With President Mary Sue Coleman's announcement in September of a series of campus sustainability operational goals -- including a 40 percent reduction in chemical usage on campus by 2025 -- Plant Buildings and Grounds Services is turning to more sustainable landscape maintenance practices.
Sustainable landscape management encourages the use of the systems created by nature: healthy soils supporting healthy plants. The foundation of an organic program requires that the plants and soils be viewed as extensions of one another, existing in a perfect symbiotic relationship. This “bottom up” focus contrasts with the conventional maintenance mindset of treating specific plant health conditions from the “top down” through the application of synthetic chemicals.
Organic soils management restores and maintains the natural nutrient cycling system and is at the heart of any organic landscape program. The benefits of this natural approach include improved nutrient and moisture availability and retention, disease suppression, aeration, and degradation of harmful pollutants.
Micro-organisms feed on bacteria and fungi, excreting nitrogen in a form that is easily absorbed by plants. The symbiotic relationship between fungi and roots helps plants filter needed micronutrients from the soil. An organic program focuses on building up the components needed to optimize nitrogen and nutrient cycling.
One of the first steps toward implementing these management practices is to conduct some tests using Compost Tea. Compost is the aerobically decomposed remnants of plants created through the management of heat, moisture, and aeration. The result is a nutrient rich environment for beneficial bacteria, fungi, and protozoa that can be applied directly to the soils. These microorganisms control pests (pathogenic organisms) and aerate the soil, providing the opportunity for extended root development. All herbaceous and woody materials from campus along with additional components are collected for composting, and four burlap sacks each are filled with 20 pounds of compost creating a system that is similar to how drinking tea is made. The brew consists of water, fish emulsion, seaweed extract and molasses. Air is pumped into the bottom of the tank for 18 hours to create a healthy, oxygen rich environment in which the microorganisms thrive. Once completed, the brew is applied directly to the lawns.
Utilizing the campus lawns as a living laboratory, the Compost Tea Pilot Program will compare the effects of a Compost Tea Five sites across campus are being monitored for above and below ground response to the treatments, with staff measuring both soil and vegetation responses to provide information relevant to ecosystem function and for any implications to landscape management. The pilot project will test a sustainable soil management hypothesis which asserts that the use of Compost Tea will increase organic matter and microbial activity in the soil, thereby reducing the need for synthetic fertilizers. Adding organic matter serves to improve soil structure, which will facilitate infiltration, aeration, and improve water-holding capacity. Together these traits increase the ability of the soil to retain nutrients and support soil microbial activity. This hypothesis will be tested through a comparison of current turf maintenance practices with those of the sustainable management program. These parameters will be measured through soil testing, with comparisons made between soils receiving current treatment and soils receiving a compost tea amendment.
The objectives of the project are two-fold:
- Develop a pilot project testing sustainable landscape management practices on campus, and;
- Assess the above and below ground responses to the use of compost tea versus synthetic fertilizer.
Each site will receive the following treatments; a section of lawn will receive the standard synthetic slow release granular fertilizer, another section will receive compost tea applications and another section will not receive anything. Compost tea applications will be made monthly from May thru October, granular fertilizer applications will be made in May, September and November as per the standard Grounds work plan.