Archive

forest pests

Several folks have asked me in the past for a comprehensive guide to non-native invasive insects and diseases that affect trees.  Tom D. just sent along this link to a nice report by the National Park Service (NPS).

I took a quick look at it and for my purposes the dichotomous key in the beginning and Appendix C at the end provide a somewhat comprehensive list of forest pests and will be most useful.  Note that some of these pests are native and not considered “important” forest pests.  As with anything dealing with forest stewardship,  it is best to be very cautious about controlling certain pest outbreaks because they form an important part in forest ecology and forest stand dynamics.

However, as we all know, there are emerging threats to our forests that we should take very seriously.  There is a lot in this report about NPS rapid response procedures for these emerging threats that probably isn’t applicable to most of the lands we work on, but don’t forget we have the Central Jersey Invasive Species Strike team that can help fill the rapid response need and provide technical assistance in Central New Jersey.  It is too bad the NJ DEP doesn’t have the resources they should to address these types of emerging problems. And that the Governor eliminated the invasive species council. But that is another story ……

Let me know what you think after you have a read.

Here is the email from the National Park Service:

Damage to forest ecosystems from exotic invasive insect pests and pathogens has been increasing tremendously in the past decades, causing dramatic changes to forest ecosystems throughout the eastern United States.
Responding to requests from National Park Service (NPS) staff in the field for guidance on specific steps to manage a wide range of forest pests, the document, Rapid Response to Insect, Disease & Abiotic Impacts: Procedures to Protect Forest Integrity in Units of the National Park System within Eastern Forest, has been completed by staff from the Northeast, National Capital, Midwest and Southeast Regional Offices of the National Park Service. This is an electronic document, initially drafted by natural resource specialists in the Northeast Region. The document has been broadened to address concerns of all eastern regions, and is signed by the four Regional Directors of the eastern Regions of the National Park Service. The most recent revisions clarified the NPS guidelines to protect cultural resources, in addition to natural resources, when implementing the recommended procedures.

Although this is a document written by NPS natural resource specialists for NPS use, it can also be useful to state and local resource management agencies, contractors, and the general public. NPS has posted the document on the following public internet site:
http://www.nps.gov/nero/ipm/Forest-Insect-n-Disease-Rapid-Response-Plan_final-2010-08-05.pdf

Sometimes the best thing you see all day is a fresh-killed deer with its ass ripped out by vultures.

Today was one of those days, not helped by the bafflingly steamy December weather.

I had the day off, so I took a walk down to Cattail Brook, a preserve near my house.

The first thing that struck me was that a great big tuliptree branch had clobbered our exclosure fence. The metal u-posts were bent like coat hangers.

There was fresh deer scat inside the exclosure.

I walked among the old trees down at the brook – hop hornbeams, lindens, tupelos with their alligator skin bark.

They were framed against the silvery moon-colored bark of beech trees, the “dominant” species by far in this slice of old forest.

Today that luminous beech-glow was more of a haunting pall than the reassuring presence I’m used to.

One by one, the beeches of Cattail Brook are succumbing to beech blight. Also called beech bark scale disease, Nectria, beech canker – the result is generally the same.

Beech Canker

Beech Canker

Sores ooze on the tree, and the smooth bark crackles along hidden fault lines, peeling and erupting. The tree has been colonized by an alien fungus, Nectria coccinea, introduced to it by an alien scale insect, Cryptococcus fagisuga.

An infected beech typically snaps after several years of inner decay, first sending up a dense thicket of sucker sprouts.

I’ve seen the decimation caused by Nectria north of here, in the Catskills and Maine, where the disease has greatly diminished beech forest communities. The old snapped trunks stand sentinel over gangly mishappen suckers – ghosts in the forest.

Nectria has been reported in the southern Appalachians as well, spreading through the Smoky Mountains National Park. I haven’t found any sources noting its presence for New Jersey. Presumably that means we’re in what’s termed the “killing front”, as opposed to the “aftermath zone”.

(A bit of consolation: a small percentage of beeches are showing resistance to the disease complex)

—–

I’m deeply upset by tree blights, and uncertain what can be done. I think they’re a grim reality we in stewardship need to speak more frequently about. They have had and will continue to have immense effects on the ecosystems we care for, effects at least as catastrophic as the presence of Japanese barberry or multiflora rose in the landscape.

Fewer and fewer of our native tree species seem to be free of some introduced plague. The loss of the American Chestnut is only the most stark and well-known of them.

Here are some others that come to mind:

Elms (dutch elm disease)
White Pine (pine rust)
Flowering Dogwood (anthracnose)
Hemlock (Hemlock woolly adelgid)
Balsam & Frazer Fir (Balsam woolly adelgid)
Viburnums (introduced beetles are devastating arrowwood up north)
Oaks (a whole host of blights, most notably gypsy moth)
Ash (emerald ash borer)

Some of these are new and on their way. They are likely to have profound effects on the ecosystems we steward. Frequently, they seem beyond our power to do anything about. At the very least, we need to factor them into our long-term thinking and planning. Maybe we can try to engage in early detection/rapid response to tree blights – if there are any solutions out there.

——

I kept walking down Cattail. I found a second newly dead deer (same blood-and-bones hindquarters). I also found the object of my walk: a little seedling, with gentle evergreen needles, peeking up from the parchment-colored leaf litter at the brook’s edge. A baby hemlock – the only one I know of in the Sourlands. I carefully lifted the chicken wire hoop I had been carrying, drove a bamboo stake into the ground, and lashed the homemade deer guard to it. This one will not become another ghost in the forest.

beech blight links:
http://www.main.nc.us/SERAMBO/BControl/beechbark.html
http://www.dnr.state.oh.us/tabid/5218/default.aspx

Follow

Get every new post delivered to your Inbox.