Debbie Arrington

Seeds: Brown marmorated stink bugs seeking cozy winter homes

Brown marmorated stink bugs hang out on a house on 13th Street in midtown Sacramento. The stink bugs, native to Korea and Taiwan have established a large population in downtown Sacramento.
Brown marmorated stink bugs hang out on a house on 13th Street in midtown Sacramento. The stink bugs, native to Korea and Taiwan have established a large population in downtown Sacramento. Sacramento Bee file

Near Sacramento’s Fremont Park, this horror story has become a gruesome October tradition: The attack of the stink bugs.

Brown marmorated stink bugs – the dreaded BMSBs – have tired of ravaging fruit and foliage. After a summer spent sucking the life out of juicy tomatoes and feasting on sunflowers, these invaders want to take a long winter’s nap. And from their view, a nice warm and dry spot in your closet or car trunk would suit them just fine.

“Ever watch ‘Caddyshack’? I feel like Bill Murray fighting with the gopher,” lamented Brian Sanders, who lives on Q Street across from Fremont Community Garden. “They’re bad. No matter what I do, they keep coming back.”

Since September, Sanders has found stink bugs in his bedroom drawers and his clothes. “The only thing I can do – catch and flush,” he said. “I’m actually at the point where I’m considering toxic bombs and moving out of my place for a couple of days. ... They’re violating my space.”

This has been an active year for Sacramento’s stink bugs, an invasive pest that’s making many miserable – me included. Months have been spent trying to outwit this prehistoric remnant of insect evolution. They’re big! And scary! But like zombies, stink bugs are relentless.

BMSB do smell awful; that’s their defense. They also stain when squished. Wear gloves. And don’t smash them on a white rug or khaki pants.

It didn’t use to be this way. BMSBs first popped up in Sacramento in 2013. That’s after a cross-country progression that started in 2001 in Pennsylvania. Native to China and Japan, this voracious pest smuggled its way into North America via cargo container. Now it’s been reported in at least 40 states.

In the Northeast near the hot zones for BMSBs, stink bugs can destroy 50 percent of a crop in infected orchards. BMSBs do about the same damage to tomatoes. To Sacramento Valley farmers, BMSBs are a real financial threat.

Besides food plants, BMSBs go after all sorts of ornamentals from butterfly bushes to pistache trees. These bugs are easy to spot: At maturity, BMSB females measure almost 3/4 of an inch in length, much longer than native stink bugs.

In the Fremont Community Garden (where I have a plot), BMSBs attacked a wide range of crops and flowers, but some more than others.

“They love sunflowers most,” said Linda Dekker, who participated in an experiment with the California Department of Food and Agriculture and University of California master gardeners. “Then, they go after the kale, chard and horseradish. They like corn, too. If they had their preference, they want tomatoes and fruit plants. But they’ll eat anything in a pinch.”

As a “stink bug crop trap,” Lemon Girl sunflowers surrounded Dekker’s garden plot. Rows of dwarf sorghum, a relative of corn, and dwarf sunflowers also were planted to test their BMSB appeal. A few 10-foot volunteer sunflowers sprung up in the middle of the test area, too.

In all, three 10-by-20-foot Fremont Garden plots became bug labs. Volunteers examined the plants, then vacuumed up the stink bugs for counting. About 540 stink bugs were removed. The census saw a huge spike in BMSBs in mid-June and another in mid-July.

The tallest sunflowers – those volunteer giants – attracted the most bugs, which were easy to vacuum as nymphs. Pearl-like eggs on the underside of leaves also could be seen on the tall sunflowers; those whole leaves could be picked off and destroyed.

No stink bugs were found on dwarf sunflowers. Dwarf sorghum also didn’t draw their interest.

A giant sunflower in my own garden plot became a stink bug magnet. They ignored most of the nearby tomatoes (except the Super Marzano) and became easy pickings off the sunflower’s leaves, where they tended to roost. I knocked them into a bucket of water with a little dish soap or just grabbed them with my garden gloves.

One taught me to be cautious and consider face protection. Full of sunflower pollen, the stink bug flew off the plant right into my forehead to go splat, kamikaze style. I started sweating profusely and my eyes stung. My forehead was covered with something that looked like thin yellow mustard, the ultimate stink-bug diss.

Fremont’s fruit trees took the heaviest toll this summer. Only pears and apples protected with fine mesh bags escaped the BMSBs’ appetite.

Damaged fruit looks like it’s been stung by angry wasps. Ugly welts swell where stink bugs plunged their mouth parts and poisoned the flesh. Eventually, the fruit becomes an empty sack, sucked dry.

Indoors, stink bugs are mostly annoying.

Dekker, who lives in the Fremont Mews overlooking the community garden, has found Terro ant spray an effective deterrent to the intruding stink bugs, which can squeeze under doors or through tiny cracks. She’s also tried taping completely around windows and screens to close stink bug-friendly gaps. A few bugs still find their way indoors.

“The good thing: They’re slow and they don’t bite,” Dekker said. “They’re not hard to catch.”

Instead of one or two generations of stink bugs, the Fremont neighborhood saw three generations in a single season. Each mama stink bug can produce 300 eggs per season. Another round means a lot more stink bugs looking for winter accommodations to hibernate.

“People will be seeing them in their homes and businesses potentially in large numbers,” said Chuck Ingels, farm adviser for UC Cooperative Extension, who coordinated the stink bug study. “It’s the beginning of problems for many homes and businesses and a nightmare for some.”

Sanders saw the buggy baby boom firsthand.

“When the babies hatched, it looked like heat rising off the road,” Sanders said. “They were about the size of BBs and hopping up and down.”

Poor fliers except in short bursts, mature stink bugs get around by hitchhiking on cars, trains, ships and people.

Ingels tracks BMSB sightings throughout the Sacramento area, from midtown to Fair Oaks. A downtown worker found dozens of stinkbugs on his parked car at O and 11th streets, according to a recent survey submitted to UC’s bug tracking website. Hundreds more BMSBs were found in trees lining downtown streets. Besides clinging to cars, these bugs can jump into backpacks, grocery bags or purses.

If you don’t want these pests hitchhiking home with you, always take a quick look around your car – especially in parts of downtown along O, P and Q streets where large infestations have been reported. Shake out bags before bringing them inside your home.

And if you see any BMSBs, squish ’em.

Debbie Arrington: 916-321-1075, @debarrington

Stink bug help

How to tell if it’s really a brown marmorated stink bug:

Report BMSB finds and see Sacramento’s stink bug map:

Details of the Fremont stink bug sunflower study: