Sustainability & Soil Health

Although “sustainability” has been used to the point that it may have lost some meaning, it is useful to think of sustainability as those practices that lead to healthy soils. In the broadest sense, soil health, can be defined as “the capacity of a living soil to function, within natural or managed ecosystem boundaries, to sustain plant and animal productivity, maintain or enhance water and air quality, and promote plant and animal health” (Doran, J. Soil health and global sustainability: Translating science into practice. Agric., Ecosyst. Environ. 2002, 88, 119–127). In non-agricultural or developed areas, property owners whether public or private have responsibility for how soil is maintained and rely on landscape architects, engineers, planners, landscape contractors, and soil consultants to provide expertise and services. Understanding how various practices contribute to building healthy soils is critical to true sustainable landscape management.

There is ample scientific (and some not-so scientific) information on the components that contribute to soil health as part of a sustainable strategy. In general, soil health consists of measurable physical, chemical, and biological properties. Soil lab reports give us these measurements and highlight key healthy soil indicators such as pH, organic matter content, and soil texture. Soil reports can be used to make immediate adjustments in amending soils often by following lab recommendations. Soil lab reports can be the most efficient way of linking science with practice in implementing a sustainable land management approach.

A considerable volume of literature supports maintaining soil organic matter (SOM) content as central to a sustainable approach in both agriculture and landscaping. Farmers have long known that conserving soil organic matter has many benefits including higher yields, minimized erosion, and enhanced water resource protection. Landscape professionals who use compost regularly have direct experience with compost-amended soil versus unamended soil. Through this experience, they have learned that plants will thrive in compost-amended soil because of improved physical, chemical, and biological properties. Fewer (or no) chemical inputs are necessary and the plants are able to better withstand drought as well as other environmental stresses.

The direct benefits of using organic amendments to maintain soil organic matter as part of a sustainable strategy have been demonstrated in a recent study in Washington State (Brown, et al., Quantifying benefits associated with land application of organic residuals, Environ. Sci. Technol., 2011). The addition of organic amendments (e.g., composts) to soils resulted in significant and measurable increases in soil carbon storage. With increased SOM came substantial increases in total N, available P, and water holding capacity, along with increased yields and water savings.

In so far that soils are vital to food production and global ecosystem functioning, we need to be good stewards of our soil. It is, therefore, important that we have a basic understanding of soil, by utilizing soil science, and that we adopt strategies that are truly sustainable. Using compost to recycle organic matter back into the soil is an example of a sustainable practice that has very significant economic and environmental benefits.

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Library Park – Sustainable Landscaping at Its Best

Sustainability was a key factor in the overall design of Library Park, located in the Allston section of Boston, which is why on-site soils were utilized and soil organic matter content was closely monitored during construction in the fall of 2010. The park was designed by Michael Van Valkenburgh Associates, who utilized soil consulting services of land scientist Tim Craul to ensure that soils were properly mixed and placed.

Designed to be easily and efficiently maintained, the park has had plenty of time to grow in and is now maintained using only organic landscaping practices, inlcuding the use of stormwater retention to help with irrigation and to mitigate the danger of flooding in the neighborhood.

AGRESOIL COMPOST made in Ipswich, MA, was specified to amend on-site soils. Valley Crest Landscaping spread a 2-inch layer of compost and tilled it to a depth of 6 inches in lawn areas. The compost was used at 30 percent by volume to amend backfill for tree and shrub plantings.  Click here to read more about this sustainable urban project, watch a video, and view photos.

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Elmhurst Park – Brownfield to Greenspace

Once known as the “Elmhurst gas tanks” in Queens, NY, Elmhurst Park is the result of a long process in which the previous land owner cleaned up the property and sold it for $1 to New York City. The park’s creation advances the goals of NYC’s Parks Department’s long-term environmental sustainability plan.

Sustainability features include stormwater collection over approximately half the site in an underground retention system, consisting of perforated pipes and broken stone wrapped in filter fabric to reduce the amount of water flowing into the sewer pipes in the street. Soils used on the project were designed to optimize water holding. Agresource’s Burlington County Compost was chosen as the organic amendment to achieve water holding objectives, while not negatively impacting drainage in lawn areas.

More than 620 trees were planted, were planted, along with shrubs and perennials. Many landscape architects and resident engineers worked on this project including designers Helen Ogrinz and Nancy Prince, with contractor William A. Gross Construction Associates. Click here to read more about this "green oasis."

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The King School Sports Fields – Construction with Sustainability in Mind

King Low Heywood Thomas School, commonly known as the King School, is a private, co-educational day school for Grades PreK-12 in Stamford, Connecticut. When new sports fields were constructed, the school insisted that the root zone meet a very strict standard not only for playability, but to create a field that helps protect the local environment. Protection against compaction by insisting on the right sand and a reasonable soil organic matter content were key components in making a healthy root zone that would require minimal maintenance.

Redniss & Mead Engineers of Stamford hired Pine and Swallow Associates of Groton, MA, to design the root zone and oversee its quality during construction. Agresource made the root zone mix, consisting of 1 part soil and 1 part sand to 1/2 part Agresoil Compost.

Designing the right root zone for playing fields and keeping to the specification throughout the construction process will have a long payback in terms of low maintenance costs for the King School and fit well into its goals of sustainability at the campus.

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Sustainable Food Production in Providence, RI

Compost made at the Rhode Island Resource Recovery Corporation, Johnston, RI, was used to enrich soils in Providence’s southside food growing project prior to planting in the spring of 2011. Agresource’s compost was tilled into existing soils to increase soil organic matter, provide nutrients, and lower soil bulk-density so that new plantings will take root and thrive.

The Southside Community Land Trust provides access to land, education and other resources so people in Greater Providence can grow food in environmentally sustainable ways and create community food systems where locally produced, affordable, and healthy food is available to all. Click here to learn more at the Southside Communtiy Land Trust website.

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Phillips Academy – Creating A Sustainable Campus

As part of its effort to create a more sustainable environment, Phillips Academy, Andover, MA, started a topdressing program for major areas of its campus in the spring of 2011. Their goal is to cut back on the use of chemical inputs and rely on natural systems to keep lawns green and to save money. Both sports fields and campus lawns were included in the new approach.

Prescription Turf Services applied the compost using two different spreaders, a tow-behind (shown in rear) for large open areas and the Ecolawn topdresser (shown in front) for smaller lawn areas.

The combination of aerating and topdressing with AGRESOIL COMPOST constitutes a big step forward in making the transition to sustainable land care. The introduction of compost into the soil profile provides slow-release nutrients, increases soil organic matter, and allows for beneficial microorganisms to thrive and multiply. It also, lowers the bulk density of the soil, helping to relieve compaction in areas that have to endure heavy foot traffic.

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