The reviled roach has a role in the garden

Friday, July 24, 2015

As published in the Miami Herald, 7/24/15.

American cockroach


When I lived in New York, I was plagued by what we called waterbugs. They are what Floridians call palmetto bugs. Nearly universally despised, roaches play a necessary garden role as recyclers. Why do we hate them so?

How can I begin to wax sentimental about roaches, those loathed inhabitants of the dirty, filthy, disease-ridden corners of our world? What purpose could they have besides tormenting us?

I began to think about this: Mosquitoes are far, far more harmful to us than roaches. Malaria, transmitted by Anopheles mosquitoes, killed over half a million people in 2013, most of them children, according to the World Health Organization. If I were a roach, I’d be yelling “SEE? SEE!? Mosquitoes did that, not us!”

In most cities, you’ll encounter palmetto bugs, aka the American roach (Periplaneta Americana) or the smaller German roach (Blattella germanica). The animals we call roaches fall within the order Blattodea (along with termites). Those that hang around houses are called peridomestic.

Here in South Florida, we may encounter many different species of roach in the garden and the home. There’s the smallish cricket-like oriental cockroach (Blatta orientalis), and I am told the huge Madagascar hissing roach (Gromphadorhina portentosa) has been spotted, but I’ve never seen one outside a zoo display. The latter is a common insect pet, and I dare say, cute. Unlike many other roaches, hissers cannot fly.

When they do fly, they do so haphazardly, like a new driver veering out of control. They don’t simply flee but make you think they may inadvertently fly into your face. However, the Cuban cockroach (Panchlora nivea) when disturbed seems to flutter away unobtrusively like a moth. Like most roaches, it is nocturnal and not an indoor pest. Unlike most roaches, it resembles a pale green pumpkin seed.  
A Cuban roach, unlikely to stray indoors

Back to katsaridaphobia, or cockroach phobia. Roaches just look dirty, scurrying and obstinate. Don’t they know waking me up by crawling across my lips is really rude (unfortunately true story)?

Truth is, I’ve found very little evidence that they spread much disease. It’s certainly possible, but doesn’t seem to be the rule. Worsening asthma and allergy symptoms have been linked to roach exposure, especially in children. But I’m more inclined to blame industrial pollution. Roaches do like to excrete a lot though, rude little buggers, and that may cause a reaction.

Most are omnivores, though some roaches are specialists. The ones that pester us, like palmetto bugs and German roaches, are the former. They like rotting wood and decaying organic material — detritus of the forest floor. This is where they help us in breaking down and recycling dead plants into, eventually, rich soil. My compost bin is chock full of roaches of at least a couple species, including very big and well-fed palmetto bugs. They speed the breakdown of my yard waste into compost, though admittedly, opening the compost lid at night, flashlight in hand, is not for the squeamish.

One less America roach to contend with

Replacing rotten wood in your home’s structure will reduce its attractiveness to roaches. Sealing areas where pipes enter and exit the bathroom and kitchen helps. Dripping pipes are a water source and help to cause nearby wood to decay, so fix them.

I keep leaf litter in my yard, but not abutting the house. A good exterminator can use a minimal amount of poison strategically to help. Avoid storing corrugated cardboard, especially in a warm, humid garage. Roaches adore cardboard, particularly in the form of a box filled with paper and glue to eat. I know the horrors that can foster.

The Florida woods cockroach, Eurycotis floridana, is a native originally called the palmetto bug. A bit shorter and rounder than the others, it usually stays outdoors under leaf litter and other debris. When threatened, it can emit a foul-smelling discharge. The smoky brown roach (Periplaneta fuliginosa) is another you are likely to encounter around the yard. It is uniformly dark brown, without the lighter thorax of the closely related American roach.

Roaches are everywhere — I’ve even encountered palmetto bugs in Death Valley National Park, though only in the hotel bathroom where they could access water brought in through plumbing. We can reduce them in our homes, but they will always be near. Try and remember, they look gross, but aren’t all that bad.