Since the current heat wave began last weekend, we have been seeing a large increase in stink bug sightings in central Ohio. Stink bugs have not been commonly found for most of the summer even in known hot spots like Columbus. We are now finding stink bugs in late plantings of sweet corn (Figure 1), where their feeding results in shriveled kernels (Figure 2). We are also seeing them in bell peppers and apples (Figure 3) and soybeans , as well as around buildings. Most are the brown marmorated stink bug, but we are also finding some of our native green stink bug and brown stink bug. In soybeans last week, the majority of stink bugs that we found were large nymphs (Figure 4), with only a few adults, but in the past few days we are starting to see fewer nymphs and more adults. It is the new adults that are quite mobile that will be seeking protected places to overwinter. They are particularly active when temperatures are above 80 degrees, as they have been for the past week. Our trapping network has shown that stink bug activity is highly variable around Ohio; there are a few hot spots such as Columbus, but some locations have had no detection of stink bugs, and many locations with only light detection. Reports on catch of brown marmorated stink bug in our trap network can be found with this link: https://docs.google.com/spreadsheets/d/1LtyYFH06PRhb2OOij97pMULqDuL9zOnDRuNinI3dxzk/edit?usp=sharing . Growers with susceptible late-season crops should scout their fields to determine whether stink bugs are present.

Figure 1. Brown marmorated stink bug, nymphs and adults, on sweet corn ear.

Figure 2. Shriveled kernels of sweet corn caused by stink bug feeding through the husks.

Figure 3. Adult of brown marmorated stink bug on apple.

Figure 4. Nymph (immature stage) of brown marmorated stink bug on soybean.

Various OSU cooperators, mostly specialists and Extension educators, have been monitoring for spotted wing Drosophila (SWD) adults in a statewide network since around mid May. So far positive detections have been made in Franklin, Greene, Clinton, Clark, and Wayne counties, with an unconfirmed report from Champaign county. Several other counties in the SWD trapping network have not reported yet so this is what we know to date.

While the captures are still relatively low, they are higher than this time frame last year.

If you grow raspberries, blackberries, grapes, peaches, strawberries, or blueberries that have ripe or ripening fruit, you should be alert to any SWD reports in your area and be prepared to start a treatment program if found on your farm. Here is a quick SWD factsheet and insecticide list for your reference (https://u.osu.edu/pestmanagement/files/2017/04/SWD_Ohio_handoutV15-1fd4zp6.pdf).

Frame grab of latest SWD video explaining trap set up.

If you don’t have ripe or ripening fruit yet, it is still not too late to put a trap up and look for adult flies. A new 3 minute video showing how to set up the SWD trap we currently recommend, the Scentry trap, has just been created and posted on the OSU IPM YouTube channel at https://youtu.be/z9IeuYECnJk (Fig. 1). Remember that any SWD trap will catch non-target insects, so be sure to have your catches inspected for the right species. The Scentry trap and lure can be purchased at Great Lakes IPM (http://www.greatlakesipm.com).

–Jim Jasinski (jasinski.4@osu.edu), IPM Program; Celeste Welty (welty.1@osu.edu), Dept. of Entomology

Spotted wing Drosophila (SWD) is a serious pest of raspberries, blackberries, blueberries, strawberries, grapes, and peaches. For the past five years, we have established a statewide monitoring network in 15-20 Ohio counties to look for this pest on grower’s farms in an effort to help them manage it better. With few exceptions, in every county where we have placed traps, we have found SWD. This network is typically established in the first week of June and runs through September, and consists of weekly trap checks and reporting.

Over the years we have gained some knowledge about the overwintering habits of this pest, which appear to be near wooded areas. This year we set out baited Scentry traps early at a few small fruit fields around the state to see if SWD are present in those locations. In Franklin Country, one trap was in place in a small raspberry patch for the entire winter, and four additional traps were placed near the boundary between a wooded fencerow and the raspberries on May 11th. Likewise, traps were placed in the boundary between the woods and berry fields in Greene and Clinton Counties on May 10^th. In Wayne County, traps were also placed near a strawberry field in mid-May. We have detected SWD adults at all four of these locations within the past week. In Franklin County, the traps in the berry patch had no SWD, but one trap in the distant treeline did have one male SWD on May 25^th. Traps at Greene, Clinton, and Wayne locations found SWD adults on May 23^rd. These catches are 3-4 weeks earlier than we have detected them in past seasons. The earlier finds are interesting but not surprising, because we were looking for these pests earlier in the season at a location where they are likely to overwinter, in combination with a mild winter in which high survival was likely.

SWD adult imaged through stereo scope. This is a male, note spots on wings.

SWD Scentry trap with Scentry lure (inside) and 25% apple cider vinegar drowning solution set in a raspberry field.

What does finding SWD this early in the season mean for growers? We are still learning about this pest and how to interpret the nuances of early season detection and its effect on early season management. Strictly speaking, the threshold for this pest is one adult fly detected in the fruit planting, so if there is any ripe or ripening fruit on a farm, we recommend starting an insecticide treatment on a seven-day schedule through harvest. If growers cannot treat due to picking or harvesting considerations, we strongly recommend they conduct salt water tests on berries collected from several locations around their susceptible fields to verify no SWD larvae are found in the berries. If larvae are found, treatment should begin immediately through harvest.

All growers of these susceptible crops are encouraged to use a trap to detect the adult flies, and test ripening fruit for presence of larvae using a simple salt water test.

A factsheet on how to conduct a saltwater test can be found here: http://u.osu.edu/pestmanagement/files/2017/04/SWD-salttesthandout-updated-pnd335.pdf.

Insecticide options available to growers along with pre -harvest intervals, are shown on page 2 of a factsheet: https://u.osu.edu/pestmanagement/files/2017/04/SWD_Ohio_handoutV15-1fd4zp6.pdf

It’s that time of year when many pests become active and begin moving from their overwintering sites to crop fields. One of the pests we have been monitoring statewide over the past six years is the Brown Marmorated Stink Bug (BMSB). This is a rather large brown mottled stink bug known to attack field crops, landscape and ornamental plants, and a wide array of fruit and vegetable crops including apples, peaches, caneberries, blueberries, grapes, beans, sweet corn, peppers, tomatoes, and many more crops.

Brown marmorated stink bug, adult female; note the distinctive white bands on the antennae.

Brown marmorated stink bug, nymphs, feeding through husks of sweet corn.

In our pheromone trapping program in Ohio since 2011, we have typically geared up for trapping this pest in early June and finished in September, but as part of a large multi-state research project this year, we established monitoring sites by early April in several central and southwest counties using two different style traps; the traditional black pyramid and a new clear panel sticky trap. Both traps use a dual pheromone lure that is quite attractive to both male and female adults as well as to nymphs of BMSB. The study is designed to compare one type of trap to the other in terms of catch efficiency, and to determine when the BMSB become active and leave their overwintering locations in nearby woods to move into adjacent fields. So far we’ve been catching male and female BMSB in Franklin, Greene, and Clinton counties since mid April.

New clear sticky panel trap for BMSB.

Traditional pyramid style BMSB trap.

Even though we haven’t seen much injury from BMSB in fruit and vegetable crops in most Ohio locations over the past few years, it is possible that the overwintering survival rate of the stink bugs is higher this year due to the mild winter.  It would be prudent for growers to keep a close eye out for this particular pest in 2017. For more information about the biology and management of this pest, visit http://www.stopbmsb.org.

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