In the past 24 days we have had only 0.7 inches of rain at the Hudson Valley Research Lab in Highland. Albeit, we are not in a drought situation, irrigation is needed for crops. We are seeing host plants for stink bug are drying out, with Tree of Heaven seed pods and locust bean pods drying down. Reduced food quality from these plants prompt BMSB to start moving to more viable resources such as orchards. This we have been seeing for a few weeks now.
Generally, stink bug move to host plants that have the moisture resources needed to sustain themselves and prepare for overwintering success by feeding abundantly, often in vegetable fields and orchards on irrigated pepper, tomato and tree fruit.
As BMSB continue to move into orchards it becomes more critical to take a closer look at the stink bug features to determine if it is friend or foe. There are three pest stink bug species that will require management and one predatory stink bug worth conserving.
From the seat of the pick-up truck, scouting efforts usually come up short. Upon finding stink bug as you scout, make no assumptions and try to get a closer look. It could save you a late season spray.
One example of mis-identification can easily be made for confusing the spined soldier bug for the brown marmorated stink bug.
The former is a beneficial or predatory stink bug which preys on a wide variety of other arthropods that will feed on the soft bodied insects, such as the larva of lepidopteran pests, soft bodies beetles and such. We have see this species in vegetable and orchards this season and it can easily be mistaken for BMSB.
There is no need to make an application if all you are seeing is the spined soldier bug.
Overview: As BMSB continue to move into orchards it becomes more critical to take a closer look at the stink bug features to determine if it is friend or foe. I was recently sent an image of a brown colored stink bug and it was assumed to be a Brown Marmorated Stink Bug (BMSB) Halyomorpha halys (Stål) crawling up the trunk of a tree. As I increased the size of the image it became apparent that the shoulders has spines at the tip, its legs were a single cream color, and there were no cream colored dots along the edge of the leading edge of thorax and abdomen. It was in fact a spined soldier bug, Podisus maculiventris (Say).
Newly emerging nymphs have been on the increase, nearing or exceeding threshold in Webster in Wayne County, Highland and New Paltz in Ulster County, Fishkill in Dutchess and Campbell Hall in Orange County traps last week. The 2nd instar of Brown Marmorated Stink Bug (BMSB) Halyomorpha halys (Stål), newly hatched from eggs last week, are making their way to traps and increasing in numbers throughout the state. All life stages along 8 commercial blocks in mid-Hudson Valley orchard sites have been observed this past week. Movement to apple foliage and fruit is beginning.
Trap numbers of stink bug in combination with scouting, should precede management during this time of BMSB population build-up. Review labels for pre-harvest intervals (PHI) when choosing materials as the most effective materials have 14 DTH constraints.
When thresholds are exceeded or stink bug become visible along the orchard edge, border row applications should begin. These should then be followed by alternate row, then whole orchard applications as movement of native and BMSB populations begin to migrate into orchards. As stink bug are orchard edge opportunists, the majority of the injury to fruit will occur along the 30′ perimeter edge.
Insecticides selected for whole orchard applications should also have strong efficacy for apple maggot, obliquebanded leafroller, and as we move into September, codling moth for which management may be required.
The brown marmorated and native green stink bug are arboreal insects, residing in woodland habitat. However, when populations continue to rise through July into August, increasing numbers of adults and nymphs can be observed on tree fruit.
This has occurred over the past three weeks. Increasing presence of the insects in trees will result in injury in late peach, pear and apple rows bordering woodlands and hedgerows. Nymphs ranging from 2nd to 5th instar of both species have been observed feeding on fruit along the orchard perimeter this week.
This newly developing partial second generation will significantly increase BMSB population in woodlands. As host quality from the arborial woodland habitat declines, increasing migration to tree fruit is very likely through the end of August on through to the end of October. Increased scouting should be based on recent and upcoming Tedders trap captures. This will be especially important if weather turns dry with irrigated tree fruit becoming a favored host of BMSB as adults begin to feed more intensively as they prepare for their overwintering phase.
Monitoring: Remember that trap captures combined with scouting for the various life stages of the insect along the orchard perimeter rows should be the basis for insecticide applications. Unlike most other pests, we should not be using IPM thresholds based on stink bug feeding that results in fruit damage. As expression of the injury occurs 7-10 days or longer after feeding, you would have missed your opportunity to reduced injury if you postpone preventative applications while waiting on injury that has already occurred to become visible.
Use a conservative presence and trap threshold on through harvest. Finding a single BMSB or green stink bug in the tree canopy within 100′ of scouted perimeter row would be considered a conservative threshold. Driving along the orchard will likely spook the insects. You’ll need to stealth your way quietly around the orchard…its good exercise in the early evening or morning. Green stink bug tend to remain low while BMSB tend to move to the tops of the trees to feed.
Management: When selecting insecticides for border row, alternate row and whole orchard applications you should consider constraints on your markets. If weather turns to drought, then longer residue based on the active ingredient minimum residue level (MRL) could become an issue, especially in EU markets and Israel. Review your options carefully with regards to harvest dates, PHI’s, re-application intervals and seasonal A.I. volume.
When BMSB populations dramatically increase during late season, migration into orchards can be dramatic. BMSB have been known to funnel down to the last variety standing (such as the high value Pink Lady). In which case applications in late October may be warranted!!
Applications of insecticides selected for whole orchard applications should also have strong efficacy for apple maggot, obliquebanded leafroller and 3rd generation codling moth if CM infestations from 1st or 2nd generation are active, which may also require management.
One of the most effective tools for use to manage BMSB is the active ingredient bifenthrin in a number of formulations.
Bifenthrin has a 12 hr. re-entry interval, 14 day pre-harvest interval and a 30 day re-application interval.
We received notice that the EPA has approved the Section 18 application for bifenthrin for use against the brown marmorated stink bug for 2019. Links below provide access to PDF copies of the Section 18 labels for materials containing the A.I. bifenthrin.
Labels should be made available to the applicator during bifenthrin applications. These can be printed or available as digital files such as PDF’s on tablets or smart phones. The exemption is valid through October 15th 2019 as a “Section 18 EXEMPTION under FIFRA, FOR DISTRIBUTION AND USE ONLY IN Columbia, Dutchess, Orange, Ulster, Monroe, Orleans, Wayne and Niagara Counties this year. Use in any other counties is prohibited in NEW YORK STATE”.
For all Bifenthrin products, the Section 18 permit can be used in apple, peach and nectarine. Do not apply more than a total of 0.50 lbs ai/acre per season. Apply as necessary to maintain control using a minimum of 30‐day spray intervals, 14-day pre-harvest interval and a 12 hour REI. Bifenthrin labels include: