Earth's Oldest, Largest Trees Are Disappearing

Right near the edge of the National Radio Quiet Zone in West Virgina's Monongahela National Forest is a 50 acre patch of virgin old-growth forest, roughly the size of 10 Manhatten city blocks. It's an amazing spot--imagine if some much larger, more typical Eastern US forest collapsed on itself into a dense core of mossy deadfall and ancient trees as wide as lighthouses. Even the empty spaces seem to radiate green, and zone contains some of the most satisfying air a human can breathe.

The tiny patch is now known as the Gaudineer Scenic Area, and is surrounded by a recovering clear-cut zone. Beyond more recent preservation efforts, Gaudineer exists for one reason: a measurement error. When land speculators were surveying the area in the mid-1800s, the operation's chief failed to make the neccessary correction for the difference between magnetic north and true north. It left a sliver of land, which was later claimed by a shrewd surveyor who'd noticed the mistake, parceling all of it out for further logging purposes except this small, still-surviving box of forest.

Eventually, after the establishment of Monongahela around the old-growth zone, a Forest Service administrator saw the situation for what it was: this box of land was an important accident. Virgin forests were all going away and taking their old, massive trees with them. Gaudineer got a special protected designation within the forest--as a "scenic area" though there's nothing within 100 miles that isn't scenic--and now it's a popular destination. And that's for a good reason: old, large trees are disappearing and, as described in a paper out tomorrow in Science, it's a worldwide phenomenon with potentionally catastrophic consequences.

You knew, of course, that our oldest and best trees are going away. That's no surprise. But what the paper, authored by David B. Lindenmayer et al, offers isn't a lamentation, but a summation of a global crisis. Old trees aren't just symbols, but the cornerstones of vast ecosystems. When some ancient tree goes down, their younger, smaller replacements can't do nearly the same work.

Large old trees play critical ecological roles. They provide nesting or sheltering cavities for up to 30% of all vertebrate species in some ecosystems . Large old trees also store large quantities of carbon, create distinct microenvironments characterized by high levels of soil nutrients and plant species richness, play crucial roles in local hydrological regimes, and provide abundant food for numerous animals in the form of fruits, flowers, foliage, and nectar. In agricultural landscapes, large old trees can be focal points for vegetation restoration, facilitate ecosystem connectivity by attracting mobile seed dispersers and pollinators, and act as stepping stones for many animals.

That up-for-grabs era of American wildlands in which our lucky surveying error happened is still underway in large parts of the world and even in the US: Yosemite National Park lost a quarter of its old, large tree density between 1930 and the 1990s. And it feels a bit strange to be sending up flares about an ecological crisis that isn't (directly) climate change, but of course the disapperance of places like Gaudineer--oxygen factories that feed on CO2--has everything to do with the shifting makeup of our atmosphere. Old trees breathe deeply.