Friday, March 21, 2014

Are Deer Changing the Look of US Forests?

Interesting reading......I was sent the below news release by a botanist from the US Forest Service out of the Durham, NH, Northeastern Area State & Private Forestry office.  This news release is the result of two recently published studies, one from Cornell University researchers entitled "Deer Browsing Delays Succession by Altering Aboveground Vegetation and Belowground Seed Banks" and another from University of Pittsburgh researchers entitled "In a long-term experimental demography study, excluding ungulates reversed invader's explosive population growth rate and restored natives." I wanted to share this information with my readers.  Much of what these scientists are documenting, with rigorous scientific research, reinforces what I have been seeing in the field.  Is deer impact reduction the only way to address invasive plants at a landscape scale, while also allowing forests to once again grow new trees?  Good question, read on....

Overgrazing by deer is changing the face of U.S. forests
by: EarthSky March 18, 2014

Scientists in the U.S. Northeast published two studies examining the impact of deer overpopulation on natural ecosystems in early March 2014. Biologists at Cornell University investigated disruptions by large numbers of deer to natural growth in developing forests. University of Pittsburgh researchers showed how large deer populations are causing an increase in garlic mustard, an exotic invasive plant, in forest understory fauna. In both instances, the root problem is overgrazing of native plants by deer that open up more growing space for invasive exotic plants that deer find unpalatable.

These studies were conducted in Ithaca, New York and Pittsburgh, Pennsylvania. But the problem of deer proliferation is widespread across the U.S. and Canada. Their numbers have increased dramatically for several reasons. Since the arrival of European settlers more than 300 years ago, the deers’ natural predators, wolves, have been exterminated. And, as human populations have increased, deer forest habitat has shrunk drastically, mostly giving way to suburban lawns, gardens and farms that can also provide a deer’s food sources. Compared to historical population estimates prior to European settlement, deer populations today have increased, depending on location, by four to 10 times.  Click here to read the rest of the news release.

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