Box Elder Bugs and Stinkbugs hang out and mate on my boysenberries and other...

Asked June 13, 2019, 5:11 PM EDT

Box Elder Bugs and Stinkbugs hang out and mate on my boysenberries and other caneberries every spring. They are out there in force, long before the berries start to ripen. Besides handpicking, is there anything I can do to kill, trap or repel them without compromising the berries? Do these bugs cause damage or reduce yields on my berries? (I can't really tell) I certainly want to reduce their numbers, given the fact that they invade my home in fall and winter. I have tried Rescue brand stinkbug traps and caught nothing.

Washington County Oregon

3 Responses

I am currently working on your question.
  • How many berry plants are in the infested area?
  • You mention the bugs are there every spring. How many years have you had this problem?
  • What have you tried in the past to manage them?

We have about 30 feet of row or more of boysens, and a similar amount of sylvans. We have had these bugs for so many years I don’t remember when they started. We planted the boysenberries about 30 years ago. We have not tried any sprays.

Boxelder bugs don’t cause significant damage to fruit, beyond occasional puckering and will not affect yield. They are more of a nuisance pest.

Stinkbugs can affect both individual fruits and overall yield. They feed on the white center core of the fruit and damage the individual druplets as their piercing mouth parts are inserted. If the bug injects its ‘stink’ while feeding the berry can taste like a stinkbug smells. Correct identification of the stinkbug is needed. Our native stinkbugs have natural predators that help with control. The stinkbugs that come to us from Asia do not have natural predators here yet. In particular the brown marmorated stinkbug causes extensive damage to crops and because of the scarcity (or lack) of natural predators it has become quite invasive. Damage or crop yield changes are directly related to the level of infestation.

Rescue traps use pheromones to attract the brown marmorated stinkbug (their label only specifies that) so if you are not dealing with that particular stinkbug it is unclear if it would be effective. There are other brands that use multiple pheromones that do indicate attracting multiple stinkbug flavors. There is also a specific window (April through September) for trapping stinkbugs in the garden, and the bugs need to be able to crawl into the trap so if it is suspended from something that does not touch the structure of the plant it is not going to catch much.

It’s much more effective to handpick the egg masses or nymphs rather than the adult bug. If you are able to shake the adults and nymphs off the canes and leaves capture them with a cloth or paper under the plant then wrap them up and place immediately in the trash.

As a mechanical means of control consider row covers to keep the bugs out. With the length of your berry rows, and considering the probable height of the plants, that could be a challenge though. If you do try row cover it needs to be in place in the spring before the bugs appear but removed while the berries are in flower to allow pollination.

To deter overwintering stinkbugs and boxelder beetles keep the area clear of plant debris that would provide spots for the bugs to hunker down for the winter, such as brush piles. For the home and exterior structures make sure to seal up any cracks or crevices with a silicone caulk. If there are spaces under the doors install door sweeps. Repair any holes in window screens. Bugs that collect on the home exterior can be handled with a shop vac or a strong stream of water (boxelder bugs can be susceptible to drowning). Bugs that do make their way inside can be captured in a vacuum cleaner bag (preferably a disposable bag-dead and dying stinkbug perfume can definitely linger). Virginia Tech University built simple trap using soapy water and a desk lamp to capture stinkbugs inside. The light fools the bugs into thinking of a nice warm place to mate and the soap in the water prevents the bug from escaping the trap

I’ve listed some of my sources below. I hope this information is helpful.