So, I’m driving into work on Christmas Eve morning, not marveling at how light the traffic is on Route 2 in Carthage, Dixfield, Mexico and Rumford. Or keeping an eye peeled skyward for a glimpse of reindeer pulling a sleigh.

No, I’m scanning roadside woods at 45 mph, looking for signs of beech bark disease so I can stop and photograph it. Signs such as rough bark pockmarked with small cankers. But all I see are young, healthy-looking beech with smooth, silvery bark; dead leaves still clinging to branches.

Figures. When you want to find something, you can’t. But when I was maintaining sections of the Appalachian Trail in Maine in Oxford, Somerset and Piscataquis counties, diseased beech and yellow birch were forever falling across the trail.

Usually it was single trees snapping off about six or seven feet off the ground, or large old trees, and then there were the nightmarish tangled clusters, sometimes joined by softwoods for several hundred feet through mixed hardwood stands.

And I didn’t really know why. I just knew I had to don my Kevlar equipment, helmet and safety visor and get to work with my chain saw to reopen the trail.

I figured it was damage from the Ice Storm of ’98. But had I talked with a forest ranger or forester, I could have learned that beech are being killed off by Nectria coccinea var. faginata. It’s a fungi that invades after the bark is attacked and changed by beech scale insects, Cryptococcus fagisuga. The one-two killer punch has been recorded in Maine since 1932, but it’s worsening.

Anything with a Cryptococcus name can’t be good for trees.

On some of my trail sections, it was so bad that I’d forgo the walk-through inspection sans gear every spring and just hike in after snowmelt, wearing my safety gear and lugging the saw, and enough fuel and oil for about 12 hours of work.

Sometimes it would take a few days of work to clear the path, and I often wondered what the heck was happening.

Well, now I know, thanks to a Forests for Maine’s Future newsletter I received on Wednesday by email and an article within from the University of Maine at Orono.

According to UMaine researcher William Livingston of the School of Forest Resources, warmer winter temperatures from 1999 to 2002 allowed populations of the invasive, bark-feeding scale insect to explode.

This resulted in beech trunks turning white with millions of scale insects. Insect feeding and severe drought at the time weakened the trees’ resistance to fungal infections, and many trees died.

In 2003, beech tree mortality rates in northern Somerset, Penobscot and Piscataquis counties increased sharply, the article states. Both diseased and healthy trees that lived for decades began to die.

After 2002, subzero winter temperatures returned along with normal summer rains and scale insect populations vanished, the article stated.

Livingston and former UMaine graduate student Matthew Kasson did a study, taking hundreds of core samples of affected trees and comparing growth patterns to meteorological records.

What they learned is that warmer winters are bad news for beech trees.

They found a heightened incidence and severity of beech bark mortality and widespread presence of the fungus Neonectria.

“Even though (beech bark disease) has been in Maine for decades, combinations of warmer winters and droughts are associated with unprecedented levels of beech tree mortality,” said the pair, who published their findings in the journal Forest Pathology.

Their findings are worrisome, although I gave up my Appalachian Trail sections due to diabetes a few years ago and no longer deal with the results myself. 

Still, where last winter began warm as is this winter, it doesn’t bode well for beech or for our wildlife that depend on beechnuts for survival, like black bears in the northern forest.

tkarkos@sunjournal.com