I chose Kettletown because it looked substantial in size and was not too far away. It is only 22 miles from New Haven, but actually there are no major roads in between so it was almost a 40 minute trip by car.
Kettletown State Park Entrance
There was no shortage of eastern hemlocks. Some looked rather infested with hemlock woolly adelgids (Adelges tsugae). These are insects in the family Adelgidae, a group of Hemipterans (True Bugs) that are closely related to aphids. The adelgids feed at the base of hemlock needles causing heavy dessication of the tree. Most hemlocks that you see these days are infected with these critters and it is really a sad site. The white stuff in the picture is the woolly wax that the adults use to protect themselves and their eggs. I read that the invasion of the hemlock woolly adelgid occurred back in the 1920s.
Eastern Hemlock: underside w/ adelgids
One of my favorite things to see in the forest during the winter months are beech trees, who hold on to their leaves through most of the cold season. American beeches are the trees with the nice smooth gray bark that people like to carve their names into. I suppose I like them because they really grab your attention in the winter. A sign of life in an otherwise sea of emptiness.
I did not know that oak trees are in the same family as beeches (Fagaceae). That is probably why oaks tend to hold on to their leaves in winter as well. Some members of the beech family are evergreens. I read that much of the diversity of this group is in Southeast Asia, and dispersed here via land bridges that formed in the Pleistocene.
American Beech (Fagus grandifolia)
Family: Fagaceae (Beeches)
Random Bracket Fungus
3 comments:
nice pictures, even with the cheap camera. Probably, the photographer is good!
Hemlock woolly adelgid was not introduced in the 1920's. That's inaccurate information that has been circulating all over the place. It was described as a new species in 1924 by a guy in California so I think that is where that date comes from - an assumption that the first record in North America corresponds to when it was introduced here. DNA sequences tell us that the adelgids on the east coast that are killing all our trees match insects in Japan and that the west coast insects are well diverged from the east coast ones. Molecular dating says that the western adelgids diverged from the Japanese ones a long time ago (6 million years ago, give or take) and are therefore probably native out west. The first record on the east coast is in Richmond, VA in 1951 so it was introduced to the east coast from Japan some time before that date. See Havill et al. 2006. for the details:
http://dx.doi.org/10.1603/0013-8746%282006%29099%5B0195:MDFHWA%5D2.0.CO;2
Thanks for the info Nathan. I promise I have been listening during your talks - rather than zoning out. I just didn't remember the dates.
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