Tuesday, June 9, 2009

A Grief Observed: The Year the Hemlocks Died (Part 2 of 2)

Our walk to see the largest Eastern Hemlock on the planet had been a pleasant experience – a fairly easy jaunt with an occasional hard, messy stretch to keep things interesting. As we moved toward the gap between Laurel Branch and the Middle Prong of the Little Pigeon River, we reached the big hemlock, the Laurel Branch Leviathan. Tall, wide, and dead. Yes, dead.

We had been warned that this might happen, and we weren’t surprised. An Asian bug – the hemlock adelgid – has been ravaging hemlock forests across the eastern US and has, in fact, infested nearly all the hemlocks in the Smokies.

My friends and I had noticed a significant difference over the past year. In years to come, people will probably speak of 2008-9 as the year when the hemlocks died. Walking in a hemlock forest such as Porters Creek was still a shady, green experience in 2008. Taking the same walk a year later was noticeably different. The sun was now shining where shade had dominated. Looking up through the leafy branches in 2008, one could tell that something was amiss. The branches were beginning to look a bit sparse, but they were still mostly green. By the spring and summer of 2009, those same Hemlock branches were naked and dead, like corpses in a morgue.

The Leviathan had been well-hidden, being discovered only a few years ago by researchers whose passion is searching the Southern Appalachian forests for big trees. But being well-hidden was its death sentence. If the National Park Service had known about this tree sooner, they could perhaps have saved it by dousing it with the chemical spray that kills the adelgids who lodge themselves on the tree’s branches, but the NPS spraying program was too late.

As we walked around the tree, admiring its fading glory, I saw the tell-tale blue and white paint blazes on the tree. I’ve seen these on healthy hemlocks, so I’m pretty sure these marks indicate that these trees had been sprayed, and I’m also pretty sure that the spray usually works… but only if the spraying is started soon enough.
Laurel Branch Leviathan: Going, going, gone...



The NPS has also been experimenting with predator beetles, the sworn enemies of the hemlock adelgid. I’ve read that it costs $2 or $3 to raise a single predator beetle, so this natural, non-chemical approach is slow and expensive. I’m not an entomologist, so I don’t know what I’m talking about, but I’ll say it anyway: the idea of having to spend money to “raise” bugs doesn’t make sense to me. I would have thought that you could throw a male and a female on an infested hemlock, and they’d do what predator beetles do – eat hemlock adelgids and reproduce. Seems free and easy to me. But, like I said, apparently I don’t know what I’m talking about. Maybe the predators get eaten by woodpeckers or killed by heat or drought. Whatever the reasons, it isn’t free and easy, which shouldn’t come as a big surprise, since nothing ever is.

Luckily, the hemlocks probably won’t become extinct because the adelgids seem to prefer older trees. So young hemlocks will continue to sprout, but they’ll die after a few years, only to be replaced by a new generation which will also die young. This may be good news for Yellow Poplars which compete with the Eastern Hemlocks for dominance at elevations below 4,500’. For the overall ecosystem there will undoubtedly be negative consequences, but of course, nature will do what nature does – adjust, adapt, and move on.

It’s ironic that just a few yards away from the Leviathan Hemlock stands a large poplar. In fact, because poplars grow larger than hemlocks, that less-than-record-sized poplar is actually larger than the record-sized hemlock. Talk about stealing a guy’s thunder and kicking him while he’s down…!

My hope is that the predator beetles will eventually become self-supporting and will feed on those nasty, little adelgids with zest and will reproduce with gusto. If that happens, then all those young hemlocks might survive childhood and grow into handsome adults. So there is hope, but probably not in our lifetime.

And so, after a leisurely lunch by those two big trees – one representing the past and the other the future – we continued our walk through the gap and on to the Middle Prong. The forest along the Middle Prong is deep, green, and open. Another sylvan cathedral. The ground was covered with mosses, ferns, and spring wildflowers, and most of the trees were hardwoods, not hemlocks. This untarnished piece of creation will probably survive and flourish, unaware that a plague is sweeping through the hemlocks nearby.

The surrounding forest is open and green.

With a little luck we’ll not destroy this forest by some act of greed or stupidity; although, the list of victims – chestnut, elm, fir, hemlock – continues to grow. Thankfully, Nature doesn’t grieve as we do. It simply notices that the fir or hemlocks are gone and goes about its business of filling in the gaps. Adjust, adapt, and move on. And, thankfully again, given an adequate amount of soil and water, it does its job with power and extravagance. Yes, I’ll grieve for the loss of the Eastern Hemlocks, and yet I’m confident that whatever Nature decides to do in the Smokies, it will be beautiful.

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