Firewood Restrictions & Safe Handling Guidelines

Stay on the right side of the law with your firewood:

• Make sure that firewood you buy or sell in Minnesota is labeled with origin of harvest (MN Stat. 2010, Chapter 239, Weights and Measures)
  • Sale by Package: "… As of August 1, 2007, firewood sold or distributed across state boundaries or more than 100 miles from its origin must include information regarding the harvest locations of the wood by county and state on each label or wrapper." More…
  • Sale from Bulk: "… As of August 1, 2007, firewood sold or distributed across state boundaries or more than 100 miles from its origin must include delivery ticket information regarding the harvest locations of the wood by county and state." More…
  • Any firewood with origin of harvest from a quarantined area must have a federal shield documenting that the wood has been treated to destroy the quarantined pest.
  • How to buy firewood – Minnesota Department of Commerce
  • 6 questions to answer before buying firewood – University of Minnesota Forest Resources Extension
• Check with your destination before bringing firewood on a trip.

  • Restrictions exist on what firewood may be brought onto lands owned / operated by these entities (among others) in Minnesota:

    • DNR: It is against the law to bring unapproved firewood into any state park, state forest or day-use area (M.S. 89.551 Sec 2 Subd.3b). Approved wood can be obtained from DNR approved firewood vendors. More…
    • National Forests: The Chippewa and Superior National Forests prohibit firewood originating outside of Minnesota on their lands. More…
    • Voyageurs National Park: Only DNR approved firewood may be brought into the park. More…
    • Army Corps of Engineers Recreation Areas: Firewood must be obtained within 100 miles of site, or certified as pest free.
    • Many other public and privately owned camping and recreation areas in Minnesota have similar firewood restrictions in place. If you are unsure if your destination is one of them, plan to use local firewood or find out in advance of your trip whether it is ok to bring firewood.
• Check with your city before storing firewood.
  • Many municipalities have ordinances prohibiting the storage of elm logs with bark intact due to the risk of spreading Dutch elm disease.
  • Many municipalities also ban the storage of oak logs with bark intact from trees killed by oak wilt due to the risk of spreading oak wilt to new trees.
• Make sure you are not in a quarantined area before moving firewood.
  • All firewood (along with other outdoor articles) is quarantined for gypsy moth in the northeastern U.S. - map, quarantine
  • All hardwood firewood is quarantined for emerald ash borer in some areas of Minnesota and elsewhere in the U.S. – Minnesota Quarantine & Regulatory Information
  • All hardwood firewood is quarantined for Asian longhorned beetle in some areas of the U.S. – map, quarantine

Keep firewood from spreading pests and disease:

Use local firewood whenever possible.

• When you move firewood long distances you may be introducing an invasive pest into a new area.
• Remember that infested wood may not show visible symptoms.
• Use properly seasoned or otherwise treated firewood whenever possible.

  • Firewood must be dried to burn properly, drying can be accomplished by:

    • Seasoning (aging)

      • Seasoned firewood is less likely to contain damaging pests. Pests of living trees usually cannot survive in dried firewood.
      • In some cases, firewood should be covered during the spring and summer while seasoning.

    • Kiln drying

      • Kiln dried firewood may also be considered heat treated if temperature requirements have been met to kill pests.
      • Wood that is certified as heat treated by a government entity has been verified to have met temperature requirements.
  • Another way firewood is sometimes treated is by debarking.
    • Debarking will remove the threat of wood containing bark beetles or other phloem inhabiting pests provided all of the bark is removed.
    • If some sapwood is removed in addition to bark (1/2" of material total) then the wood can also be considered free of pests like emerald ash borer that tunnel into wood, but not deeply.
      • It can be difficult to tell if, and how much, sapwood has been removed from a log.
    • Debarking alone is not sufficient to make wood free of pests that tunnel deeply into the wood such as Asian longhorned beetle and Sirex woodwasp.
• If you take firewood with you on a trip, burn it all on that trip or bring it back home with you.
  • There is a risk that pests could emerge during the trip, particularly if the trip is long and is taken during a pest’s active period (generally spring and summer).

Handling firewood that may be or may become infested with pests:

• Many tree species have pests associated with them that may survive in cut wood and then emerge and infest nearby trees – particularly if those trees are stressed (see table below).
• Some trees have very damaging pests associated with them – special care should be taken when handling wood from these tree species (see table below).
• If you are in an area that is quarantined for a pest, you should consider all wood from that pest’s hosts infested and treat accordingly.
• If you suspect a tree or wood to be infested with a pest that is not known to be established in your area such as emerald ash borer, gypsy moth, Asian longhorned beetle or sirex woodwasp contact the "Arrest the Pest" hotline immediately:

"Arrest the Pest" Hotline
888-545-6684
Arrest.The.Pest@state.mn.us

• If you suspect a tree or wood to be infested with an established pest such as Dutch elm disease, oak wilt or another pest that could damage other trees in the area, follow these guidelines for handling the wood:
• If you don’t want to make firewood and only wish to protect other trees from the pest
  • Remove the tree and debark (only effective for some pests), burn, bury or chip the wood prior to insect activity (April 1 for oak wilt, May 1 for most others)
• If you want to make firewood and protect other trees from the pest:
  • Ultimately the pests contained in the wood will complete their lifecycle and emerge or die in the material from desiccation or other cause.
• You need to cover the material during spring and summer so that emerging insects can not escape the covering until no insects or too few to cause problems will be emerging.

  • Cover material with tarp or heavy plastic (6 mil) during period of insect activity – April 1 to August 1.

    • Clear plastic may also provide a solarizing effect – heating the wood and speeding the death of the infesting pests.
    • Bury cover edges in ground, make sure no holes in covering.
  • Material should be covered completely and loosely.
    • If the cover is stretched tight over wood, insects will chew through cover and escape. If cover is not tight against wood, insects will not be able to gain leverage to chew through the material.
• While woodborers (emerald ash borer, twolined chestnut borer, etc) will not attack cut wood, most bark beetles will.

  • By covering wood you are not only prohibiting insects from escaping, but also prohibiting the wood from becoming infested.

    • This is particularly important for elm as elm bark beetles vector Dutch elm disease.
• The more rapidly wood desiccates, the fewer pests will survive.

  • Unfortunately, covering firewood reduces the rate of drying.

    • Uncover firewood except during insect activity period.
  • Split and stack wood prior to covering to promote air flow and drying.
  • Stack wood in areas receiving sunlight to speed drying.
  • Stack wood away from other wooden structures to avoid problems with carpenter ants.
  • Bark beetles will not survive in covered firewood for more that one summer. Woodborers may survive in covered firewood for one, two or possibly three summers.
    • Every summer that wood is covered reduces the number of individuals that may emerge.
    • For many pests, one summer is adequate, for some pests two summers is better.

References

• Twolined Chestnut Borer
• Twolined Chestnut Borer - Management options
• Forest Insect and Disease Newsletter
• Petrice and Haack. 2007. Great Lakes Entomologist. Can EAB emerge from logs two summers after infested trees are cut. 40:92-95
• Petrice and Haack. 2006. Effects of cutting date, outdoor storage conditions, and splitting on survival of Agrilus planipennis in firewood logs. J Econ Entomology 99(3) 790-796
• Pine bark beetle management
• Products from dead or dying yard trees
• Oak Wilt in Minnesota
• Oak Wilt

Tree genera of Minnesota and pests of concern that may be contained in or on wood.

What's In That Wood Pile? (PDF)

MDA Contact

arrest.the.pest@state.mn.us
1-888-545-6684 
 
Invasive Species Abatement Program