Old Growth Forest in NH
By Dave Anderson
Something Wild: Old Growth Forests
Air date: June 18, 2010
From the Society for the Protection of New Hampshire Forests, I’m Dave Anderson with Something Wild…
What do people think of when they hear the words "old growth forest?" Usually the mental image includes towering redwoods or giant sequoias.
In NH old growth comprises our oldest living "cohorts" of shade-tolerant hardwoods: long-lived beech, yellow birch, sugar maples and red spruce and hemlock. By definition, old growth is NOT comprised sun-loving pioneer trees: poplar, white birch, white pine and fir which require open clearings to become established.
Old growth forests are more than big trees. You "can't see the (old) forest for the trees" when preoccupied by size. Tree height rather than diameter is often a better indicator of age. The bark of old trees is shaggy and coarse.
Trees of many sizes and ages are present: standing dead snags, a random array of down woody limbs and fallen rotting logs found far from any accessible road that long ago would have facilitated logging or clearing for agriculture. Old growth is hard to reach - that's why it's intact!
Old growth is best identified by absence rather than presence of features. What is missing is any evidence of human history: stonewalls, barbed wire, pastures and cut stumps from logging. Evidence of natural disturbances is confined to small gaps in the canopy from the death and fall of individual trees which remain present as downed, rotting logs.
How much old growth is left? According to the last statewide forest inventory in 1997, less than one tenth of one percent of the State’s forest area is documented as old growth.
Old growth is rare because disturbance is common: agriculture, logging, wind, fires, ice storms, hurricanes and even tornados occasionally level our State’s standing timber.
It’s not easy being green!
Something Wild is a joint production of the Society for the Protection of New Hampshire Forests, New Hampshire Audubon, and NHPR. For Something Wild, I’m Dave Anderson.