“A thing is right when it tends to preserve the integrity, stability, and beauty of the biotic community. It is wrong when it tends otherwise..” Aldo Leopold in A Sand County Almanac.
In this one simple sentence from his essay, “The Land
Ethic,” noted wildlife biologist Aldo Leopold lays out a rather daunting task
for a land steward. If we are to
evaluate how “right and good” our job performance is as stewards of the biotic
community for which we are responsible, how can we practically judge the
integrity, stability and beauty of that community? Just as Aldo Leopold states at the beginning
of his book of essays Sand County Almanac,
“there are some who can live without wild things and some who cannot, these are
the musings of one who cannot,” this blog will also contain musings—the musings
of Hillsdale College’s “Environmental Stewardship” class on our attempts to do
at least a little “right” by a small portion of the biotic community
of the Slayton Arboretum. A community is
not static, conditions change and it evolves over time, and so will our
knowledge base and efforts evolve as we try things and study and learn from the
results. We look forward to sharing our
journey with you!
To get started, let me introduce you to our community. The environment we are using for this
exercise in stewardship is a hillside located on the grounds of the Slayton Arboretum at Hillsdale College in Hillsdale Michigan. The old adage, “Location, location,
location,” has never been truer than when considering an ecosystem. To know what kind of integrity, stability and
beauty is possible, a steward needs to know something about the abiotic and biotic
conditions of the site. Additionally, --
our work as stewards is influenced by the cultural, intellectual, social and
economic resources of the community.
So
here’s a little background about our land. Globally, we are in the temperate forest biome. That means the four seasons here generally
favor deciduous plants. However, there
are site-specific micro-conditions within the biome that further refine the plant
community found in a particular area. In
our case, this hillside resides within a glacial moraine, containing large
amounts of glacial till, (rocks, gravel and sand), which form the
characteristic “hills and valleys” of Hillsdale County. The Slayton Arboretum was built on the site
of an old gravel pit within this moraine.
What the glaciers left behind combined with the vision of Dr. Barber and
his stonemason brother, provided us with some of the most striking features in the Arboretum,
including lovely stone gazebos fashioned from rocks gathered on-site, and a
natural amphitheater built around the “pit.” Here's a link to more information on the history of the Arboretum. Scroll down to read the "History" section. https://www.hillsdale.edu/about/facilities/slayton-aboretum/
As a result of its
location on the site of this former gravel pit, our forest community has a
fairly steep and jagged topography because its sides were scraped and carted
away as gravel. This presents us with
two stewardship challenges, one is dealing with a soil structure that is
comprised of a great deal of compacted rocks, gravel and sand, along with having
a relatively thin layer of topsoil, since that was also disturbed in the not
too distant past. So our soil is rather
loose, lacking a lot of organic humus to act as “glue” holding it
together. As a result, we don’t expect
that it has a high fertility, although this is an area we intend to investigate
much further. The second problem
topography presents for our community is that our hillside is subject to
erosion due to its slope, and the fact that there is a driveway and dorm at the
top. These are impermeable land cover
surfaces from which water runs off onto the hill. 
These wetlands are
in the headwaters of the St. Joseph River, which flows out of the Arboretum
towards the town of Jonesville, later to join up with another tributary, the
Coldwater River, near Union City Michigan.
This branch of the river eventually joins the main branch of the St. Joe
in the town of Three Rivers Michigan.
Our class visited
another branch of the St. Joseph River in Mongo Indiana to get a feel for how
our hillside forest community was connected to the larger watershed of the St.
Joseph.
Our small challenge of holding down the soil and nutrients on the hillside, and keeping them from washing into the wetlands and constructed waterfall on the Arboretum grounds mirrors the larger challenges land stewards in this region have in protecting the quality of the water that flows through the St. Joseph. Some of the major issues facing the St. Joseph River are the protection of wetlands for their contributions to absorbing and filtering nutrients from the river water and as habitat for many river dwelling species, the prevention of stormwater runoff, and the control of nutrients and other pollutants that might flow from land to water. Not surprisingly, our efforts to protect the wetlands below our forest community and to conserve the soil on the hillside will all contribute to not only the integrity, stability and beauty of our immediate environment, but that of the St Joseph River.
For more information on stewardship of the St. Joseph River, check out the Friends of the St. Joseph Web site: www.fotsjr.org/
Here’s a link to an excellent set of informational maps about various aspects of the St. Joseph River Watershed, including sub-watersheds, towns, land cover, natural areas, impaired areas, historical land use, and much more, www.stjoeriver.net/about.htm.
The natural
community one might expect to find in the area of the Slayton Arboretum would
be that of a mixed hardwood forest. The
mixture of trees typically found in a Michigan forest are a combination of
northern and southern hardwood species.
The northern maples and beeches mix with the southern oaks and
hickories. The sandy gravely soils also
favor some evergreen species that can thrive under slightly drier conditions,
such as white pines and red cedar, while the wetter soils of the hill’s bottom
favor species such as arborvitae, tamarack, cottonwood and red maple. Considering the disturbed history of the
site, and the general agricultural nature of the surrounding area, faster
growing species of trees and shrubs characteristic of an earlier successional stage
forest are also found, such as black walnut, black cherry, tulip poplar and
white ash. However, much of the
arboretum grounds have been landscaped with a great variety of specimen trees,
many of which are exotic or have been bred for artificial qualities not common in
nature, such as weeping and variegated forms. The hillside at the Arboretum faces an additional challenge to its integrity, stability and beauty, that of invasive species. There are several pest plant species found in the arboretum that present challenges to the establishment of a healthy and diverse biota. Among the worst offenders are garlic mustard, buckthorn, barberry and honeysuckle, all of which can alter the soil chemistry and make it difficult for seedlings of native species to establish themselves.
Another troublesome plant in our community is the Norway maple, an aggressive and fast growing tree that ties up almost all of the nutrients in the soil to aid its growth, thereby impeding the growth of any plants underneath it. This is a particular challenge for native understory shrubs, herbs and ground covers.
At the beginning of our hillside
restoration project, our forest vegetation community was comprised predominately of garlic
mustard on the ground, honeysuckle and buckthorn at the shrub layer, and Norway
maple dominating the canopy, along with some planted Concolor fir trees and a
large mulberry and boxelder. The dense
cover of these non-native and invasive species meant there was very little
regeneration or growth of any other species.
The site was a visually impenetrable tangled mess, not particularly
beautiful and with
little of its original integrity intact. This particular hillside is the location of the Arboretum's witch hazel collection, which has been struggling to survive with the competition from the invasive species.
little of its original integrity intact. This particular hillside is the location of the Arboretum's witch hazel collection, which has been struggling to survive with the competition from the invasive species.One of the last challenges facing the biota, is browsing by deer. The city of Hillsdale is surrounded by prime deer habitat, and with no danger of hunters and predators within the city limits, deer venture into the area and take full advantage of the virtual salad bar of plant choices available on which to graze. The result of this situation is that native plants favored by deer face intense stress from deer damage, and non-native species that are unpalatable to deer now have a significant competitive advantage. The competition from non-native plants and stress caused by deer browsing is often too much for native vegetation to bear, and it disappears. With the disappearance of the native plants comes the disappearance of their seeds, which cancels the possibility that their offspring will be part of the future makeup of the forest. Through this cascade of stresses, the integrity and stability of the forest is lost. The Arboretum is fenced to keep out deer, but there have been instances of deer breaching the fence and destroying valuable trees and shrubs.
We now come to the question central to our Environmental Stewardship class; given these challenges, how can we restore some of this hillside’s integrity, stability and beauty??????
