Fruit IPM for August 12, 2020

Peach:

Stink Bugs Apples and Peaches: BMSB populations are generally low and little changed since last week. However, hatching egg masses are present statewide. Therefore populations can increase in the near future. As the peach season comes to a close, BMSB has the potential to be more of a problem in apples.Oriental Fruit Moth (OFM): We are at the treatment timing for the third generation, but there is little to no pest pressure in southern counties. In northern counties populations are more evident. Treatments are justified if there are over 8 moths per trap. The updated timings for average pressure areas is below:

Scale Insects: Both White Peach Scale and San Jose Scale second generation crawlers are still active. In some orchards, the crawlers have settled on peach fruit, which of course downgrades the fruit. More importantly, it is an indicator of high populations which need to be treated. Centaur WDG @ 34.5 oz/A has a 14 day PHI on peach, apple and pear. Esteem 35WP @ 5 oz/A has a 14 day PHI on peach, but a 45 day PHI on apple and pear. Diazinon (50W) can also be used against the crawler stage @ 1-2 lb/A with a 21 day PHI for peach, apple and pear. Only 1 post-bloom application is allowed per year. Any scale application should be applied as dilute as possible, but not to run-off. Esteem and Diazinon will also help with codling moth control in apples, but should not be relied upon as the sole control tactic in problem blocks.

Apple:

Codling Moth (CM): Trap captures increased significantly last week in Southern Counties and additional egg hatch appears to have started recently as stings have been noted on treated blocks. Treatments should be continued any time there are close to 5 or more moths per trap. Diamide products (Altacor, Voliam, Besiege, Exirel, Verdepryn), and Delegate are the products of choice. Under high populations, the additional use of the CM/OFM virus, Madex, can be helpful.

Rots (reprinted from last newsletter): Various rots, mostly bitter rot are still appearing in some orchards. Bitter rot infections will continue during wetting periods for the rest of the summer.  The Qol premixes Merivon and Pristine are good rot materials with Merivon being the better of the two. Luna Sensation and Luna Tranquility are also rated as effective. Alternate with a Captan/Prophyt mix or Captan/Topsin. Topsin has some efficacy for white and black rots but is not effective against bitter rot.

Grapes:

Grape Berry Moth (GBM): While we are approaching the model timing for treating the 4^th generation, the precise ability to time sprays with the model starts to fall apart late in the season. According to both recorded and predicted degree day accumulations, we should hit the 4^th generation timing in southern counties about 8/22-24. However, you may notice that the Cornell NEWA site has a cautionary statement concerning late season applications for GBM. It states: “If 1620 DD occurs prior to August 5, you can expect continuous pressure from grape berry moth through harvest. Model results are not good predictors of timing of population pressure.” Dr. Greg Loeb (Cornell) indicates that this may be partly due to an unknown diapause length late in the season, prolonged egg laying, and possibly overlapping late-season generations. While we seldom experience the severe late season GBM problems that some producers experience in the Finger Lakes, this is a word of caution that regular scouting, especially along borders can be important at this time of year.

Spotted Lanternfly (SLF): From now through September, we expect to see increasing levels of adults in vineyards, especially from central to northern counties, although SLF is also present in southern counties. SLF adults will commonly settle on the edge rows nearest a wooded border, and these are the areas which may get the highest populations. If you wish to treat for high populations of SLF adults, the following materials can be used in grapes (adapted from Penn State). Other formulations may be available, but the data was generated with the formulations listed.

Scouting Calendar Tree Fruit Southern Counties

The following table is intended as an aid for orchard scouting. It should not be used to time pesticide applications. Median dates for pest events and crop phenology are displayed. These dates are compiled from observations made since 1995 in Gloucester County. Events in northern New Jersey should occur 7-10 days later.

Tree  Fruit Trap Counts – Southern Counties

Tree  Fruit Trap Counts – Northern Counties

Blueberry:

Spotted Wing Drosophila (SWD) : This is the only pest of concern, and only on the latest varieties. The average Elliott field may require only 1 more treatment.

Putnam Scale: Tape traps were set out in a number of fields with known 1^st generation populations that had settled on the fruit during July. We have now detected second generation crawlers on 7 of the 10 traps set. The number of crawlers seen on positive traps range from just a few to a maximum of 57 crawlers per trap. Higher numbers are present in Atlantic County compared to Burlington County. Recall that Putnam Scale has 2 generations per year, with the young crawlers emerging 2 times per season. The first emergence starts during the first half of June, and the second , during the first half of August. As the crawlers disperse from the ‘mothers’, they move up the canes and can reach the fruit if the populations are high enough. This means that any fields that produced scale infested fruit in July have populations now that are high enough to be treated. Options for control include: Esteem 35W @ 5oz/A, or Diazinon @ 1-2 lb/A (50W). The diazinon label specifies that there is a maximum of 2 lb of formulated product allowed per season, and a maximum of only 1 in-season foliar application per year. In most cases this will be a post-harvest application, but there is 7 day PHI for diazinon. The application volume is just, if not more important that the rate. The insecticide must contact the insect as it crawls up the cane and onto the branches. Make sure to use as much water as possible, or close to 50 gal/A. Scale applications Will Not Work if done by air. Good pruning that eliminates the old canes that harbor the highest populations is another management tactic that should always be practiced.

Sharpnosed Leafhopper (SNLH): Adult populations remain very low, indicating that 2^nd generation adults have not yet matured or started to move about. It is too early for any insecticides directed against SNLH.