Michigan: Hunter explains kinds of trees deers need, especially hemlocks in winter

Ask most deer hunters about what sorts of forests and woodlots are
best for white-tailed deer and many immediately will zoom in on those
that produce food: oaks and other mast-producing trees. Others, with a
little better understanding of the creature’s year-round needs, will
talk about early successional forests — aspen and the associated
understory, where forbs and shrubs provide browse when mast isn’t
available. But only a few understand the importance of conifers to
deer. In short, northern Michigan whitetails would struggle mightily
without the hemlock, cedar and other conifers that help get them
through the winter. “Stands of hemlock and northern white cedar
intercept snow and make travel by deer much easier,” said Craig
Albright, Department of Natural Resources wildlife biologist at
Escanaba.

“Though the harvested tops of timber species, such as sugar
maple, red maple and aspen, are important food sources, the food and
cover must be in close proximity.” Albright explains it another way:
If the tops of harvested timber are the “kitchens” for wintering
whitetails, the conifer stands are the “bedrooms.” “These complexes
house deer for up to four months each year,” Albright continued. “A
productive wintering complex must have a balance of food and cover in
a mosaic of different forest types. Removal or imbalance of either of
these two components leads to reduced capability of the wintering
complex to support deer.” Western Upper Peninsula Wildlife Supervisor
Bob Doepker agrees.

“The absence of logging leads to decreased amounts
of food available from harvested tops and also a reduction in the
regeneration that deer will be able to feed upon in future winters,”
Doepker said. “However, the indiscriminate harvest of conifer cover
leads to a loss of shelter and the decreased ability of deer to
conserve energy, a loss they can ill afford during stressful winters.”
Annual snow depths are relatively low in the south-central Upper
Peninsula, so deer in that area are more loosely associated with
conifer cover than those that “yard up” near the Lake Superior
shoreline. Cedar is the predominant cover in the central and eastern
U.P., but deer are strongly associated with Eastern hemlock in the
northwestern U.P. Hemlock is a slow-growing species that may take 200
to 300 years to reach maturity and can live to be 400 years old.
Unfortunately, the cumulative loss of hemlock across the U.P.
landscape is approximately 80 percent since pre-settlement times.

Terry McFadden, a DNR wildlife biologist in Marquette, is particularly
concerned about the loss of wintering habitat along the Lake Superior
shoreline in northern Marquette County. “Stands of hemlock are perhaps
the most valuable of all conifers in terms of providing shelter from
snow, wind and cold temperatures,” McFadden said. “The very small and
dense needles intercept snow and serve as a sort of roof that creates
a microclimate of warmer temperatures below the forest canopy. This
protection also allows deer to move more freely, while expending less
energy, as they travel to and from local food sources within wintering
complexes.” The loss of conifer cover in deer wintering complexes is a
major concern to Kevin Swanson, the biologist responsible for the
DNR’s Landowner Incentive Program in the U.P., who concentrates much
of his efforts on reestablishing mesic conifer habitat on private
land. “In the mixed hardwood-hemlock stands located within yarding
complexes in the northern portions of Marquette and Baraga counties,
traditional management involves harvesting a portion of the hemlock
during each 15-year rotation,” Swanson said. “But, because sugar maple
is more aggressive in becoming established after a harvest, each
subsequent harvest rotation leads to a more pronounced loss of
hemlock, further deteriorating the area’s ability to sustain deer
through the winter.” Hemlock does not regenerate as easily as sugar
maple or aspen. Many of the hemlock stands that exist today were
established after large-scale natural disturbances including wind
events and forest fires.
http://www.pressandguide.com/stories/012809/spo_20090128014.shtml

To keep this blog going it has to keep growing!

What’s most essential is you click below to: comment, email, repost,
share this…

Leave a comment

Your comment