Many insects get up to no good only at one stage of their lives, but billbugs make a lifetime career of ruining your lawn. The grown-ups chew holes in the grass blades, and their offspring eat the whole plant – roots, blades and all. Small distinct circles of brown or yellowish grass are a good clue that billbugs are at work. You’ll know that for sure if the discolored turf pulls up in a mat, and the roots are covered with a light brown powder that looks like sawdust.
The culprits are easy to recognize. The larvae are white, legless grubs with bright burnt-orange heads. The big guys are brown or black weevils, ¼ to ¾ inch long. You’ll sometimes see them strolling along sidewalks and driveways in early spring. Like all weevils, they have distinctive snout, or “bill”, that gives them their name.
First, here’s the good news: Billbugs usually produce only one generation of offspring per year. The
adults come up out of the soil in the spring to mate and eat your grass. The females lay their eggs in the soil. When they hatch in midsummer, the larvae burrow a little deeper into the ground and go to town on your grass roots. They chomp merrily away through the fall, then sleep through the winter in the soil.
Come early spring, they wake up- still in grub form- and feed even more heavily before pupating and starting the cycle again.
Turf grass is the main item on the billbugs’ menu, but on occasion they’ll wander into the veggie patch for a corn feast. If that happens at your place, launch an attack force of beneficial nematodes.
While adult billbugs can make a mess of your lawn, grubs can destroy it. So close the restaurant early by investing in some beneficial nematodes. They’ll boot the juvenile delinquents out the door, fast! It’s a temporary remedy, though; for long –term control, you’ll need a bigger bag of tricks.
Billbugs tend to zero in on lawns planted in poorly drained soil. If that’s why they targeted your turf,
you’ve got several options for chasing them away. Choosing the best one depends on how big the
problem is and how much time and money you want to spend on the solution. Your taste in outdoor
surroundings will also play a factor. Here are your choices:
– Improve the drainage in trouble spots. This could be as simple as adding organic matter to the soil, or as complicated – and expensive- as calling a landscaping contractor for a full overhaul.
– Replace the grass with perennial plants that take a damp soil.
– Forget growing anything in the problem area, and build a patio or deck instead.
– If you live where you can grow fescue or perennial ryegrass, you’ve got some powerful help. Some varieties of both of these grasses are chock-full of microscopic fungi, called endophytes, that actually kill billbugs and a slew of other lawn pests. There endophytic grasses also have first-class disease resistance, drought tolerance, and all-around staying power.
Once you’ve banished the billbugs, do the following to keep your lawn a big unwelcome mat:
– Blast thatch and do everything you can to keep it at bay. It draws billbugs like peanuts attract squirrels.
– Keep the soil enriched with organic matter, especially compost.
Aerate your lawn so that water can penetrate deeply and spray it once a month with my special
“Aeration Tonic”. What is that you ask and how do you use it?
Use 1 cup of dishwashing liquid and 1 cup of beer. Combine them in a 20 gallon hose-end sprayer,
and fill the balance of the sprayer jar with warm water. Then once a month during the growing
season, spray your lawn with the tonic to the point of run-off.
If it doesn’t work, organize your lawn so that it attracts songbirds. They eat bad bugs by the
Phil Brooks is an expert in pest control home remedies. He currently runs his own company and offers free consultations for Midland Pest Control.