Homegrown Stewardship Part 1

 
“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.

The following topographic map shows the ridge along the top edge of our hill, which descends to a large area of wetlands at the bottom.  You can locate the ridge on the map where the topographic lines are close together above the red marker, with an elevation of 1100 ft. above sea level.  The wider areas to the east of the marker contain wetlands which can be seen draining into a tributary stream heading northwest of town out of the Arboretum.

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.

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??????

STAY TUNED FOR FURTHER EPISODES!