Pests of The Season

SUMMER

During the warmest months of the year, several of the pests that appeared in spring become more obvious as they multiply in and around our homes/offices. The nuisance social insects include pavement ants, odorous house ants, pharaoh ants, small honey ants, carpenter ants, acrobat ants, paper wasps, yellowjackets, baldfaced hornets, and bumble bees. Any carpenter bee and small solitary bee entry holes not treated in spring will show sporadic or renewed activity during summer. Although the unsightly nests and activity of mud daubers make them a nuisance, these wasps usually are not aggressive.

Warm weather allows several pest species of beetles and moths to enter our residences and workplaces and establish breeding populations in our food and personal property. Among those insects which infest dry processed (packaged) and unprocessed foods, ingredients and seeds are the Indianmeal moth, red & confused flour beetles, sawtoothed grain beetle, rice & granary weevils, drugstore beetle, cigarette beetle, spider beetles and larder beetle. The insects known to infest items made of wool, felt, fur, hair, hide and feathers include the webbing clothes moth, casemaking clothes moth, black carpet beetle, varied carpet beetle and hide beetle. These same insects also breed in taxidermy specimens as well as in the dried remains of animals that died inside our homes/offices and workplaces. Open or poorly sealed wood buildings may be infested by anobiid powderpost beetles (which prefer soft woods / lumber) and lyctid powderpost beetles (which prefer hard woods / flooring).

Several species of flies become problematic during the summer. Blow flies, especially blue and green bottle flies, may become an issue indoors if even one female fly discovers a dead animal in an attic, chimney or structural void and lays her eggs on the “fresh” carcass. House flies readily breed in moist garbage that contains discarded food, as well as in animal (dog and livestock) manure on the premises. Small fruit flies (vinegar flies) breed in fermenting fruits, vegetable matter, juices, syrups, and moist baking ingredients that escape our attention during the clean-up process. Other small flies that infest structures are the moth flies (a.k.a. drain flies / sewer flies) and phorid flies (a.k.a. humpbacked flies / scuttle flies), which breed in the scum (“biofilm”) and other decaying organic matter that builds up in floor drains, sink traps, urinal traps and waste lines. Tiny fungus gnats (especially darkwinged fungus gnats) readily breed in the fungus that grows in the soil and roots associated with over-watered potted plants, as well as in over-irrigated planting beds and mulch around structures.

Among the biting flies we encounter on our property are several species of mosquitoes (which breed in shallow, still pools of standing water and various rain-filled containers), stable flies (which breed in piles of moist grass clippings, bales of hay, wet straw and incorrectly composted plant material), and deer & horse flies (which aggregate near their livestock host animals and breed in marshy wetland areas).

Some insect pests are present because of high levels of moisture in and around our homes/offices and workplaces. This retained moisture results in the growth of fungus/mold on such materials as wood, cardboard, paper, drywall, and decaying plant matter and provides most of the sustenance required by springtails, booklice (a.k.a. barklice / psocids), foreign grain beetles (actually a fungus-feeding beetle) and fungus gnats (mentioned above).

Accumulations of moist mulch and dense vegetation around buildings, as well as landscaping stones and timbers around buildings are conducive to the presence of millipedes, sowbugs & pillbugs, common invasive spiders, centipedes, silverfish, field crickets, earwigs, ground beetles, eastern subterranean termites and ants (see above). Oriental cockroaches (a.k.a. “waterbugs”) harbor beneath old cracked pavement in urban and older suburban settings and Pennsylvania wood cockroaches sometimes use rustic buildings as harborages in rural and wooded settings. All of these so-called “perimeter invaders” or "occasional invaders” readily access our residences and workplaces via crevices and unsealed utility penetrations at or near the foundation. However, some of these pests are good climbers and may enter buildings through gaps and crevices in the exterior sheathing, eaves, soffits and roofing. 

Of course, opportunistic tree squirrels, bats, woodpeckers and unprotected nuisance birds continue to look for access points into building attics and structural voids all summer long. If birds are nesting in a building, there is a good chance that their main ectoparasite, the northern fowl mite, will enter living spaces/workspaces in numbers from adjacent nesting sites. Likewise, the presence of numerous bats in a building makes the appearance of their main ectoparasite, bat bugs, likely in living spaces/workspaces.

Lawns and planting beds may show increasing evidences of moles as well as the mound nests of field ants. Both raccoons and skunks are known to tear up lawns in the process of digging (“grubbing”) for insect larvae on which to feed. These same animals, joined by our native marsupial, the opossum, go dumpster-diving, overturn trash cans and visit outdoor pet food dishes to enhance their diet. Furthermore, these animals serve as secondary hosts to cat fleas and can introduce these biting insects to our homes/offices, yards and ultimately, our dogs and cats. Goundhogs (woodchucks) and chipmunks often dig unsightly burrows near/beneath foundations, patios, decks, outbuildings, and in lawns and gardens.

Congregations of Canada geese often cause cosmetic damage to lawns and landscaping around ponds and private lakes because of their unsightly droppings and their feeding damage to fleshy ornamental plants. Muskrats also cause bank erosion and cosmetic damage to vegetation growing along the edges of ponds and private lakes. Occasionally snakes become an issue in and around structures, especially near wooded areas, ravines, creek and riverbanks, and mainly rural settings.