Arboretum

     With the focus of environmentalism increasingly shifting toward sustainability and the reduction of GHG emissions, the Arboretum is often overlooked during environmental discussions at Carleton.  However, the 880-acre Arboretum (as well the college's maintenance of 33-acre McKnight Prairie remnant) is very arguably the most significant commitment Carleton has made to environmentalism to date.  The Arboretum functions as much more than a natural land preserve and a native species sanctuary.  While schools and institutions increasingly look to carbon offset programs to claim reductions in their GHG emission totals, Careton need look no farther than its backyard.  Although no number has been agreed upon and additional testing will likely be needed to establish an official number, national approximations for land types suggest that Carleton's Arboretum is sequestering about 750 tons of carbon per year.

The Carleton Arboretum website can be viewed here: https://apps.carleton.edu/campus/arb/

Grounds

On-Campus Prairie Plantings

• Stabilize soil (reducing erosion) much more effectively than grass.
• Increase retention of water in the soil, which also decreases contaminated storm-water run-off.
• Provide a sanctuary for native species of plants, animals, insects, fungi, the works.
• Sequester carbon: native plant communities, especially prairie ecosystems, are significantly more effective at storing atmospheric carbon in the soil as compared to bluegrass.
• Promote a new aesthetic and fights the aesthetic vice-grip that homogeneous bluegrass plots has on our culture, particularly bluegrass as a prerequisite for stateliness.

Corn-based Fertilizer

• Corn-based fertilizer is used whenever Grounds projects and maintenance requires fertilizer.
• Corn gluten, a bi-product of corn, is both a source of nitrogen for lawns and acts as an effective weed control product.
• It is a safe product for mature plants, animals and people
• Carleton uses corn gluten produced at an ethanol plant in Claremont, MN
  • Al-Corn Distributor Website: http://www.al-corn.com/.

Vegetated Swales and Runoff Ponds

• 3 locations on campus:
  • West Gym parking lot: handles runoff from West Gym parking lot and Townhouses before it enters the Cannon River.
    
  • North of Facilities parking lot: handles runoff from Facilities parking lot (which drains all the way from in front of Sayles) before it enters Spring Creek.
  • Retention Pond in the Lower Arboretum: handles runoff from the Recreation Center parking lot.
• Wetland species filter out contaminants and nutrients (fertilizers), which can greatly reduce anthropogenic eutrophication.
• Swales increase groundwater retention, thus reducing runoff, which is often contains contaminants.
• The effectiveness of swales as retainers of contaminants can be negated if so much drainage passes through at once (such as during a strong storm) that flooding occurs and no time for filtering is provided.

Native Landscaping 

• In addition to multiple native prairie plantings around campus, Carleton Grounds attempts to use only native plant species in all landscaping projects, even ornamental.

*All text on this page by Chris Erickson ('08-'09 ENTS Intern)