==============================================================================
TOPIC: Sylvania Wilderness and Uhrenholdt forest
http://groups.google.com/group/entstrees/browse_thread/thread/cced4563b7460079?hl=en
==============================================================================

== 1 of 1 ==
Date: Fri, Jul 25 2008 3:06 pm
From: Lee Frelich


ENTS:

Bob Leverett and his wife Monica drove through Minnesota, Wisconsin and
Michigan Tuesday and Wednesday this week, on their way back the MA.

I met Bob and Monica at Hayward, WI (site of the international loggers
championship) Wed morning, and we visited the Urhenholdt Memorial white
pine Forest in the nearby small town of Seeley. The Uhrenholdt family was
from Denmark, and refused to log their white pine during the logging era of
the early 1900s. Elizabeth Uhrenholdt was Sigurd Olson's wife, and you see
many references to Seeley Wisconsin in his books. The forest (about 40
acres) is divided into two sections, and one has had experimental
treatments designed to regenerate the white pine (i.e. slight thinning of
the canopy and removal of understory red maple). The last treatment failed
miserably, and it remains to be seen whether a recent red maple removal
this spring will be successful. There is a huge cone crop on the pines this
year, so maybe there will be white pine seedlings germinating next year.
The second section has been left completely natural and has an understory
jungle of red maple that prevents the measurement of tree heights. Bob will
report tree heights when he returns home (I think the 160 year old pines
had an approximate maximum of 115-120 feet).

Later that day Bob, Monica and I met my graduate student and his field
assistant at Sylvania Wilderness in Upper Michigan. Sylvania has 15,000
acres of hemlock and sugar maple forest that has never been logged. The
tropical dewpoints and heavy bug attacks that characterize the Midwest in
summer were suspended for the day, presumably due to Bob's presence (the
bugs and humidty returned Thursday as Bob and Monica continued east to
Michigan). We hiked the east shore of crystal clear Clark's Lake through
multi-aged hemlock up to 400+ years old, as well as some very large white
pine about 200 years old, which Bob measured and recorded in his notebook.
The lakeshore has complicated disturbance history with small fires a few
acres in size, due to the dryness of a convex lakeshore and lightning
strikes on tall white pines. The interior of the forest dos not burn and
has more maple and basswood, and windstorms occasionally topple trees, also
creating a multi-aged forest. The interior also has numerous small bogs and
swales, which contain sediment that records the history of nearby stands of
trees over the last 10,000 years. For example, Lee's hollow had black
spruce needles at the base of the sediment (9700 years ago). The spruce
lasted for several centuries, was then replaced by jack pine which lasted
for 3,000 years, then white pine and oak for about 3000 years, and finally
hemlock arrived 3100 years ago, which along with the cooling climate,
reduced fire frequency and allowed sugar maple to largely replace the oak.
Some stands have not had a stand leveling disturbance for the last 2000
years, so there are a lot of very old multi-aged hemlock and maple stands
there today. Our large research plots (total 69 acres where all trees were
mapped) still do not have earthworm invasions, so they can still show what
forests looked like before this invasion started to cause large ecosystem
level changes.

Lee