TRANSFER, Pa. (WKBN) — You might have a long packing list for your summer camping trip, but there’s one thing you shouldn’t bring: firewood.

It’s not the wood that’s the real concern, it’s the invasive species the firewood may carry, said Bill Spring, with Shenango River Lake in Pennsylvania. The pests may be invisible to the naked eye, and hidden within the firewood.

Get Hawaii’s latest morning news delivered to your inbox, sign up for News 2 You

“Even though it may not look like it, firewood isn’t dead,” writes the National Park Service. “Live wood-boring beetles, tiny insect eggs, microscopic fungi spores, and more can be hidden in and on even the healthiest looking wood.”

Other pests that could be hiding in firewood include the emerald ash borer, which attacks ash trees, and the spotted lanternfly that’s invading the country.

Spring said bringing firewood from far away can spread these invasive pests to new areas, where they can damage native forests.

“These organisms cannot travel far on their own, but can travel hundreds of miles hidden within a firewood bundle in your car or RV,” the Park Service explains.

“We ask that you buy and collect firewood from the general region/area – usually within the county – that you’re recreating in,” Spring said.

Campers should also leave any remaining firewood at the campsite unless they live in the same county.

Get news on the go with KHON 2GO, KHON’s morning podcast, every morning at 8

The National Park Service also advises campers to check for fire restrictions or burn bans before they consider making a fire at all.