Pillbugs

Pillbugs are also called woodlice or sowbugs and while many people have had interactions with them in their backyards, these insects are not typically welcome in the home.

Biology of Pillbugs
Interestingly enough, pillbugs are more similar to crayfish and shrimp than insects. In fact, these are the sole crustaceans that live solely on land. Pillbugs typically live outdoors in moist environments, but they can also end up inside buildings. Pillbugs are usually between ¼ and ½ inch in length. Their coloring is typically slate to dark gray. They have segmented bodies that are oval-shaped and concave or flat below but convex above. Pillbugs have seven sets of legs along with two sets of antennae, one of which is easily visible. Pillbugs do not have any appendages along the rear of their bodies. They can also roll into tight balls when they are disturbed, an action which has given them the nickname of roly-polies.



The pillbug is a scavenger, mostly feeding on various organic decaying matter. It is also possible, but rare, for pillbugs to feed on plants that are young. In that case, they will not typically cause much damage. Pillbugs will spend most of the daytime hidden underneath objects. When by buildings, you can find them underneath flower pots, stones, boards, compost, mulch, or anything else that sits on damp ground. You can also frequently spot them behind the edge of the grass where it meets the foundation or sidewalk. Female pillbugs lay eggs and then carry them in a pouch under their body. The young hatch from the eggs but stay in the pouch for as long as two months following the hatching. They will reach maturity in approximately a year. Pillbugs typically breed during the spring. Pillbugs can live as long as three years and have up to three broods during their lives.

Why Pillbugs Are Considered Pests
The good news is that pillbugs will not sting or bite. Nor will they transmit any diseases. Instead, it is just their presence that makes them be considered pests. It is also possible for pillbugs to enter buildings in large numbers, making their presence known and causing a serious nuisance. Although pillbugs spend a great deal of time outside, it is also common for these insects to invade homes, crawling underneath patios and foundations. They can also get into the ground floor of homes, crawl spaces, and damp basements. In these cases, pillbugs usually enter via the door threshold, voids from concrete block walls, and expansion joints. Even in the garden, there is a minimal risk of damage to your plants from pillbugs, although there is some risk. In the case of larger numbers, they may feed on the smaller roots or the part of the plants at ground level. The direct damage will typically be minimal, but their feeding can open up a way for fungi or bacteria to enter the plants. That, in turn, can lead to issues in the garden, including rot.

Methods for Controlling Pillbugs
Controlling pillbugs in the home begins with an inspection to determine how they have gotten inside. Make sure there are no openings or cracks in your foundation wall, and if there are, seal them up. Do the same by the bottoms of your basement windows and the doors. If necessary, you should seal up expansion joints. Unsurprisingly, professional control of pillbugs will also involve pesticides. A professional can apply insecticides along the baseboards of your home. Most pillbugs that end up in your living room and other non-moist spaces will die from that low moisture. In this case, you just remove them with a vacuum or broom.

Insecticides are typically necessary for larger infestations. In this case, the chemicals can reduce the number of pillbugs that move inward. You can also apply the insecticide outside, including by the entrances to the crawl spaces, the foundation’s vents, utility openings, and the bottom of exterior doors. If you have ornamental plantings or mulch beds, consider treating the ground next to these and the foundation. The appropriate insecticides for pillbugs can be applied in various forms, including sprays and liquids. Choosing the right insecticide requires care. If you are applying it indoors, ensure that it is safe to do so. If you are applying the insecticide outside or to control pillbugs in a garden, ensure that it will not harm the plants or the beneficial insects in your garden.

DIY Tips for How to Get Rid of Pillbugs
The best long-term solution for dealing with pillbugs will be to reduce hiding spots by the foundation as well as the moisture in and around the home. Get rid of locations that will attract pillbugs, such as grass clippings, leaves, and large accumulations of boxes, stones, boards, and mulch. If you cannot remove the items, then at least elevate them off of the ground. Minimize moisture by preventing water from accumulating by your crawl space’s foundation. Instead, ensure that your gutters, splash blocks, and downspouts function properly so the water gets diverted from your foundation wall. Inside the home, repair air conditioning, water pipes, and leaking faucets. You should also make adjustments to your lawn sprinkler if necessary to further minimize the risk of puddling.

If your house has poor drainage, you might need to get drains or tiles installed or adjust the slope of the ground. Make sure the basement and crawl space have low humidity via sump pumps and sufficient ventilation. Sometimes, pillbugs will invade the garden that you are working hard to maintain, causing a nuisance there. In this case, you should repot any plants that are in infested soil. This process should include scraping off the infected soil. If you have pillbugs inside the home, you can remove them using a vacuum so you do not have to contact the insects. In small numbers, you can trap them with a hollowed-out potato or half a cantaloupe placed upside down close to the location of the bugs. There are also other environmentally-friendly control methods, such as diatomaceous earth and Neem oil.

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