Springtails (Order Collembola). Springtails are minute, primitive insects that can occur in enormous numbers (50,000 per cubic foot) in forest litter and organic soils. Springtails can be found outdoors in any moist situation, usually feeding on algae, fungi and decaying vegetation. Springtails are extremely sensitive to moisture, if their normal environment becomes dry, they will actively seek moisture, sometimes invading homes and similar structures where they are most commonly found near sources of moisture such as kitchens and bathrooms. These insects are not known to bite or cause damage to stored food, wood or fabrics. Possible reasons springtails are indoors include a new house with tight construction; the outdoor grade drains toward the house; broken or leaking plumbing; a wet crawl space, basement and/or landscape; an indoor humidifier; roof leaks; and more. Springtails can persist indoors if adequate moisture is found and if fungi, mildew or decaying vegetable matter exist in sufficient quantities, but in general, they are only occasional or incidental visitors in structures. If springtails persist indoors, the best control is to do everything possible to prevent their entry from the outside, decrease the humidity and moisture, and remove anything found to be moldy or in a state of decay. Here are some suggestions in addition to repairing the underlying source of water/excess moisture: 1. Remove wet, moldy wood or other wet moldy stuff from inside and under the house. 2. Run fans and dehumidifier 24 hours a day until the interior dries, then use as needed. 3. Create a 12- to 18-inch air space between the house walls and outdoor plants 4. Adjust outdoor irrigation (sprinklers; drippers or soakers) to maintain a dry area adjacent to the house. 5. Pull mulch away from foundation; replace with a 12-to 18-inch wide, 2 inches deep, gravel mulch. 6. Re-locate firewood wood, scrap lumber, or other items currently stored close to the house. In the meantime, vacuum as needed to decrease the population to a tolerable level. Some springtails appear to be quite resistant to insecticides. Several people have reported they have been unable to control springtail invasions with insecticides, even with multiple applications by professional pest control companies. Widely available insecticides like Sevin, cyfluthrin (sold as Bayer Advanced Home Insect Control) and bifenthrin (sold as Ortho Home Defense) have in some cases failed to reduce springtail populations. You can try treating the exterior walls and foundations with these products but do not be surprised if your springtail problem continues unabated. Be sure to read and follow all instructions on the label before using any pesticide.