During a recent visit to a local business, a tiny little beetle was discovered making its way along the baseboard, laboriously climbing over each bump in the carpet. Alarmed, the owner rushed over and glowered at the intruder, commenting that it was the second one she’d seen in as many days. She promised to pick up an insecticidal “bomb” to set off that evening after closing. I rescued the pint-sized ground beetle and carried it outdoors before it got stepped on. I’m sure it was relieved to be deposited in the grass, where it could go back to preying on smaller insects.
With winter approaching, many insects are looking for a place to shelter until spring. They don’t know the difference between a bark crevice and a door frame, and they unwittingly end up in our houses. Most are completely harmless, and can be simply redirected back outside. Instead, we reach for the can of bug spray.
We seem to have a national paranoia about insects. When I volunteered at the master gardener helpdesk, I used to get calls asking about what insecticide to spray—and it turned out that the homeowner had seen ONE little bug! They didn’t even know if it was harmful, helpful, or just passing through. If it has more than four legs, it dies.
While I tend toward organic gardening and minimal chemical use, I’m not a purist. I’ve used flea bombs on infested carpet and sprayed a house for termites. To keep the pine beetles from spreading, we used insecticides on the beetle-killed Ponderosa we cut down several years ago. And when I gardened in northern California, I used copious amounts of Deadline, a liquid snail and slug killer.
However, I also have learned to live with a bit of damage to my garden—a few holes in some leaves or a defoliated sprout. Instead of heading outside with a spray can in hand, I prefer to learn more about the little creature so busily going about its daily life. On closer inspection, a lot of insects (and even a few spiders) are quite beautiful, and they’re all interesting.
It’s an entire ecosystem right in my backyard. The herbivores graze and provide food for the predators, which in turn are eaten by even bigger (or more ferocious) hunters. Some lurk, others pounce or are faster or better armed. The prey, in turn, are good at hiding, defending themselves, or just plain breeding—kind of like rabbits. And the diversity is stunning.
We all need to stop, take a deep breath, and ask ourselves, is the presence of one or two insects more hazardous to our health, compared to dousing our homes and yards with poisons? Do we really need to kill every creature that dares to cross our property line? Here are a few points to consider.
What kind of bug is this? Without a confident ID, it’s impossible to know if you’re dealing with a pest or an innocent bystander. Even catching an insect at the scene of the crime isn’t proof—it may be eating the bugs doing the actual damage.
Is this insect or spider dangerous? Very few species actually poise a threat to human lives. Colorado has black widows, and they can definitely make us sick if they bite us. However, the rest cannot hurt us. In spite of supposed eye-witness accounts and frequent misidentifications, we do NOT have Brown Recluse spiders. We’re too high and dry for them.
Is this insect killing my plant? The presence of a few bugs isn’t going to cause significant damage. Moreover, those bugs may be the “good guys,” on patrol for aphids or caterpillars (such as this assassin bug, left). Spraying upsets the balance of nature, and often leads to more problems, not fewer bugs.
Even if the plant is being defoliated, is that really a problem? It depends on the time of year. Having to put out new leaves in spring or early summer can drain a plant’s resources. Losing them now, when they’re about to fall off anyway, isn’t a big deal.
How valuable is the plant? Are you spraying an established tree worth thousands of dollars in property value, or a pot of geraniums?
Are bees visiting this plant? Most insecticides kill bees as readily as other bugs. With bee populations at risk, it’s up to us to do what we can to protect them from ourselves.
Finally, if you decide you do need to take action, be sure to read the directions and safety instructions on the pesticide’s lable. Many chemicals are quite dangerous, especially if they are inhaled or come in contact with your skin. Protective clothing is essential. Pick a time when the winds are calm (tricky in Colorado!) so you don’t inadvertently spray the wrong plants. And follow the directions when washing and disposing of empty containers.
Ground beetle photo, at top, from the Illinois Department of Public Health.