Foresters Offer Advice on Dealing with EAB

By Douglas Rooks, Editor

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     As the emerald ash borer (EAB) approaches the state, the Maine Forest Service (MFS) is preparing for likely quarantines, while foresters are hearing from and advising their clients about what the future may hold.

     Harold Burnett, whose Two Trees Forestry is based in Winthrop, works mostly in central Maine, and finds that many landowners are already knowledgeable. “I’m impressed by how many people are aware, and informed, about what’s happening in other states,” he said. “I’ll say ‘ash tree’ and they’ll say ‘emerald ash borer.’ ” Burnett said that “losing the species” in Maine is a real possibility, but that immediately cutting all ash from a woodlot is not likely the best response.

     Still, when a harvest is already planned, it only makes sense to focus on ash removal, including some trees that might not otherwise be part of the harvest plan. Two harvests Burnett supervised last fall illustrate this emphasis. In one, from a 600-cord harvest, ash logs made up 35 cords, and also represented 17% of the total value. In another, a 700-cord cut, 70 cords of ash was harvested, representing 19% of the landowner’s return. “Some of these trees we would have taken anyway, but the proportion was larger than it would have been without EAB,” he said.

     Jeffrey Williams, a consulting forester based in Hollis, has many clients in southern Maine, adjacent to the New Hampshire sites where EAB is known to be established. He’s noticed a shift in the advice provided by MFS as the ash borer comes closer. “While we’re still hearing ‘Don’t cut all your ash,’ ” the emphasis is now, “if you have mature trees, you should consider harvesting them.” Williams, a Maine Woodland Owners chapter leader and Board member, said he tells clients, “You probably want to take all the stuff that’s old,” noting that there’s some evidence EAB is attracted to the largest ash trees in an area. Parts of southern Maine have ash still showing crown damage from the 1998 ice storm, and harvesting provides another opportunity for stand improvement, he said.

     Because EAB can travel so quickly and widely, clearcutting ash isn’t recommended anywhere. Burnett said that leaving some ash makes sense to him, since the vectors for its spread are still uncertain. “You may end up with a snag, but we plan for having some of those anyway,” he said.

For Tom Doak, a licensed forester and the executive director of Maine Woodland Owners, EAB has changed the way he considers the value of a particular stand. “Where once we would have favored ash in the residual stand, we now say it may be better to look for oak and maple,” he said. “When you’re choosing between trees, a straight red maple may be a better bet than ash.” Harvesting mature ash trees relatively soon may have another advantage, he said. “By the time EAB is killing trees, there will be quarantines, and that may depress prices.”

     The foresters are agreed that mature ash trees should come out, though it’s still probably not advisable to accelerate planned harvesting for this reason alone. “Ash isn’t really a dominant species in Maine,” Burnett said. “It’s present throughout the state, but usually not in any great concentration.”

     The subject of whether white ash was ever planted as a shade tree, as were sugar maple, oaks, and the now largely vanished American elm, is probably impossible to answer, but Burnett thinks not. “Ash have done well on rich soil, often old farms, but it seems that they’re mostly volunteers,” not something people wanted along streets and houselots, he said. Ash represent about 10% of current stands statewide.

     The effect of quarantines will surely have a significant effect on markets. At the moment, ash logs are selling well, Williams said, and while not sought-after to the exclusion of other trees, it has a strong and steady market for flooring, hand tools, and other uses. Burnett speculates that existing quarantines in Massachusetts and New Hampshire may be boosting prices for Maine logs, though he said mills usually manage their supply to avoid such price spikes. Much of the sawlog supply is exported to Canada, though a mill in Solon is also a steady customer.

     Once counties in Maine are quarantined, that will likely change, as mills favor areas where special protocols aren’t needed, Burnett said. Still, the effect is likely to be gradual rather than sudden, and landowners may still have the opportunity to cut ahead of EAB’s spread.

     There are other conditions which may affect the desirability, and feasibility, of harvesting ash. Jeff Williams said that often grows in wet or marginal areas, and there is now uncertainty about how much can be harvested in winter, due to fewer sub-freezing days. More detailed planning, plus the ability to move equipment in and out quickly, will become more important, so landowners may have to consider these factors when planning harvests, he said.

     There’s really no silver lining in the EAB prognosis, the foresters agree, since it affects all ash species in Maine – white, green and brown/black ash. Its vulnerability, Williams said, only underlines the advice most foresters provide whenever a significant harvest is planned. “Diversity of species is probably more important than ever,” he said. “A healthy forest is a diverse forest, and it’s a buffer against diseases and insects, whether it’s EAB, wooly adelgid, or whatever may come along next.”

Forest ThreatsStaff