Getting Rid of German Cockroaches

This week I’m practicing what I preach and I’d like to tell you about it.

I recently moved to a six unit apartment building. It’s a fixer-upper. Another woman moved in the same weekend I did and we’ve become friends. Within the first week, I came home to some bugs drowned in a cup of water left outside my door...It didn’t take long to establish my reputation as the bug lady. 

My neighbor had done some inspection as she moved in and found these pests. The next step in IPM is identification. In her case, leave me a cup of bugs. Her pests were a Western Conifer Seed Bug and a German Cockroach.

The same day she left me the bugs, she went to the store and bought a fogger. Luckily, I got back to her before she set that off!

For the Western Conifer Seed Bug, I explained that it wasn’t going to infest and applying pesticide wasn’t going to remove them or prevent more from getting in. I sent her to last year’s post on these (and other stink bugs). http://stoppests.typepad.com/ipminmultifamilyhousing/2010/10/stink-bugs-and-other-fall-occasional-invaders.html

But the roaches are a problem. They trigger asthma in people who are sensitive and can cause asthma in pre-school aged children. And they infest. Especially the German Cockroaches. There is a kid in the building, a man with respiratory problems, and my apartment (which is currently roach free…I’ve got sticky trap monitors down to check).

I wrote a letter and made five copies. One for each of the units in my building. IPM is a team effort. Cockroaches reproduce too fast to waste time pointing fingers. I tweaked my letter so I could share the technical parts with you all (see below).

This story is still unfolding. We’re handling it as a team. As it turns out, one gentleman had a pipe leaking in his apartment. He shut off his water and has been living without it for weeks. He wasn’t reporting the leak because he was embarrassed about the cockroach infestation in his home. Meanwhile, his wet carpet became covered in mold. He is the resident with respiratory problems…

Using IPM, we determined some of my neighbor’s cockroaches were coming from his apartment and he is now getting the help he needs. Both from a plumber and a PMP. Plus, knowing his neighbors are there to help not to judge probably gives him some peace of mind.

So without further ado...

How to Kill German Cockroaches In an Apartment

Identify your insects so you can target your control efforts. If you someone to identify bugs for you, put them in a cup or baggie drowned in rubbing alcohol. We caught a German Cockroach (~1/2”, light brown, with “racing stripes” on the front). The rest of this is about German cockroach control, since that’s what we found.

Phase I: Figure out where to focus your efforts. 

Find where the infestations are. Cockroaches can travel along pipe chases and between rooms, but they prefer to stay-put. Monitoring may determine that your roaches keep getting introduced from a source outside of your home. In that case, we will want to focus control efforts on the source while also eliminating them from your home.

• Buy sticky trap monitors at any home store and place them along walls, under cabinets, etc. around the kitchen, bathroom, living room, and bedroom. I do: under the kitchen sink, by the stove, by the fridge, behind the couch, behind the bed, behind the toilet.

 

• Leave them for at least two nights and see what they catch.
• Where they catch cockroaches, focus your efforts. If there are baby cockroaches on the traps (little ones without wings), then focus really hard in that area. “Efforts” will include sanitation, exclusion, and pesticide application.

Phase II: Knock-down

Take away pest food and water without disrupting the cockroaches too much. 

• Reduce food sources: Clean the kitchen, don’t store recyclables inside your apartment, and take out the trash regularly. Roaches are most active at night, so that’s when you want to make sure food is put away. Keep pet food in containers and cover it at night.
• Reduce water sources: Fix any leaks, wash and dry dishes nightly, pick up pet water at night, and cover the sink drain with a plug or dry towel at night.
• Store food in sealed containers or in the fridge.

If you have a large population, you can kill a lot of roaches using a vacuum cleaner. A HEPA filter is best so the roach allergens don’t get airborne. Use the hot air from a hair dryer to flush them out of cracks and crevices. This works best with two people: one to operate the vacuum, another to pull out appliances/use the hair dryer. If you suck up roaches, immediately take vacuum bag out/empty the canister. Sucking up the roaches won’t kill them. Tie the bag/canister contents in a plastic bag or two and throw them away outside. If you only have a few roaches, you can create a bag in the vacuum hose using one leg of a panty hose. See: http://stoppests.typepad.com/ipminmultifamilyhousing/2011/07/vacuums-very-accessible-control-sample-newsletter-article.html

Pesticide application. DO NOT USE FOGGERS/BOMBS. They just don’t work. Usually it just drives them deeper into the cracks/into your neighbor’s apartment for a time. The ones that look dead are sometimes faking.

• The most effective option is bait. Bait works as a stomach poison. The roaches take a little time to die, but they may crawl back into the hiding spots. When they die, the other roaches eat them and they get poisoned too. You get more bang for your buck with bait. If you live in multifamily housing, have you pest management professional (PMP) apply all pesticides. The PMP will use either the pucks (tamper resistant packaging) or the gel in a syringe. Either way, he should follow the label directions and place the bait where the sticky traps caught roaches. 
  
  Sprays, cigarette smoke, and strong cleaners can contaminate the bait. You want the bait to be the only roach food in the area and smell good to them. Bait lasts a few months, or until the roaches eat it all. If they aren’t eating it, ask the PMP to try a different brand of bait. Some roaches are picky eaters.

• The PMP may puff insecticidal dust such as boric acid or diatomaceous earth (“DE”) (insecticide-grade, not pool-grade) behind cabinets, into gaps around pipes, behind baseboards, etc. If you can see the powder, there’s probably too much. You want a THIN layer down. The roaches pick it up and ingest it when they groom themselves. Mixing it with food will NOT make it work better. Boric acid and DE last as long as the dust stays dry.

Phase III: Thorough Cleaning

Give the roaches a week or two to go about their usual routines (through the dust) and to eat the bait. At first you may see more activity, but those are just the roaches acting odd because they are poisoned. You should see populations go down and the monitors will catch fewer bugs within two weeks. You can vacuum up bugs you see or flush them down the toilet.

Do a thorough cleaning of the areas in your apartment where there was roach activity. Focus on removing the little black spots (roach poop, a.k.a. “frass”). Roaches communicate through the frass and it also triggers asthma. Simple cleaning products will clean it up.

• In the kitchen: empty and wipe down cupboards/shelves, under the stove top, under the stove, under the fridge, etc.
• In the bathroom: keep the moisture down.
• Mop/vacuum floors.

Exclusion: Reduce roach hiding spots by filling cracks and crevices with caulking. If you live in multifamily housing, call in a work order for maintenance to do this. You can also use copper scrubbing pads from the dollar store to stuff large gaps around pipes (steel wool will rust). Roaches also hide in paper bags, cardboard boxes, and piles of paper so recycle or throw these away.

Phase IV: Maintain control/ monitor for new activity

Check the control: place more monitors and keep an eye out for new evidence (roaches, roach eggs, or their frass). IPM is a continuous process.

For pesticide questions, consult the National Pesticide Information Center
www.npic.orst.edu or 800-858-7378

Comments

[Tyrone Swopes]

Roaches are a huge problem in most houses and apartments. We also had that dilemma last year when our children got sick due to asthma. So we made it a point to regularly keep an eye out for those pests, and we still do after a year of being roach-free.