Pill bugs, doodle bugs, roly-polies. These little critters have some cute names, and it’s so fun to watch them roll up into a little ball when you touch them. They are a harmless bug with no bite or sting, and I always enjoy watching them crawl around. Pill bugs have become a hot topic of discussion in our demonstration garden after they munched their way through a few rows of tender vegetable plants.
The common pill bug, Armadillium vulgare, is an isopod. This is a type of Crustacean that has adapted to life on land. They actually breathe through gills and like wet environments. Pill bugs are usually about one centimeter long and gray or brownish in color. Their thorax is made up of seven overlapping plates and they have seven pairs of legs. Pill bugs can roll up into a tight little ball when they are disturbed, which is how they get their fun roly-poly name.
Pill bugs usually live in damp areas under mulch or leaves. They typically come out at night to feed on mulch, debris, or other decaying material, but they also like to feast on tender young plants and roots. In a vegetable garden, they can devour small plants overnight, and they love to eat strawberries or other fruit that has contact with the ground. Pill bugs recently ate a row of cucumber transplants in our vegetable demonstration garden, and I lost a 12-pack of freshly planted petunias overnight to a mob of pill bugs.
Pill bugs are especially bad in wet years, which is why we saw so many last summer. They also thrive in areas with a lot of mulch or debris. If you have serious problems with pill bugs, consider spreading out the mulch or adjusting your irrigation system so the area can dry out a little. Eliminate hiding and breeding sites like flower pots, dog houses, wood, or bricks that are laying directly on the ground. Permethrin or pyrethroid insecticide products can be used to control pill bugs outside.
In the demonstration garden, the Master Gardeners have found that beer works as an effective trap for pill bugs. Use a shallow container like a cat food tin, bury it so the top of the can is level with the soil, and fill it with beer. Pill bugs, and even snails, will crawl into the can and drown. I have been surprised at how many pill bugs are trapped with this method.
For more information about lawn and garden topics, contact Kate Whitney, Horticulture Extension Agent, at 512-943-3300.
