Bugs You'll Meet on Trails: 14 Types and What to Do
Bugs You'll Meet on Trails are one of the most common identification questions we get. Here are 14 you are likely to see.
Quick list
How to narrow it down
Narrow it down with three quick checks. Count the legs: insects have six, spiders and ticks have eight, and centipedes and millipedes have many more. Check for wings, even folded ones. Then compare size against a coin: a US penny is 19 mm across. Our bug identifier tool does this filtering for you.
The 14 bugs
American Dog Tick
American Dog TickDermacentor variabilisA brown tick with ornate white-gray markings on its shield, common along trails, roadsides and grassy fields. It readily feeds on dogs and people.
Tell-tale sign: Brown body with silvery-white mottling on the shield. Risk: American dog ticks can transmit Rocky Mountain spotted fever and tularemia.
Black Widow Spider
Black Widow SpiderLatrodectus mactansA shiny black spider with a red hourglass on the underside of its round abdomen. It builds messy, tangled webs in woodpiles, sheds, meter boxes and outdoor furniture.
Tell-tale sign: Glossy black, globe-shaped abdomen. Risk: Females have venom that can cause severe muscle pain and cramps; seek medical care after a bite.
Blacklegged Tick
Blacklegged TickIxodes scapularisAlso called the deer tick, a small tick with a dark shield and, in adult females, a reddish-orange rear body. It waits on grass and brush to latch onto passing people and animals.
Tell-tale sign: Dark black legs and shield. Risk: Blacklegged ticks transmit Lyme disease, anaplasmosis and babesiosis; remove attached ticks promptly.
Lone Star Tick
Lone Star TickAmblyomma americanumAn aggressive, reddish-brown tick of the Southeast and East; adult females have a single white spot on the back. All life stages bite people.
Tell-tale sign: Single white dot on the back of adult females. Risk: Lone star tick bites are linked to ehrlichiosis and alpha-gal syndrome, a red meat allergy.
Chigger
ChiggerTrombiculidae familyThe nearly invisible red larva of a harvest mite that attaches to skin in grassy, brushy areas. Chiggers feed on skin cells, not blood, and cause intensely itchy red bumps.
Tell-tale sign: Microscopic red or orange specks, barely visible. Risk: Chigger bites itch for days, but in the US chiggers don't transmit disease.
Horse Fly
Horse FlyTabanus spp.A large, stout fly with huge eyes that pursues people, horses and cattle for blood. Females slice skin with blade-like mouthparts, causing a sharp, painful bite.
Tell-tale sign: Large, heavy body with very large, often iridescent eyes. Risk: Horse fly bites are painful and can swell; they rarely transmit disease to people in the US.
Carpenter Ant
Carpenter AntCamponotus pennsylvanicusA large black ant that nests in moist or damaged wood, including window frames, decks and wall voids. It doesn't eat wood but excavates smooth galleries and pushes out sawdust-like debris.
Tell-tale sign: Large ant with an evenly rounded, single-arch thorax. Risk: Carpenter ants can deliver a painful bite and weaken wood over time, but they do not carry disease.
Eastern Subterranean Termite
Eastern Subterranean TermiteReticulitermes flavipesThe most widespread termite in North America, living in underground colonies and reaching wood through mud tubes. Dark, winged swarmers emerge indoors on warm spring days.
Tell-tale sign: Creamy white, soft-bodied workers in soil and wood. Risk: Termites don't bite people but can cause costly structural damage over time.
Spongy Moth
Spongy MothLymantria disparFormerly called the gypsy moth, an invasive moth whose hairy caterpillars strip the leaves from oaks and other hardwoods. Caterpillars carry paired blue and red dots along the back.
Tell-tale sign: Hairy caterpillars with five pairs of blue dots and six pairs of red dots. Risk: Caterpillar hairs can cause itchy rashes, and heavy outbreaks strip trees of their leaves.
Eyed Click Beetle
Eyed Click BeetleAlaus oculatusA long, gray-and-black beetle with two large, eye-like spots on its thorax. When flipped over, it snaps a hinge on its body and launches itself into the air with an audible click.
Tell-tale sign: Two large black false eyespots ringed in white. Risk: Eyed click beetles are harmless; the eyespots are a bluff to scare predators.
Firefly
FireflyPhotinus pyralisA soft-bodied beetle that flashes a yellow-green light from its abdomen on summer evenings. Each species uses its own flash pattern to find mates.
Tell-tale sign: Pink or red shield on the thorax with a black center spot. Risk: Fireflies do not bite or sting, but they contain chemicals that are toxic to lizards and some pets if eaten.
Harvestman
HarvestmanOpiliones orderOften called daddy longlegs, a long-legged arachnid with a single fused, oval body and no venom glands. It scavenges on dead insects, fungi and plant matter.
Tell-tale sign: One round body section instead of two. Risk: Harvestmen have no venom and no silk; they are completely harmless.
Luna Moth
Luna MothActias lunaA large, pale lime-green moth with long, sweeping tails on its hind wings. Adults don't eat and live only about a week to mate.
Tell-tale sign: Pale green wings with long, curved hindwing tails. Risk: Luna moths are completely harmless; adults have no functional mouthparts.
Periodical Cicada
Periodical CicadaMagicicada septendecimA black cicada with red eyes and orange wing veins that emerges by the millions every 13 or 17 years. Males fill forests with a loud, pulsing chorus.
Tell-tale sign: Black body with bright red eyes. Risk: Cicadas don't bite or sting; egg-laying can damage branch tips on young trees.
Which ones should you worry about?
6 of the 14 bugs in this guide can bite or sting. The ones to take seriously are American dog tick, black widow spider, blacklegged tick and lone star tick. The rest are harmless or simply a nuisance.
Frequently asked questions
What is the most common one?
Among the bugs in this guide, the American dog tick and black widow spider are the ones people ask about most.
Which of these are dangerous?
American Dog Tick, Black Widow Spider, Blacklegged Tick and Lone Star Tick can be medically significant.
How can I identify a bug I found?
Use the free bug identifier tool: choose the number of legs, wings, main color, size and where you found it, and it will list the closest matches.