Amended attitude: a new commitment to soil health using compost
By Gary Gittere
Over the past several decades, sports turf managers, farmers, and homeowners have embraced modern science by using synthetic chemicals to reduce turf diseases, increase crop yields and make lawns green. The use of synthetic inputs has indeed shown immediate and impressive results; yet are the long-term effects as beneficial as they seem?
When a soil analysis is taken, the focus is primarily on what the turf or plant needs related to nutrients, pH, etc. A renewed perspective of analyzing soils is emerging; instead of looking at turf needs from the top down, the new shift is looking at the soil, from the bottom up. This shift is showing us that using inputs in the quantities prescribed may not be necessary resulting in a two-fold benefit: reducing the impact on the environment and saving money.
By analyzing the chemical, physical, and biological properties of a given soil, we can determine what it actually needs—without the guesswork—which is more beneficial to the performance of the vegetation.
Novel tools and techniques are currently being used to help detect microbial populations in diseased and healthy soils. As the Soil Science Society of America states: “Soil provides ecosystem services critical for life: soil acts as a water filter and a growing medium; provides habitat for billions of organisms, contributing to biodiversity; and supplies most of the antibiotics used to fight diseases.”
You may not realize that there are more living organisms in a teaspoon of healthy soil than there are people on the earth. So why is this important to anyone managing turfgrass, plants or crops? Soil organic matter, the lifeblood of a healthy soil environment.
Organic matter includes any plant or animal material that returns to the soil and goes through the decomposition process. Plants obtain nutrients from two natural sources: organic matter and minerals. In addition to providing nutrients and habitat to organisms living in the soil, organic matter also binds soil particles into aggregates and improves the water holding capacity of soil. The US Composting Council’s Strive for 5% program states: use of STA certified compost will help you confidently achieve 5% organic matter efficiently and cost effectively by using compost, produced from locally recycled organic residuals.
Most of our soils today are depleted of valuable organic matter creating challenging environments for the proliferation of plants and turfgrass. Improving the health of our soils by increasing soil organic matter results in billions of microorganisms that help to fight soil borne diseases, improve water-holding capacity, and more efficiently use organic and non-organic nutrients. Organic matter positively influences, or modifies the effect of, all three soil properties.
When soil organic matter is minimal, it becomes increasingly difficult to establish and grow turf and plants due to issues with fertility, water retention, compaction, erosion, and diseases. A common challenge heard in the sports turf world is the impact of heavy play on sports fields. This creates a major challenge when attempting to improve vegetative cover on these fields. As down time is normally limited, how can the turf establish itself before play resumes? More positive results are likely when the soil is evaluated and the proper level of organic matter established. A healthy and sustainable soil environment will help foster the establishment of the plant roots, lessening the impact of renewed play and reducing the need for continual sprigging, seeding, or sodding.
Increase organic matter economically
How do you economically increase the soil’s organic matter? By using a soil amendment high in organic matter and microbial populations. Compost offers the most practical, economical and sustainable means to rebuild our topsoil layer and handles the most diversified amount of organic waste compared to other methods. Using 1-2 inches of compost when renovating or ¼-½ inch of compost to topdress a sports field or fairway will increase the soil’s organic content, adding beneficial microbes to help fight soil borne diseases.
Past and current studies conducted by Cornell, Penn State, Ohio State and others, outline the many benefits of using a soil amendment such as compost on sports fields to create healthy soils. Amending poor soils with a product high in microorganisms, such as compost, is one of the best things you can do for your soil. As stated by Penn State’s “Using Composts to Improve Turf Performance”: “If you have been searching for ways to improve turf performance in marginal or poor soils, consider using compost as a soil amendment. In clay soils, good quality compost will improve structure, reduce surface crusting and compaction, promote drainage, and provide nutrients. In sandy soils, compost increases water and nutrient retention, supplies nutrients, and increases microbial activity. These improvements promote faster turf establishment, improved turf density and color, increased rooting, and less need for fertilizer and irrigation.”
Controlling turfgrass diseases, a major challenge for all turfgrass managers, incurs significant cost to both budgets and the environment. As regulations on restricting the use of herbicides and pesticides continue to tighten, turfgrass managers are looking at alternative solutions that work within budgets and local regulations. Dr. Eric Nelson from Cornell University states in “Using Biological Control Strategies for Turf”:
“Over the past 10 or 15 years, studies have clearly demonstrated the potential for composts to reduce the severity and incidence of many turfgrass diseases. For example, monthly topdressing applications of composts at rates as low as 10 pounds per 1,000 square feet are effective in suppressing diseases such as dollar spot, brown patch, Pythium root rot, Pythium blight, necrotic ringspot, red thread and Typhula blight.”
The use of compost to amend soils is not new, being mentioned in books as far back as the early 20th century. In the past 40 years, a significant and growing body of research highlights the impacts of compost on a variety of plant diseases. Studies show that compost can help reduce virtually all major soil borne pathogens. With continual focus on reliable studies combined with results from full-scale application in the field, the use of compost may become great enough to be included as an integral element in your pest management program resulting in reduced pesticide applications.
Selecting a compost
When selecting a compost to ensure desired results on sports fields it is essential to locate and use a product of high quality and consistency. Fortunately, the modern composting industry makes this possible. A procedure used by F. Dan Dinelli, CGCS Superintendent, North Shore Country Club Glenview, IL, helps ensure the compost chosen is optimal for his use. It involves a series of tests analyzing the chemical, physical and biological activity of the material. From a chemical perspective, you want to choose compost that has a low C/N ratio (<16:1), a pH in the range of 6.5-8.5, and a compost that is stable and mature. Physical characteristics include moisture levels at 35-45%, a well-screened product, and dark brown or black in color. A great diversity of bacteria, fungi, protozoa, and beneficial nematodes provides the guidelines from the biological perspective.
The microbial populations in compost can be identified and quantified at a very modest cost. Selecting a compost that participates in the US Composting Council’s Seal of Testing Assurance Certification program will ensure the material meets stated parameters and adheres to your desired needs.
Parks and recreation departments are challenged every year with ensuring that their heavily used sports fields are safe for residents to use. Many fields in the eastern US are compacted clay, making turf establishment difficult. Many supervisors add sand to amend the soil, believing it will help improve drainage and create an environment beneficial for growing grass. However, a lot of sand is needed to change a native soil’s profile. And sand combined with clay soil, water and heat produce a compacted “brick” playing surface.
By amending these native clay soils with a premium compost, you will begin to create a healthy planting environment. You will increase organic matter in the soil helping to create a much safer playing surface and quicker establishment of vegetation that will more effectively survive the rigors of heavy play.
Ensuring playing fields are safe by using methods that include compost will help improve turfgrass coverage and reduce soil compaction. Buffering pH levels, improving the soil’s water holding capacity, increasing the cation exchange capacity to reduce and improve synthetic chemical utilization, are just a few of the many benefits of using compost as part of your fertility program.
The use of premium compost for the maintenance or construction of sports fields has become a common practice, changing the perception of age-old practices by turfgrass managers.
Researchers at the University of Florida are conducting studies with compost inoculated with beneficial microbes to determine effects on diseases. Additional studies and research by universities and turfgrass managers will lead to a higher comfort level for utilizing these type of fortified compost products.
I challenge you to Amend Your Attitude and contact your local college or university’s Turfgrass Department, fellow golf superintendents, or turfgrass manager at a nearby Parks & Recreation department to discuss how they are creating healthy soils using compost. You may be surprised at the feedback you receive and hear the excitement in their voices as they impart the impressive results they are obtaining with compost.
Gary Gittere is the sales and marketing manager for McGill Premium Compost and President of the North Carolina Composting Council
Many recent projects have reaped the benefits of using compost and are specified by engineering and landscape architectural firms. An example is the recently constructed training facility for the Washington Redskins in Richmond, VA that used 2 inches of premium Compost amended into the native clay soil, to ensure the Bermuda sod would effectively root. The company maintaining the facility was so impressed with the results that it chose to topdress with the same compost on both the practice fields and surrounding areas in subsequent years, helping to ensure and maintain a healthy soil environment. Similar projects have been specified for sport field renovations in North Carolina, Virginia, West Virginia, and many other states.