Insecticide For Roly Poly Bugs

Whether trundling along or curled up, the little roly-poly’s armored shell may remind you of an armadillo. Scientists must have thought so, too, when they gave this critter its Latin name: Armadillidium vulgare. “Vulgare” means “common” and isn’t a reference to the roly-poly’s lack of manners. Also known as pillbugs, roly polys are a delight for children who like to watch them curl into tight little balls. These small crustaceans live in the soil and primarily feed on rotting organic matter, which aids in decomposition, says UC IPM Online. Roly-polys sometimes feed on roots, leaves and seedlings, as well as fruits and vegetables touching the ground.

Roly-polys are often mistakenly called sowbugs because the two species so closely resemble one another, but sowbugs cannot curl into a ball the way roly-polys do. The roly-poly’s armored plates are generally bluish gray. According to the University of Michigan Animal Diversity Web, they have seven pairs of short legs, jointed antennae and a pair of tails. The tails are usually not visible when you look straight down at the roly-poly; by contrast, sowbug tails are easily seen.

Like lobsters, crayfish and other crustacean relatives, roly-polys breathe through gills. Because the gills have to be kept moist, roly-polys prefer soggy areas of the garden, but can also crawl into damp areas of the home such as bathrooms and laundry rooms.

Because roly-polys have a hard outer shell and live in moist areas, most liquid sprays are unlikely to have much impact on the population. Dry baits containing food mixed with pesticides such as spinosad poison the roly-polys that eat it and provide more effective control. Some brands also control sowbugs, snails, slugs and other insects that live in the soil. Not all brands are allowed around fruit and vegetable crops in some states, so check the label carefully.

Always read the product label carefully to determine whether other insects or animals could be harmed from the bait and always use it as directed.

Bait granules should be scattered on the ground around threatened plants, but not touching them. Granules may be scattered by hand or with handheld, gravity or rotary spreaders. Bait should be spread as evenly as possible at the rate of 1/2 to 1 pound per 1,000 square feet of garden space. If the area to be treated is small, use 1/2 to 1 teaspoon per square yard of soil. Moisten dry soil before spreading the bait, but do not get the soil wet enough to form puddles.

Roly-polys may be seen occasionally during the day, but feed most actively at night, so spreading the bait in the evening is usually best. Baits may be reapplied up to three times every 30 days for heavy infestations. Watering and heavy rainfall can wash the bait into the soil, requiring a fresh application. If the roly-polys are attacking food crops, do not apply poison baits within three days of harvest.

Botanical sprays are available for home use at many garden centers. This ready-to-use, oily spray is completely plant based and contains oil of cloves, sesame oil, soybean oil, thyme and wintergreen. The oils in the spray cling to and interfere with the roly-poly’s neural pathways, killing it. Completely organic, this pesticide may be used on food crops until harvest and can also be sprayed on roly-polys that find their way indoors.

The soil should be moist but not wet. Test the spray on a small area of the plant to be treated and wait 24 hours to be sure it is not sensitive to the ingredients, then spray the plant thoroughly, especially on the undersides of leaves and on the main stem. Spray directly on any roly-polys you see. Spraying is most effective in the evening, when the roly-polys are about to emerge to feed and may be repeated as necessary to achieve control.