therefore if you are using Diazinon for treating scale (it controls both SNLH and scale), then you can probably put the sprayer away after that treatment. If you are not treating for scale then you are free to use other materials for SNLH control, such as Actara, Assail, Admire, or Imidan. For scale treatments: Target a 50 gal per acre volume. Do Not make this treatment by air! This is not a flying insect, but instead a very small crawling stage that stays on the wood. Therefore the entire cane should be covered. The primary treatment window should last for about another 10 days.

Blueberry Traps

Atlantic County Traps

Burlington County Traps

Peach:

Oriental Fruit Moth: All degree day timed treatments for the 3^rd flight are over statewide. This is the time of year when the later generations (generation 3 and 4) can start to overlap. This combined with reproduction in recently harvested blocks, but no longer sprayed, can help lead to higher populations. From now through the rest of the season OFM treatment decisions should be made on the basis of trap counts. If trap captures exceed 6 moths per trap, then treatments are justified. For the second week in a row, southern orchards are showing very high populations, so should continue to be treated. The trap count average in northern counties are quite a bit less, but still exceeds the treatment threshold on some farms.

Brown Rot: Most growers should be relying on a captan based program for mid-season covers, followed by better materials during the last 3 weeks pre harvest. Do not spray captan or sulfur if temperatures are above 85-90 deg F. and do not combine captan with sulfur in hot weather with poor drying conditions. See Dr. Norm Lalancette’s recent article in the Plant and Pest advisory for more information on pre harvest brown rot programs.

Apple:

Rots/Summer Diseases: Summer diseases, particularly bitter rot, are the primary diseases of concern. See last week’s newsletter for a summary of treatments, and ongoing research at Penn State in Biglerville.

Codling Moth (CM) and Options for Internal Worm Control: Trap captures on most farms are below the treatment threshold of 5 males/ trap/ week. Although some locations show populations above 6-18 moths per trap, particularly in northern counties. The timing table below is for general guidance only. At this time of year growers should pay more attention to trap counts than the degree day model. Some locations have codling populations that have started early and may continue to be drawn out, emerging over a prolonged time period. Where growers have had trouble in the recent past controlling codling moth, and are not using mating disruption, then think about supplementing weekly applications of Madex along with Altacor, Voliam or Delegate applications. Make sure you are well calibrated, and that you are delivering sufficient spray volume to penetrate the tree foliage. Growers in northern counties may wish to insert 1 application of Rimon or Intrepid as one of the treatments made around 8/18-19.

Brown Marmorated Stink Bug (BMSB): Populations are starting to show up, mostly in some North Jersey orchards. Most pyrethroids like Baythroid ( 7 day PHI), Danitol (14 day PHI), and Mustang Maxx (14 day PHI) work well. Belay (7 day PHI) is also effective, along with several premixes. Be aware of the PHI’s especially with early varieties. Note that the PHI is often different for peaches than it is for apples.

Grapes:

Veraison timing is important for disease control. See a recent blogpost from Dr. Nita at Virginia Tech for more information. Additional information on mid and late summer disease control from Bryan Hed at Penn State is also linked here.

Grape Berry Moth (GBM): The next treatment for IGR’s timing in southern counties is on or about 8/10. Conventional insecticides can be applied a few days later.

Grape Trap Counts

Tree  Fruit Trap Counts – Southern Counties

Tree  Fruit Trap Counts – Northern Counties