Rollie pollies, often called pill bugs, woodlice, or sowbugs, are common residents in gardens and natural environments. While they primarily contribute positively to ecosystems, their presence can sometimes become a concern for homeowners and gardeners. This article explores their ecological contributions, instances where they become problematic, and strategies for managing their presence.
Ecological Contributions
Pill bugs are terrestrial crustaceans, more closely related to shrimp and lobsters than to insects. They are detritivores, as they primarily consume decaying organic matter such as dead leaves, wood, and other plant debris. This feeding habit positions them as important agents in natural decomposition.
Their consumption breaks down decaying material, allowing fungi, protozoans, and bacteria to further process it. This activity aids nutrient cycling, returning essential nutrients like nitrates and phosphates to the soil, supporting healthy plant growth and soil fertility.
Beyond decomposition, pill bugs’ burrowing activities contribute to soil aeration. Their movement through the soil helps to loosen it and improve its structure, which can benefit plant root growth and overall soil health. This aids in creating a more hospitable environment for other beneficial soil organisms.
Pill bugs also play a role in the broader food web. They serve as a food source for various animals, including birds, frogs, toads, lizards, spiders, and small mammals, supporting diverse garden wildlife and a balanced ecosystem.
Pill bugs can sequester heavy metals from soil. They take in heavy metals like lead, cadmium, and arsenic, crystallizing these ions in their guts. This process helps to clean up soil pollutants and prevents toxic metal ions from leaching into groundwater.
When They Become Problematic
While primarily beneficial, pill bug populations can sometimes surge, leading to garden issues. In large numbers, or when decaying organic matter is scarce, they may feed on tender plant parts. This can include vulnerable seedlings, young shoots, or ground-contacting fruits such as strawberries.
Damage to living plants occurs in conditions of high population density or when the garden lacks sufficient decaying material. They might also target plants weakened by disease or other pests. While not destructive enough to wipe out entire plants, their feeding can stunt growth or damage crops, especially in greenhouses where conditions are often ideal for their proliferation.
Pill bugs sometimes wander into homes, seeking moisture and shelter. They often enter through ground-level openings like gaps under doors, cracks in foundations, or unsealed vents. Once inside, they tend to congregate in damp areas such as basements, crawl spaces, or bathrooms.
Pill bugs do not bite, sting, carry diseases, or harm humans or pets. They also do not infest food, wood, or cause structural damage to homes. Their indoor presence is generally a nuisance, indicating an underlying moisture issue, as they typically dehydrate and die within days without a damp environment.
Strategies for Coexistence
Managing pill bug populations involves addressing conditions that promote excessive thriving. Reducing moisture is key; water plants in the morning so soil dries by night, when pill bugs are most active. Improving garden bed drainage and avoiding overwatering also helps.
Clear organic debris directly around plants or structures to reduce hiding and breeding sites. This includes removing fallen leaves, grass clippings, and thick mulch from plant bases or foundation areas. Elevating items like firewood also minimizes their habitat.
For vulnerable plants, physical barriers offer protection. Place simple collars made from paper, cardboard, or duct tape around young seedlings. Raised beds or elevating fruits off the ground with coarse mulch or supports also deters them from feeding on crops.
Encouraging natural predators like birds, frogs, and toads helps keep pill bug populations in check within the garden ecosystem. Creating a diverse garden environment that attracts these beneficial animals supports natural balance.
To manage indoor pill bugs, focus on moisture control and sealing entry points. Fix leaky pipes, improve ventilation, and use dehumidifiers in damp areas like basements or crawl spaces to reduce humidity. Seal cracks and gaps around foundations, windows, and doors to prevent entry. If found indoors, simply sweep or vacuum individual pill bugs.