Tennessee’s diverse landscapes, from the Appalachian Mountains to the Mississippi River, create varied habitats that support a wide array of insect species. This rich biodiversity includes numerous insects that frequently interact with humans, ranging from common household pests to those found in outdoor environments. The state’s climate, characterized by warm, humid summers and mild winters, contributes to a thriving insect population throughout much of the year.
Insects Commonly Found Indoors
Many insect species adapt to indoor environments, seeking shelter, food, or moisture within Tennessee homes and buildings.
Odorous house ants, small dark brown to black ants about 1/16 to 1/8 inch long, are a frequent indoor invader. They are known for releasing a “rotten coconut” smell when crushed, and they often establish nests in wall voids near heat or moisture sources. These ants forage for sweets and proteins.
Pavement ants, which are light to dark brown or blackish with distinct parallel lines on their head and thorax, are another common indoor pest. They typically nest under sidewalks, driveways, and foundations, but they will venture indoors for food, contaminating food sources as they forage. Pavement ants are approximately 1/8 inch long and can be found nesting in walls, insulation, or under flooring.
Common house spiders, measuring up to 3/8 inch, are frequently seen indoors, weaving tangled webs in corners, basements, and attics. These spiders are generally harmless to humans and consume other small insects like flies and moths, making them beneficial for pest control.
Cellar spiders, often recognized by their small bodies and long, thin legs, also inhabit damp areas like basements, crawl spaces, and garages, where they build messy webs and prey on other spiders and insects.
Outdoor Pests and Biting Insects
Tennessee’s outdoor environments are home to several insect species that can be considered pests, particularly those that bite or sting.
Mosquitoes are widespread, with over 200 species in the United States, and about 12 of these can transmit pathogens to humans. Common species in Tennessee include the Culex mosquito, Asian tiger mosquito, and yellow fever mosquito, which can carry diseases such as West Nile virus, La Crosse Encephalitis, and Eastern Equine Encephalitis. Mosquitoes are typically active from spring through fall, and they lay their eggs in still water.
Ticks are another concern, with several species present in Tennessee, including the American dog tick, Lone Star tick, and blacklegged tick. American dog ticks, identifiable by their reddish-brown color with white or gray markings, are active from spring to summer and can transmit Rocky Mountain spotted fever and tularemia. Lone Star ticks have a white spot on the female’s back and are active from April through July, capable of transmitting ehrlichiosis, tularemia, and causing Alpha-gal syndrome, a red meat allergy. Blacklegged ticks are vectors for Lyme disease and are active year-round when temperatures are above freezing. Ticks are typically found in wooded, brushy, or grassy areas.
Stinging insects like wasps and hornets are also present. The European hornet, a large brownish insect with dull orange stripes, and the bald-faced hornet, which is black with white markings, are two types found in the state. European hornets can be active at night and build nests in hollow trees or wall voids. Bald-faced hornets construct large, paper-like nests in trees or on buildings and are highly defensive.
Beneficial and Notable Insects of Tennessee
Beyond pests, Tennessee is home to many insects that play an important role in the ecosystem or are culturally significant.
Honey bees, for instance, are recognized for their agricultural importance as pollinators of various crops, wildflowers, and forest plants. The state’s Department of Agriculture actively supports beekeeping to maintain healthy honey bee populations due to their role in food production, contributing significantly to the state’s agricultural economy.
Ladybugs are another beneficial insect, serving as natural predators of aphids and other garden pests, thereby helping to protect plants without chemical intervention. These small beetles are easily recognizable by their typically round, dome-shaped bodies and vibrant colors, often red or orange with black spots. Their presence in gardens indicates a healthy ecosystem.
Fireflies, often called lightning bugs, are notable for their bioluminescent displays, particularly on warm summer evenings. These beetles produce light through a chemical reaction in their lower abdomen, creating a unique natural spectacle. Different species have distinct flash patterns.
Cicadas, known for their periodic emergence and loud buzzing sounds, are also a distinctive part of Tennessee’s insect fauna. These insects spend most of their lives underground as nymphs, feeding on tree roots, before emerging as adults to mate. Their synchronous appearances, particularly of periodical cicadas, are a remarkable natural event.