Sunday, September 16, 2018

Tree Mortality 2018

Sections of Southern New England are experiencing severe tree mortality this year.

Massachusetts has estimated 2.5% of the 80,000 acres surrounding the Quabbin and Wachusett reservoirs has been severely impacted. I suspect that figure is reasonable estimate overall for a roughly diagonal swath from the Quabbin area through Eastern Connecticut down to the Rhode Island shore.

[Gypsy moths were] first detected in Connecticut in Stonington in 1905 and had spread to all 169 towns by 1952. In 1981, 1.5 million acres were defoliated in Connecticut. During an outbreak in 1989, CAES scientists discovered that the entomopathogenic fungus Entomophaga maimaiga was killing the caterpillars. Since then, the fungus has been the most important agent suppressing gypsy moth activity

1971 was also reportedly a bad year.

But what we are seeing this year is simply unprecedented.

Some other links:

We had the driest weather since at 2003 during 2015 and 2016 (I know this just from my electric bill noticeably declining from reduced sump pump usage!). The beginning of Spring 2017 was also dry. This meant the fungus didn't have proper conditions to spread. On my property I noticed late in 2015 visible gypsy moth egg masses perhaps for the first time in my life since the early 80s. 2016 had extensive defoliation on some trees, and lots of egg masses. 2017 was extensive defoliation but late in June the fungus kicked in killed the caterpillars in the nick of time before they would have pupated. Didn't even see a caterpillar this year, although 20 miles away where I work there was moderate but not total defoliation.

This spring I noticed pockets around here where the trees did not leaf out.

I emailed the CAES forester who said they belief was it was a combination of the Two-Lined Chestnut Borer and an associated Armillaria root rot (although it is not clear to me from the reading I've done if the root rot follows the borers, or the borers like trees stressed by the root rot).

6/17/2018 -- North side of Route 14A at the Plainfield/Sterling town line:

6/17/2018 -- Old Mill Rd., Charlestown, R.I. -- vicinity of the Narragansett Indian Health Center.

As I drove around this morning, in RI I started noticing some severely defoliated patches, especially with oaks growing on ground that was rocky and dry. Usually in conjunction with mountain laurel.


Following are in Canterbury, Conn.:

Depot Road just south of Shagbark Lane

Gooseneck Hill Road:

Gooseneck Hill & Lisbon Road(?):

Not sure:

Bingham Road:

South end of Kitt Road -- there is a particularly bad band of damage that runs roughly along the ridge dividing the Quinebaug and Little River Valleys.

Canterbury Elementary School, Kitt Road:

Kitt Road:

West end of Buck Hill Road, looking east:

End of Tripp Hollow Road, Canterbury...I grew up the other side of what is a field now being constructed. I believe this was prompted by solar farms being built on farmlands, pressing farmers to clear their woods to replace fields they formerly leased.

Looking west from Tripp Hollow to the ridge between North Society Road and Brooklyn Road:

These next two I can't positively remember where I took them; they were in the Canterbury/Hampton/Brooklyn area.

Drain Street, Hampton, Conn. south of Bigelow Road looking south.

West side of Stetson Road, Brooklyn, Conn. north of the power lines:

North side of Route 6, Brooklyn, Conn. west of Stetson Road.

Coventry, R.I.:

Pitch Pine & Scrub Oak area hit hard; Nicholas Road.

Not sure where, Coventry/West Greenwich R.I. area:

Plain Road, West Greenwich, R.I.

Severly underexposed photo -- but an important point. Newport Road on the Sterling, Conn./Coventry(?) R.I. border. I believe this is called a "Modified Clear Cut" where they leave a few trees per acre. I've seen several of these that have, however, had most if not all the mature trees within the clearing killed. I presume without other trees around them they received an unusually high pressure per tree from the Gypsy Moths.

Route 14A at New Road, Plainfield, Conn. looking west.

I am pretty sure the yellow trees are Ash trees starting to turn their autumn colors. So these photos have:
1) Gypsy Moth killed trees (gray);
2) Two-Lined Chestnut Borer killed trees (brown);
3) Ash trees, which will all likely be dead in about 10 years from the Emerald Ash Borer infestation, the leading edge of which was first detected in the area two years ago.

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