Rolly pollies, also known as pill bugs or woodlice, are terrestrial crustaceans, often mistaken for insects, and are more closely related to shrimp and lobsters. They thrive in dark, damp environments, frequently found beneath rocks, decaying leaves, logs, or garden mulch. Rolly pollies play a role as decomposers in their ecosystems, breaking down organic matter.
Are Rolly Pollies Harmful to Humans or Pets?
Rolly pollies do not pose a threat to humans. They lack the ability to bite, sting, or pinch, and they do not produce any toxins that could cause harm. Their mouthparts are designed for consuming decaying organic matter, not for piercing skin. When disturbed, their primary defense mechanism involves curling into a tight, protective ball, which is how they earned the common name “roly-poly.”
These crustaceans do not transmit diseases to humans or pets. For household pets like dogs and cats, rolly pollies are generally harmless. If a dog were to ingest a rolly polly, it is not considered toxic, but the bitter taste might cause minor symptoms such as excessive drooling or vomiting. In rare instances, consuming a large quantity of these creatures could potentially lead to a hard mass, known as a bezoar, forming in a dog’s stomach, which would require veterinary attention.
Rolly Pollies and Your Garden
In garden environments, rolly pollies typically serve as beneficial decomposers. They primarily consume decaying plant matter such as dead leaves, rotting wood, and other organic debris. This feeding habit contributes to soil health by accelerating the decomposition process and returning valuable nutrients to the earth. They also contribute to soil aeration as they move through the ground.
A unique characteristic of rolly pollies is their ability to absorb and crystallize heavy metals like lead, cadmium, and arsenic within their guts, helping to remove these substances from the soil. While generally beneficial, rolly pollies can occasionally become a minor nuisance in gardens, particularly when their populations are high or when preferred decaying food sources are scarce. Under such conditions, they might feed on tender seedlings, young plant roots, or soft fruits like strawberries and squash, especially those in contact with the ground. However, significant damage to established plants is uncommon, as they generally prefer non-living plant material.
How to Handle Rolly Pollies
If rolly pollies become abundant or enter living spaces, several non-harmful management strategies can be employed. Since they require moisture to survive, improving drainage around foundations and reducing overly wet conditions in gardens can help deter them. Removing excess leaf litter, decaying wood, and thick mulch around the home’s perimeter eliminates their preferred damp habitats and food sources.
To prevent indoor entry, sealing cracks in foundations, around windows, and under doors can be effective. If found inside, rolly pollies typically do not survive long due to the drier indoor environment, and they can simply be relocated outdoors. For garden areas where they are causing minor damage, traps made from potato halves, cantaloupe rinds, or shallow dishes of beer or yeast water can attract and capture them. Applying food-grade diatomaceous earth around affected plants can also create a physical barrier that deters them.