Fruit IPM for 07/08/21

Blueberries:           

Blueberry Maggot (BBM): No blueberry maggot adults were found last week. However, the first fly was caught on Tuesday July 6 in Hammonton.

This is about 1 month later than “normal”. A second adult was captured on Wednesday, July 7. Both captures were in already harvested Duke fields where spraying had stopped. Positive traps were by the woods in the corners of the fields where it is difficult to cover by air. This means that growers who are exporting to Canada should be covering with a BBM effective insecticide within 5 days of that first capture.

Aphids:  Aphids are still being found, but in decreasing numbers.  The average shoot infestation is 6.07% with a high of 58% of shoots infested.

Spotted Wing Drosophila (SWD): Populations have increased dramatically over the past week, as indicated by trap counts and population pressure. Larval infestation pressure has significantly increased. Reapplications are necessary if insecticide has been applied, only to be washed off in a thunderstorm. Make sure to target the bottom half of the bush as well as berries dropped on the ground, in addition to the tops of the plants. Adult flies are the most active during the early morning hours and at dusk. Therefore, applications of insecticide during the very early morning hours and twilight will be more effective than if applied during late morning to mid-day.

By the Numbers Summary:

Peach:

Oriental Fruit Moth: On most farms we are between generations and no targeted insecticides are required. Insecticides will only be needed if the OFM trap count exceeds 8 moths per trap.

Thrips: Thrips are present in poorly managed groundcovers in southern counties and some slight damage has been noted. Delegate has a short PHI and is effective at the high rate. Lannate may work in some orchards.

 Brown Rot: Disease pressure is still present and will increase with tropical storm downpours predicted for later this week. See last week’s newsletter and the 2021 Tree Fruit Production Guide. Also from the previous newsletter: About 10 weeks before anticipated harvest begins, use captan at 3 1/8 pounds per acre in cover sprays; at 3 weeks prior to harvest use Flint Extra at 3.8 ounces acre; and then follow the usual preharvest schedule with Fontelis at 16-20 ounces 2 weeks before harvest and Inspire Super or a propiconazole product at 1-4 days before harvest.

Apple:

Codling Moth (CM): On average, trap captures are low, but we should start to see an increase as the second flight starts to emerge. Given how this insect can be problematic on some farms, it is very important to hit the second emergence on time. Approximate timings for the initial 2^nd generation treatments are outlined below:

Tufted Apple Budmoth (TABM): Trap counts indicate that this is the end of the first generation flight. No treatments are usually needed during July, even on farms with high populations.

Summer Diseases: Rots are now appearing in susceptible varieties. Bitter rot is of most concern but white rot has also been seen in some varieties. Cover sprays with Captan at 3.5#/acre plus a phosphorus acid product may help to suppress further rot infections and will improve sooty blotch and fly speck control.

Grapes:

Spotted Lanternfly: Adults will start to appear over the next couple of weeks. Adults can aggregate in the vineyard, producing very high population which will need to be controlled.

Japanese Beetles: June into July is typically the time when Japanese beetles emerge. They will soon be feeding in the canopy. Insecticides effective for Japanese beetle management include Sevin and Imidan, formulations containing imidacloprid such as admire pro and leverage, other newer generation neonicotinoids and Avaunt, as well as most pyrethroids. The following table is from the Virginia 2021 Production Guide:

 Diseases: Downy mildew is appearing in southern county vineyards as spring diseases like phomopsis and black rot are nearing the end of the target window. As we enter the summer period of disease management the focus broadens to cultural controls along with well-timed fungicide applications for downy mildew and powdery mildew management. Horticultural practices to improve fruit quality such as shoot positioning, hedging, and leaf pulling also allow for quicker drying and better pesticide penetration in the canopy and fruiting zone. See Dr. Nita’s recent presentation from Virginia Tech covering summer disease management and Penn State’s leaf pulling webinar for more information.

Scouting Calendar Tree Fruit Southern Counties

The following table is intended as an aid for orchard scouting. I t 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