First Adelgid Sighting

Marcia reports that she found the first sign of hemlock woolly adelgids in Plummer’s Hollow a couple days ago: remanants of the woolly masses on the undersides of a few twigs on a hemlock tree along the Ten Springs Extension Trail above the Big Pulloff — i.e., less than a half-mile from the bottom. This is what we’ve been dreading for some time now, as we’ve watched the adelgid wave move toward us from the southeast, where some of the best-known old-growth remnant stands, such as The Hemlocks Natural Area and Sweetroot Natural Area, have been destroyed. Adelgids have already established themselves north of us in the Rothrock State Forest, so we knew it was only a matter of time.

Though doubtless the northeast-facing slopes of Plummer’s Hollow were covered with old-growth hemlock two hundred years ago, now only a remnant population of second- or third-growth trees numbering in the low hundreds hangs on in the deepest parts of the hollow. This may be to our advantage, though, in slowing the advance of the adelgids — some reports indicate that hemlocks in rich, mixed conifer-deciduous forests hold out longer than those in pure stands. We are, of course, hoping against hope that a biological control will take hold. Insecticides aren’t effective against the adelgid, and in any case we wouldn’t allow their use even if they did work — overall biodiversity has to take precedence.

We’re in the middle of a cold snap right now, with nighttime temperatures hovering just above zero F, and needless to say we are cheering the cold on. We’d welcome temperatures ten or even twenty degrees colder than that, despite the inconveniences that might cause us. The loss of all mature hemlocks in Pennsylvania, while not catastrophic for the species as a whole, could have a devastating effect on forest ecostystems, especially cold-water fisheries.



About Dave Bonta

I'm the author of several books of poetry, including Ice Mountain: An Elegy, Breakdown: Banjo Poems, and Odes to Tools, but my real work is at my long-running literary blog Via Negativa, where I'm currently creating erasure poems from every entry of the Diary of Samuel Pepys. I'm also the editor and publisher of Moving Poems, a blog showcasing the best poetry videos on the web.

Posted on February 4, 2007, in adelgid, forest health, insects, trees. Bookmark the permalink. 2 Comments.

  1. BoF has used Merit (imidacloprid) soil injections beneath hemlocks in Rothrock SF, treating hundreds of trees with this insecticide which is taken up by the roots and spread throughout the hemlock. It’s lethal to the adelgid for up to 4-5 years. Fort Roberdeau County Park in Sinking Valley has only 4 hemlocks and may treat them with this chemical this spring.

  1. Pingback: Via Negativa » Blog Archive » Only half-here

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s