Fruit IPM for 6/22/21

Peach:

Oriental Fruit Moth: Growers who have used mating disruption for OFM should continue to focus on PC; GPA; and catfacing insect pests as described below. For those growers using insecticides, the first of 2 applications in northern counties is due this week, and the second of 2 applications in southern counties is due next week. This is particularly important where the moth flight is exceeding the treatment threshold of 8 moths per trap.

Catfacing insects (true bugs – tarnished plant bugs and native stink bugs): Populations of tarnished plant bugs and other ‘catfacing insects’ are high where weeds are present. Damage exceeds 2-3% injured fruit in some northern county locations. This is THE reason why we encourage pure grass groundcovers. See the 2021 TFPG for suggested materials. Weedy groundcovers will also influence thrips populations –

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: Inoculum is building on blocks with high amounts of constriction canker and in blocks where thinning operations broke fruiting branches or did not completely remove thinned fruit. Fruit that has stopped growing and remained on the tree is being infected with brown rot and is building inoculum for later in the season. Conversations with Dr. Lalancette yielded the following optimum recommendations for growers who are seeing brown rot already in their orchards: 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.

Bacterial Spot: Maintain tight covers with antibiotics until pit hardening. Typical antibiotics used include various copper and oxytetracycline formulations. Full covers with at least 100 gpa are recommended around wetting periods or severe weather. Some bacterial spot is present in northern counties, and is present in most blocks of highly susceptible varieties in southern counties.

Cherry:

Spotted Wing Drosophila (SWD): For those growers with cherries, protection is still needed from SWD. Effective insecticides for use on cherries include Asana, Baythroid, Cormoran, Danitol, Delegate, Entrust, Exirel, Imidan, Lambda-Cy/Warrior, Mustang Maxx, Malathion, and Verdepryn. Check the 2021Tree Fruit Production Guide for PHI’s and REI’s. For those growers who have been on a regular program and still wish for a “0” day PHI program. The use of GF-120 (same ai as in Entrust) applied to the trunks (waist down) with a large droplet, low pressure hand-gun may be an option. A final alternation with Grandevo WDG may also help. Both products will only give about 3 days of activity and can only be used in low pressure environments.

Apple:

Tufted Apple Budmoth (TABM): Trap counts indicate population increases in several northern county orchards. This is a pest that was a serious tree fruit problem more that 25 years ago when it developed resistance to organophosphate insecticides. At that time, we noticed damaged fruit in areas where trap counts exceeded 40 moths per trap, mostly from the second generation in August.  We are presently in the first of 2 generations and are seeing over 100 moths per trap in 3 northern county locations. While it is too early to speculate why we are seeing this, growers should always rotate chemistries, and with TABM, alternate middle treatments are required about every 7 days through June.

Woolly Apple Aphids (WAA): Small WAA colonies are present in several northern county orchards. WAA also produces colonies on the root system, which under heavy populations, can stress the tree. These aphids should be controlled before colonies get too dense and numerous. One of the best controls at this time is Movento used at the rate of 10-12 oz/A combined with a spreader adjuvant with penetrating properties. Use sufficient volume to thoroughly wet the tree. Slow drying conditions are best. The material is fully systemic, and should reach the colonies feeding on the roots, as well as those that are visible on the aerial portions of the tree.

Cicadas: While the 17 Year Cicada has garnered much attention from the press, it is also doing a considerable amount of damage where populations are high. Some northern county growers have been on a 5-7 spray schedule trying to fight the egg laying damage. While the high populations that move from woods to orchard are isolated, the damage is real. This is a large insect that takes exposure to fresh insecticide to control it. Where insecticides are being used, many dead cicadas are on the ground, but damage is also present in the form of broken and flagged fruiting wood. See flagged terminals in photo below:

Cicada egg laying flags in a Hunterdon County apple orchard 6/21/21. (Photo – A. Atanassov)

Grapes:

Grape Berry Moth (GBM): The biofix in southern counties for GBM was  5/20. Model timing predicts that treatments 2^nd generation GBM should be applied now in southern counties (Landisville), and by about June 27 in central counties. This timing is for IGR and diamide materials. For other chemistries like pyrethroids and OPs, apply 2-3 days later.

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

Blueberries:           

Aphids:  Aphids are still being found.  Colonies are in the middle range to slightly less compared to last week, the average shoot infestation rate is 7.72% of new shoots infested with a high of 68%.  If aphid populations are present, they still must be controlled, but while working around PHIs and SWD control.

Spotted Wing Drosophila (SWD): Populations are increasing, and as measured by red sticky card counts, they are about double the numbers we saw the previous week. Any field that is colored or starting to color should have protection. Most materials that control SWD also control blueberry maggot (except Delegate and Entrust, which provide suppression). With regards to monitoring for the larval stage, salt tests on mature fruit show no infested fruit as of this week.

Blueberry Maggot (BBM): No blueberry maggot adults have been found yet. Historically we have usually found the first adult maggot fly by June 10-15. The late and possibly smaller population is probably due to the presence of SWD sprays.

Oriental Beetle (OB): Adults continue their emergence as they start to mate and lay eggs. Freshly hatched larvae should be present over the next several weeks. OB treatments should go on by mid-July, or prior to the grubs molting into their 3^rd instar stage.

Anthracnose: Some anthracnose is being seen, and ranges from .05% infected fruit to 1.4% infected fruit.  Therefore, fungicides applications are still merited. Abound, Pristine, Switch and Phosphite materials have a “0” day PHI. Not all materials can be aerially applied. See the 2021 Blueberry Pest Control Recommendations for additional products.

By the Numbers Summary: