Care guide
Springtails in the Basement or Crawl Space
Everywhere else, springtails are a nuisance you can ignore. In a basement or crawl space they are worth reading as information.
Springtails are tiny soil arthropods, usually under 2 mm. They are named for the furcula — a forked appendage folded under the abdomen that snaps down and flings the animal several times its own body length. That jump is why they get mistaken for fleas, and it is the single biggest source of confusion about them.
They do not bite, do not sting, do not carry disease, and do not damage buildings, furniture or stored food. They eat mould, fungus and decaying organic matter.
What They Are Telling You
Springtails eat mould and need sustained moisture. A persistent population under the house means both are present. The springtails are harmless; sustained damp and mould in a structure are not, and they cost money the longer they run.
Common sources:
- Ground moisture coming up through an unsealed crawl space floor
- Grading that slopes toward the house, or downspouts discharging at the foundation
- Condensation on cold pipes and ducts in a humid space
- A slow plumbing leak in an area nobody visits
- Damp cardboard or stored paper, which holds water and grows the mould they eat
The Order to Fix It In
- Deal with water outside first — gutters, downspouts, grading. Nothing indoors holds while water is being delivered to the foundation.
- Vapour barrier over bare crawl-space soil. This is usually the single biggest change.
- Dehumidify what remains.
- Get rid of damp cardboard storage. Plastic bins instead.
- Then reassess. The springtails go when the damp does.
If there is visible mould over a large area or the structure feels soft, that is a job for someone who inspects buildings.
They Are a Symptom, Not the Problem
This is the part most pest advice skips. Springtails need moisture to survive and die quickly without it. A population indoors is telling you there is damp somewhere — and that is the actual problem.
Spraying them achieves very little. You kill the ones present, the damp remains, and a new population arrives. Find the water and the springtails leave on their own.