Cockroaches

American cockroaches (Periplaneta americana) and Oriental cockroaches (Blatta orientalis) are two common sanitation pests that feed on spilled food and organic waste - including poo (ew). Because of this, they can transmit pathogens like E. coli and Salmonella - among others - which can be bad news for us. As if that wasn’t enough, their fecal matter can aerosolize and cause allergies and asthma when inhaled (double ew).

Sunday Funday Fact: Scientists have found cockroach fossils that date as far back as 300 million years and have even discovered a 3.5 inch long fossil in Ohio! Yikes!

How to ID Cockroaches

American cockroaches are rusty brown with wings that span the entire length of the 1.25-2.25 inch long flat bodies. They have long antennae and a pair of cerci, little sensory projections, that poke out from under the wings toward the rear of the abdomen. The pronotum (the first segment behind the head – think of “shoulders” on a bug bod!) is yellowish around the edges. 

Oriental cockroaches are a little bit smaller – about 1 inch long – dark brown to black, and shiny, with short wings that stop short of covering their rear. They have long antennae and visible cerci on the end of the abdomen.

American and Oriental cockroaches have several lookalikes – including one another! Other cockroaches and prionus beetles can also be doppelgangers for these pests. You can tell a prionus beetle apart by their size – they’re usually larger than American and Oriental cockroaches – as well as their thick, notched antennae and a straight line down the middle of the back where their wings meet. Cockroach antennae are more sleek and slender.

Where Do Cockroaches Live?

Both of these cockroaches can be indoor and outdoor pests across the US. American cockroaches will usually be found in kitchens, bathrooms, and basements if they’re inside, and around the perimeter of the house if outside. Inside the house, Oriental cockroaches prefer basements, bathrooms, drains and sewers. Outside, they can be found throughout the landscape.

When Are Cockroaches Active?

American cockroaches can be active indoors throughout the year. Outside, they are active when the temperatures warm up to 60F. Oriental cockroaches are active above 50F, and are highly nocturnal.

Natural Pest Prevention and Reduction Practices

When it comes to cockroaches, prevention is paramount! 

  1. Remove piles of plant debris, trim shrubs, and remove ground cover from around your house’s perimeter to reduce hiding spots. 
  2. Prevent cockroaches from entering the home by properly sealing windows and using door sweeps or weather stripping. 

If cockroaches do show up, the best way to deal with them is to identify the source! Unfortunately, cockroaches are often a sign of larger structural issues. If you get large or repeat infestations, you should probably have a plumber out to check for pipe or sewer leaks. In the meantime, scouting for existing populations will help you concentrate your control options where they’re needed most. 

  1. First, check the landscape. Look near sewer lines, pipes that exit the home, and around the perimeter of buildings. 
  2. If you do find cockroaches inside, but aren’t sure where the cockroaches are coming from, you can set up sticky traps to track their movements:
    1. Set sticky traps up at floor-level. 
      1. If you have American cockroaches, these are best placed in kitchens, bathrooms, and anywhere else that gets warm and humid. 
      2. For Oriental cockroaches, monitor garages, basements, and crawl spaces. 
    2. Check which areas have the most cockroaches, and which have the least. This will allow you to track movement and identify the source of the infestation.
    3. If you find nymphs or egg cases while you’re poking around looking for their lair, it’s a good bet there is a breeding site nearby – but winged adults can travel far, so keep an eye out!

The Sunday Way to a Cockroach-Free Home + Yard

People often joke that cockroaches will take over when all other life on Earth is gone – for good reason. These insects are tough to get rid of. Keeping things clean is key! Make sure to remove food and water sources and reduce hiding spots like cardboard boxes, bags, or other clutter. Store food in insect-proof containers, and keep garbage in trash cans located away from doorways. Increase ventilation in humid areas, and vacuum regularly using a high efficiency particulate absorber (HEPA) filter to pick up crumbs as well as cockroaches, shed skins, egg cases, and feces. 

Sunday’s plant-powered Bug Doom can be used inside and out to control American cockroaches. Here’s how to use it:

  1. As with all pesticides, always read the label first and wear eye protection and full length clothing when applying.
  2. Spray directly onto American cockroaches, infested areas, and anywhere they might enter the home (around windows, doors, cracks, garages, etc.) – making sure to avoid direct application to plants, water bodies, sewers, drains, or gutters.
  3. Stay off the sprayed area until the product dries.
  4. Reapply as needed.

Sunday ProTip: Sometimes to remove hard-to-deal-with cockroaches, baits are preferred. The cockroaches will collect the bait and take it back to the group, where they will spread the bait via trophallaxis – or exchange of oral secretions (it keeps getting worse, we know) – with other members of the population.

Cited Sources

Alpert, G. and M. Frye. You Say Waterbug, We Say American Cockroach. Cornell University. 

Barbara, K.A. American Cockroach – Periplaneta americana. University of Florida.    

Frye, M. American Cockroach Monitoring. Cornell University.  

National Environmental Health Association. American Cockroach.  

Sutherland, A.M., D-H. Cho, and M.K. Rust. Cockroaches Management Guidelines. University of California. 

The Romero Lab. Common Cockroaches. New Mexico State University.