Pill bugs are also known as roly polies. They are terrestrial isopods with a round-backed or flattened profile, sharply angled antennae, and seven pairs of legs. Some species can roll into a ball when they feel threatened or disturbed.
Pill bugs are not insects. They are crustaceans with jointed limbs, hard outer shell, and segmented trunk. Armadillidium vulgare refers to the common pill bug’s scientific name.
There are approximately 12 species of roly polies found in central and northern United States. Four species are found in South Dakota. Several other species have been recorded from the wetlands of Florida and coastal habitats.
They can be distinguished using a hand lens. Practice will make it easier to tell the species apart without using any tools.
- Porcellio spinicornis has characteristic markings. They have a broad, flattened body and a dark brown head. Their back has a dark central stripe.
- Cylisticus convexus can roll into balls when disturbed. The top surface of their body is dark, gray-black, and glossy with pale, transparent streaks.
- Porcellionides pruinosus has long antennae with characteristic white joints. It’s a slender species that is 0.2" to 0.4" long. Porcellionides pruinosus is light gray and has whitish legs.
- Trachelipus rathkei can be dark gray or rusty brown in colour. It’s the most common species of pill bug. Trachelipus rathkei is flattened and broad. It ranges from 0.3" to 0.6" in length. The body of trachelipus rathkei forms into a C when it’s disturbed.
Diet of Pill Bugs
· Organic Material
Pill bugs mainly feed on decaying or dead organic material. They primarily eat dead vegetable matter like grass and leaves. These bugs eat rotting wood, algae, moss, fungi, bark, mold, young plants, leftovers, mulch, and damp vegetation.
These crustaceans are decomposers that help return important nutrients to the soil. Other organisms further digest the nutrients. This process helps plants get the nutrients they need.
· Fruits and Vegetables
They tend to consume ripe fruits and vegetables that are touching the ground. If their number becomes too large, they may also eat living plants. Due to this, they are called pests. This kind of damage happens only in rare situations.
They shouldn’t be seen as pests. Rollie pollies may eat the stems and roots of various plants occasionally, but they cause minimal damage to live foliage.
· Fecal Matter
Pill bugs eat fecal matter as well. They consume their own poop to make up for the amount of copper they lose every time they defecate.
They need copper to survive and eating their own poop allows them to reuse it. If they don’t have enough copper, they get sick and they turn purple or bright blue in colour.
· Stink Bug Eggs
Pill bugs may eat the eggs of stinkbugs as well. Stink bugs cause significant damage to crops and pill bugs can help in controlling this problem.
Pill bugs are not fussy eaters. They can survive on decaying organic matter and some of their feeding habits can benefit the environment.
Though it is unlikely for you to turn them as pets, there are a lot of people keep pill bugs as pets. If you want to do this too, you can give pill bugs fresh vegetables and fruits like lettuce, the skin of apple and carrots.
You can also give them fish food, the skin of zucchini, potato, cardboard, oatmeal and crumpled egg cartons. Water can be added to their diet as well.
Overall, they can be treated as pests and at the same time help your foliage. However, when you notice them in large populations, it is only necessary that you get rid of them.
Significance of Pill Bugs
Pill bugs are an important part of the decomposer fauna together with snails, millipedes, and earthworms. These animals help return organic matter such as decaying plants to the soil where it’s further digested by protozoans, bacteria, and fungi.
Thanks to this process, vital nutrients such as nitrates and phosphates become available to plants. Pill bugs occasionally eat roots, but they shouldn’t be viewed as pests because the damage they cause to live vegetation is only minimal.
Pill bugs are significant in sites like slag heaps and coal spoils contaminated with heavy metal. They can take in heavy metals like zinc, cadmium, and copper.
These crustaceans crystallize heavy metals as a spherical deposit. They eliminate a large amount of toxic metal ions found in the soil. Due to their high tolerance to toxic metal ions, they survive where other species can’t and help restore contaminated areas by expediting topsoil formation.
This is favourable to plants that help stabilize the soil through root formation. Toxic dust can be reduced and metal ions won’t leach into the ground water when the soils are stabilized.
Rollie pollies can be found in humid areas. They live in damp locations like in pine straw, behind bark, under leaf litter, in compost piles and organic landscaping materials.
It is common to find large numbers of pill bugs under potted plants, rubble, and logs. Pill bugs can be kept in cardboard boxes, but the moist substrate will eventually cause the boxes to deteriorate.
If you want to keep pill bugs as pets, it is best that you keep them in a glass aquarium or plastic tub. Make use of a substrate that’s capable of holding humidity.
You can use about 1" of moist soil, hummus, or peat moss. Put a thin layer of bark or leaf litter on top of your preferred substrate and then cover it with a chunk of bark or wood.
Humidity and Lighting
Pill bugs are easy to maintain. There’s no need to install extra heating in your home, but you do have to make sure that there’s a high level of humidity in the area where you’re going to keep the bugs. Mist the container every day to keep the substrate damp, but don’t soak it.
You can use a humidity gauge to monitor the level of humidity. Maintain the humidity level above 75% percent. Pill bugs are capable of absorbing the water vapour from the environment at 85%. This helps them stay hydrated. Pill bugs will not survive without proper humidity.
They are active at night because they are nocturnal. You don’t need to install specialized UV lighting to ensure their survival. If you wish to replicate a day and night situation, you can use a coil light bulb and a clamp light. Use a timer so that the lighting automatically turns off after ten to twelve hours of daylight.
How to Control Pill Bugs
Pill bugs can live for 3 years in the best conditions. They may enter your home through crawl spaces or damp basements, but they will only stay alive if there’s moisture in the area.
These crustaceans become a nuisance once they start causing damage to plants due to their feeding habits. Prevention starts outdoors. Remove items that hold moisture like rocks, leaf litter, wood debris, grass clippings, and debris from points of entry such as basement windows and foundation walls.
Here are other tips on how to control and get rid of pill bugs.
- Water your lawn in the morning so it will be dry by the afternoon.
- Store firewood off the ground.
- Ventilate crawl spaces and basements to get rid of excess moisture.
- Drain moist areas and standing water near potential entry points.
- Fix and seal openings and cracks around doors and basement windows as well as in the foundation walls with weather stripping and caulking compound.
- Spray residual insecticides along cracks and crevices and other entry points.
- Pill bugs can be found in groups, especially under items that have gotten damp from sitting. Since they eat organic matter, they may visit these areas to find food.
Insecticides will not be very effective once the pill bugs enter your home. You can control these bugs by sweeping and vacuuming them when seen. Moisture inside the house should be controlled as well.
If the bugs have not entered your home yet, a perimeter application of insecticides made for pill bugs can be done. This can help you keep the bugs out of your property.
You can apply an insecticide around crawl spaces, utility openings, foundation vents, up underneath siding and along the bottom of all exterior doors. It’s also a good idea to spray insecticide beside the foundation in ornamental plantings and mulch beds.
A heavy buildup of leaf litter and mulch should be raked back to look for and expose pests. Insecticides may also be sprayed along the foundation walls of unfinished basements and damp crawl spaces.