Storing firewood without bringing pests inside

What comes out of firewood

• Longhorned and metallic wood-boring beetles develop in dying or freshly cut trees and may emerge indoors, but they won't attack the wood in your home.^[1][3]
• Bark beetles, small (under 1/8 inch) brown or black cylindrical beetles, are common in wood cut from dead trees; one log can hold hundreds.^[1]
• Pillbugs, centipedes, millipedes and ground beetles overwinter under bark and wake up when the wood warms. None will harm you or your home; just pick them up or vacuum them.^[1][3]
• Other things that overwinter under loose bark can ride in too: wood cockroaches, wasp or hornet queens, spider egg sacs, praying mantid egg masses and moth cocoons. They can't survive long indoors and won't multiply or become established in the home.^[3]

Why firewood beetles rarely move into the house

The beetles most often found developing in firewood are roundheaded and flatheaded wood borers and small brown to black powderpost (shothole) beetles. Kentucky's entomologists rate their potential to infest structural wood as very low: many attack only certain kinds of wood, such as hickory or oak, and they usually need far more moisture than the wood in a house holds. Adults that emerge indoors may gather at windows and light fixtures as they head toward light, but they are harmless.^[3]

Termites and carpenter ants

Termites can tunnel into wood stacked on the ground. Termites carried inside in firewood can't start a new colony, but a woodpile against the house can be a route into the structure.^[1]

Termite colonies live in the soil, so only workers are found in the wood, often along with the mud they use for their tunnels. Workers carried indoors die once they are cut off from the colony. The colony itself is most likely in the soil where the tree grew, unless the woodpile is old and has sat undisturbed a long time, in which case it may be in the soil under or near the pile.^[3][5]

Carpenter ants hollow out smooth galleries along the grain. Ants carried in may wander out of the wood as it warms, but the odds of them nesting in your house are very slim.^[1]

Carpenter ant galleries are very clean, with no mud or sawdust, unlike wood termites are working in, where their mud shows. Ants brought in on logs won't start an infestation, but a colony can live in an old woodpile outdoors. Termites and carpenter ants are most likely in wood that has been wet or stacked in one place for a long time.^[3]

Where and how to stack the woodpile

• Keep the stack off the ground. Off-ground wood dries better, is harder for crawling insects to get into, and is less likely to be infested by termites and ants.^[1][3][4]
• Keep the main pile away from the house. Don't stack wood in or against the house or other buildings for long periods, especially right beside the foundation. Nebraska Extension suggests keeping the bulk of the wood at least 30 feet from the house, mainly to keep mice and rats from using it as cover while they look for a way in.^[3][4][5]
• Rodents need very little room: a mouse can squeeze through a hole 1/4 inch across and a rat through a half-inch hole. The worst spot for a woodpile is against the house, and the next worst is beside a dog pen, where spilled food and water supply everything else a rat or mouse needs.^[5]
• Keep only a day or two of wood near the door and refill it from the main pile.^[5][3]
• Cover the pile to keep it dry, with a woodshed, an unheated garage or a sheet of plastic or metal roofing, leaving an air space between wood and cover. Covering in summer and fall also keeps out some of the creatures looking for a place to overwinter.^[5][3]
• Burn the oldest wood first, since it is the most likely to be infested, and don't stack new wood on top of old.^[3]

Bringing wood inside

• Check each piece as you pick it up, especially surfaces that were on the ground or against other pieces. Knock pieces together sharply to shake loose what you can't see and brush off webbing or cocoons before you carry the wood in.^[4][3]
• Keep the wood cold until you burn it. Insects in wood kept below about 50 degrees stay dormant; once wood warms indoors for a couple of days or more they become active and crawl out. Bring in only what you will burn in a day or so, and keep it somewhere cool such as a porch or garage until then.^[5][1][3]
• If a piece has big black carpenter ants or termites in it, or you just don't want the insects inside, take that piece back outdoors. Insects that do emerge indoors can be vacuumed up or swatted and thrown out.^[5][3]

Burn it, don't spray it

Iowa State, Kentucky, Illinois and Nebraska extension all advise against putting insecticide on firewood. Most insecticides don't reach the insects deep in the wood, so there is little benefit, and burning treated wood indoors can vaporize the insecticide into the living area or produce fumes. Nebraska's advice: if you don't want the insects, take that piece back outside rather than spraying it and burning it in the house.^[1][3][4][5]

Don't move firewood long distances

Moving firewood can carry invasive insects that kill trees to new areas. Get it locally, buy certified heat-treated firewood, or gather it on site where permitted.^[2]

Tree-killing insects and diseases hitchhike in firewood and can travel farther in one weekend than they would in years on their own. Many, including emerald ash borer, develop under the bark, and tiny eggs or fungal spores can sit in bark cracks, so wood that looks clean can still carry them.^[6]

Larvae and pupae inside moved firewood can keep developing until they emerge as adults and spread the infestation to nearby trees. USDA names Asian longhorned beetle, brown spruce longhorned beetle and emerald ash borer among the firewood pests its rules guard against.^[7]

Seasoned, dry wood is not automatically safe. Emerald ash borer has emerged from ash firewood at least two years after harvest, and oak firewood can carry oak wilt, a tree-killing fungal disease, so wood from a tree that can't host emerald ash borer can still carry other pests.^[6]

Quarantines, heat-treated wood and how far is too far

• Some states restrict firewood movement. Missouri, for example, has a statewide quarantine on moving hardwood firewood out of the state, and in Minnesota firewood from any hardwood tree is a regulated article that can't legally leave a quarantine area without a state certificate. The Don't Move Firewood site has a map of local rules.^[6][8][2]
• Missouri's conservation department recommends not moving firewood more than 50 miles from where it was cut, even if it looks pest-free and even if you'll burn it within a couple of days.^[6]
• Packaged firewood that has been heat-treated and labeled with the USDA shield is the only firewood Missouri considers safe to move. The federal standard heats the wood's core to 60 degrees Celsius (140 degrees F) for 60 minutes, which kills pests inside; Minnesota's certified heat-treatment program uses the same schedule.^[6][8][7]
• Bringing firewood into the United States from Canada? Only heat-treated wood is allowed, even a small amount for personal use: hardwood heated to 60 degrees Celsius (140 degrees F) at the core for 60 minutes, or softwood to 56 degrees Celsius (133 degrees F) for 30 minutes, with a treatment certificate or a commercial treatment label. Untreated wood may have to be disposed of before you cross.^[7]
• Already moved wood a long way? Burn all of it soon after you arrive so pests don't have time to leave it and find trees. Leftover campground wood is best left for the next camper rather than taken home. Spring and summer are the riskiest times to move firewood, because most pests emerge from wood during the warm months.^[6]

Common questions

Can termites in firewood infest my house?

Not from the wood you carry in. Termite workers brought indoors can't start a new nest and die away from their colony. The risk is a woodpile stacked against the house, which can give a colony in the soil a route into the structure.^[1][5]

Is old, seasoned firewood safe to move?

Not necessarily. Pests and fungal spores can survive in seasoned, dry wood for long periods; emerald ash borer has come out of ash firewood at least two years after it was cut. Heat-treated, labeled firewood is the safe choice for moving.^[6]

Should I spray my woodpile with bug spray?

No. Extension entomologists advise against treating firewood with insecticides: they don't penetrate far enough to help, and burning treated wood can release fumes into your home. Stack the wood off the ground and away from the house instead.^[1][3][4]

Sources

1. Iowa State University Extension and Outreach, “Firewood Insects (Yard and Garden, reviewed February 2020).” yardandgarden.extension.iastate.edu/encyclopedia/firewood-insects (accessed 2026-10-06)
2. The Nature Conservancy, “Don't Move Firewood.” www.dontmovefirewood.org/ (accessed 2026-10-06)
3. University of Kentucky Entomology, “ENTFACT-626: Firewood Insects.” entomology.ca.uky.edu/ef626 (accessed 2026-11-10)
4. University of Illinois Extension, “Firewood Tips for the Homeowner (Know How, Know More blog, 2016).” extension.illinois.edu/blogs/know-how-know-more/2016-01-23-firewood-tips-homeowner (accessed 2026-11-10)
5. Nebraska Extension in Lancaster County, “Don't Create a Firewood Haven for Rodents and Insects (2020).” lancaster.unl.edu/dont-create-firewood-haven-rodents-and-insects/ (accessed 2026-11-10)
6. Missouri Department of Conservation, “Don't Move Firewood.” mdc.mo.gov/node/250342 (accessed 2026-11-10)
7. USDA Animal and Plant Health Inspection Service, “Don't Be Delayed at the Border: Make Sure Your Firewood Is Heat-Treated (Program Aid 1999, revised June 2015).” www.aphis.usda.gov/sites/default/files/fs-heat-treat-firewood.pdf (accessed 2026-11-10)
8. Minnesota Department of Agriculture, “Heat Treatment Guide for Firewood.” www.mda.state.mn.us/plants-insects/heat-treatment-guide-firewood (accessed 2026-11-10)