BioCycle July 2004, Vol. 45, No. 7, p. 52
Country club in Illinois uses blend of yard trimmings and biosolids compost on its golf course finding positive results and improving turf ecology.
Dan Dinelli

THE GOLF COURSE at the North Shore Country Club in Glenview, Illinois benefits greatly from applications of compost. As the superintendent of the country club, I first became interested in applying compost as a soil amendment after reading research indicating its many soil benefits. For example, investigations by such persons as Michael Boehm of Ohio State University and Eric Nelson of Cornell University showed the impact of applying high-quality compost on supplying nutrients, adding a diversity of organisms, plus promoting disease suppression. Yet because compost is not widely used on golf courses, I wanted to participate in further research here at North Shore.
Actually, I can trace my first introduction to compost use back to my grandfather, Frank Dinelli – a former greenskeeper at Northmoor Country Club – who gave me a book called Turf For Golf Courses (published in 1917). It had a chapter devoted to “Manures, Composts and other Humus Materials.” My grandfather definitely made good use of organic materials, including compost and nutrient-rich silt harvested from a nearby river.
Experiments On The 5th Fairway
In 1996, North Shore got its first research opportunity by participating in a two-year study of various composts directed by Michael Cole of the University of Illinois. The study objective was to observe differences in diseases – specifically snow mold depression – between various plots. While none showed a depressive impact, the plots treated with compost had a notably earlier green-up and recovery rate versus the control plots. We then repeated applications late spring of 1997. Observations through the remaining growing season showed strong dollar spot (Sclerotinia homoeocarpa) suppression – up to 80 percent reduction; improved turf color and density, and increased earthworm castings. Thus, while our initial objective of snow mold suppression was not observed, our experiment to test organic products to improve overall turf ecology proved quite successful.
QUALITY COMPOST IS KEY
We have tested many different types of compost on our fairways – including composted steer and poultry manure, sometimes mixed with litter; biosolids; yard trimmings; brewery waste; and earthworm castings. Now we have settled into an affordable blend of 50/50 yard trimmings and biosolids. Typically we blend the two feedstocks, as we load the Satellite Screen making a pile during late fall. Early to mid-summer, when the pile is dry enough to be workable, we turn the pile by running it through the screen again.
Just before application, in the fall, we typically turn the pile by running it through the screen one last time. This allows us to screen out most undesirable contaminants which can be found in yard trimmings compost (i.e. small stones, twigs, glass, etc.). It also ensures a well-mixed product and maintaining aeration throughout the pile. Yard trimmings are purchased from GreenCycle, Inc. professionally manages it in windrows. We get the biosolids from Chicago Metropolitan Sanitary District where they anaerobically digest the sludge in large lagoons. Then the material is brought to large drying pads where it is allowed to dry, volatilize gases and turn aerobic.
No bulking agent is added. Combining the mature yard trimmings with the finished biosolids offers an affordable product with a well-balanced chemistry (carbon/nitrogen ratio around 15-20/1) for plant growth. Biosolids test high in estimated nitrogen release, phosphorus, sulfur, iron and magnesium. The yard trimmings test high in potassium and calcium with a fair amount of other cations and minor plant nutrients. Mixed together, the yard trimmings also dilute some of the metals found in biosolids like zinc, copper and aluminum.
Application Methods
During our normal coring of fairways, the process involves these steps: Coring with hollow tines; Breaking up soil cores with a vertical mower; Topdressing with compost; Mixing the soil with compost as it is matted into the surface with a section of chain-link fence; Blowing the remaining tufts of turf and thatch into the rough via a three-point hitch blower; Picking up debris in the rough; and Irrigating the area.
We have been coring fairways this way for several years. Adding the extra step of compost topdressing has not significantly impacted the workload. The cleanup is about the same, and we can still get our targeted nine holes (15 acres) done in one day.
So far, we have results much the same as in the early test plots: Improved turf density and color; Rapid healing of cored turf; Dollar spot suppression; Increased earthworm castings; and thatch reduction have been observed. We continue to monitor the impacts of compost use on turf and maintain computerized spreadsheets to evaluate our results. In time and continued applications, we hope to document improved soil structure and suppression of other diseases.
The procedure used to assure that the compost is optimal for our turf involves a series of tests which analyze chemical, physical and biological activity.
Chemical Analysis — Carbon:Nitrogen ratio < 20:1, best at 15:1; pH at 6.5 – 8.5; None to trace amounts of ammonium, sulfide and nitrite; and Low concentrations of soluble salts, especially sodium.
We strive towards elemental balance and recommended ratios favoring the high side of potassium and calcium. Biosolids need to meet US EPA’s Part 503 technical rule for biosolids. All biosolids are tested for coliform and other diseases. Biosolids composted properly have been heated sufficiently to kill viruses, coliform and other diseases. Metals in biosolids are often high and should be considered.
Physical Analysis – Fine texture < or = 1/8 inch; Light, crumbly structure, parent material nonvisible; Moisture at 30-40 percent; and dark brown to black in color.
Additional Compost Uses
In addition to our fairway compost topdressing program, we also use compost in our ‘soil and seed’ mix for divot repair. Compost is used as topdressing while overseeding turf. In 1998, a 7,000 sq.ft. experimental putting green was constructed having 20 different root zone mixes. Each mix used U.S. Golf Association (USGA) approved sand in a USGA root zone profile with various organic and inorganic amendments. The 90/10 sand/compost plots outperformed the others considerably in seedling establishment and development. We continue monitoring other effects as the putting green matures. Compost tea is made and applied as a protective biofilm on the phylloplane and to deliver plant growth promoting substances.
To apply compost topdressing to fairways we purchased a TY-Crop MH-400 for $20,000. This material hauler/topdresser is used for other tasks as well, such as rapid refill of materials while topdressing greens and tees and applying sand in bunkers. The compost we currently use is a 50/50 mix of yard trimmings compost and biosolids. Our cost for yard trimmings compost is $14.00/cubic yard. For us now, biosolids are freely available (EPA permits are needed). The rate used is approximately 17 yards (7 tons)/acre = 1/8 inch layer. Total material cost $119/acre. We offset some costs by reducing our other fertility inputs and decreasing fungicide treatments as part of our Integrated Pest Management program.
Understanding the chemistry, biology and science of compost is complicated. Parent material used, how it’s managed during composting, and storage can all have a huge effect on the finished product and results. Yet our efforts to understand compost, particularly its microbial benefits, have paid off. Results using composts have been positive, and the turf ecology is improving under our growing conditions.
Dan Dinelli, Superintendent, of North Shore Country Club in Glenview, Illinois can be contacted via e-mail at ddinelli@aol.com.