Article #88, October, 2004
By Bill Cook
Oaks have long
been a symbol of strength and represent many of the virtues associated with
trees. Oaks have long been featured in the romance of forests as well as held
in high regard among utilitarian users. The oaks of the Upper Peninsula and
across Michigan now have a questionable future.
Oak wilt is a disease
similar to the fungus that killed millions of majestic American elms in the
1960s and 1970s. Elms still exist in our landscape but not nearly at the level
they once held. Oaks may have a similar fate.
Oaks in the red oak
group have a habit of grafting roots among individuals. Through this network
of common roots the fungus can spread 50 or more feet each year. Trees killed
in one year stand as dispersal towers for fungal spore pads the following year,
allowing the disease to spread overland as well. An oak with the smallest wound
during the growing season is at risk. That's why foresters encourage people
to avoid wounding oaks during this time.
The disease has been
running wild across parts of the southern U.P. for at least a decade. However,
oaks have been dying at rapid rates for other reasons, too. Mature and overmature
trees growing on infertile sands create a fragile health condition even in good
years. With the addition of drought, insect defoliations, and a little bug called
the two-lined chestnut borer; oak stands have been disappearing. It's not always
easy to identify the specific cause of death with so many ongoing events.
Oaks stand among the
few trees this far north that produce "hard mast", or nuts. A large
suite of wildlife species depend upon hard mast to one degree or another. The
other common nut tree is beech. Oddly, this tree is also disappearing from our
forest due to beech bark disease. This disease is a combination of a small insect,
called a scale, and several species of fungus. Concentrations of beech in Luce
County have become severely infested. The long term future looks a bit grim
without the presence of oak and beech. The thought of a similar situation with
maples is almost beyond comprehension, but the risk exists.
of firewood has been a major reason for the spread of tree diseases. Ten years
ago this was much less of an issue. In the next few years, we will likely see
many efforts to heighten awareness of the dangers of spreading forest damaging
insects and diseases through firewood.
Gypsy moth is
another firewood hitch-hiker. The cool, wet spring weather in 2004 saved parts
of our forest from the heavy defoliation predicted by forest health specialists.
The Entomophaga fungus tore through the caterpillar populations, killing many
of the larvae before they chewed through much of our forest. Nevertheless, this
fall's egg mass counts are high. Once again, the stage is set for major gypsy
moth defoliation in 2005.
The latest bug
that can be carried with firewood is the emerald ash borer, a pretty little
green beetle responsible for killing millions of ash in southern Michigan and
adjacent areas in Ontario, Ohio, and Indiana. The prognosis on whether authorities
can contain the spread of this borer is not good.
forests of the Upper Peninsula and the northern Lake States are no longer as
remote as they once were. Threats from invasive species increase all the time
and people are moving around more than ever. Our forests are dotted with second
homes. The best hedge against this assault is education. The more we know about
forests and threats to the forests, the better our behavior and decisions will
become. The forest legacy we leave to the next generation will, in part, depend
upon our willingness to learn and exercise caution.
- 30 -
Bill Cook is an MSU Extension forester providing educational programming for the entire Upper Peninsula. His office is located at the MSU Upper Peninsula Tree Improvement Center near Escanaba. The Center is the headquarters for three MSU Forestry properties in the U.P., with a combined area of about 8,000 acres. He can be reached at firstname.lastname@example.org or 906-786-1575.
by Bill Cook, Forester/Biologist, Michigan State University Extension, 6005
J Road, Escanaba, MI 49829
906-786-1575 (voice), 906-786-9370 (fax), e-mail: email@example.com
of these articles is encouraged. Please notify Bill Cook.
By-line should read "Bill Cook, MSU Extension" Please use the article trailer whenever possible.
Michigan State University is an affirmative action equal opportunity institution. The U.S. Department of Agriculture prohibits discrimination on the basis of race, color, national origin, gender, religion, age, disability, political beliefs, sexual orientation, and marital status or family status. (Not all prohibited bases apply to all programs.)
This website is maintained by Bill Cook, Michigan State University Extension Forest in the Upper Peninsula. Comments, questions, and suggestions are gratefully accepted.
Last update of this page was 22 September, 2005
This site is hosted by School of Forest Resources and Environmental Science at Michigan Technological University.