Strips of Green in the White Mountains
Memorial Day Weekend is late for trees to unfurl tiny, tender pale green leaves. Yet trees growing at the highest altitudes of our State's White Mountain National Forest are among the last to leaf-out each spring.
Hikers are familiar with a curious phenomenon only conspicuous in late spring and again during autumn foliage season: faint diagonal stripes - like a barber pole - appear on forested flanks of many White Mountain peaks.
The stripes are an enduring legacy of early, rough logging in the 70 square mile Pemigewassett Wilderness at the heart of the national forest. In just 15 years at the turn of the last century, the J.E. Henry and Sons Logging empire clear-cut the entire 45,000 acre headwaters from Zealand Notch in the north to the village of Lincoln in the south.
Logging crews carved steep diagonal "dugway" roads to skid spruce logs using a "cut and fill" technique - like a "checkmark" seen in cross-section. Skid trails included "bunter posts" as guard rails to keep hitches of spruce logs on the snow-clad trails.
As the forest grew back, tiny wind-blown birch seeds found skid trails scraped clean of leaf litter and humus an ideal bare soil seed bed. Slopes between the roads covered in thick layers of logging slash eventually reverted to mix of conifers - balsam fir and red spruce.
Each May, pale green stripes appear at bud burst. The faint lines of paper and yellow birch reveal locations of former skid-trails. In autumn, yellow birch leaves contrast sharply with a darker surrounding matrix of conifers on the uppermost slopes.