Biochar-organic amendment mixtures added to simulated golf greens under reduced chemical fertilization increase creeping bentgrass growth

Authors: Vaughn, Steven; DINELLI, F - North Shore Country Club; Jackson, Michael - Mike; Vaughan, Martha; Peterson, Steven - Steve

Submitted to: Industrial Crops and Products
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/19/2017
Publication Date: 11/27/2017
Citation: Vaughn, S.F., Dinelli, F.D., Jackson, M.A., Vaughan, M.M., Peterson, S.C. 2018. Biochar-organic amendment mixtures added to simulated golf greens under reduced chemical fertilization increase creeping bentgrass growth. Industrial Crops and Products. 111:667-672.

Interpretive Summary: This research demonstrates that grass grown for golf greens grows better when the sand under the greens is supplemented with biochar (agricultural charcoal) or municipal waste. United States Golf Association (USGA) specifications for the construction of golf greens consist of a topsoil mixture of a minimum of 80% sand to provide sufficient drainage to keep the courses playable. Organic matter, most commonly sphagnum peat moss, is added to provide desired water and nutrient retention for satisfactory turf performance. However, because peat decomposes over time, its effectiveness is limited and requires putting greens need to be rebuilt frequently. Unlike other organic amendments, biochar is resistant to microbial degradation and therefore should have great longevity in golf greens. In this study, mixtures of sand and peat, biochar, and various composts were evaluated for their effect on the growth of creeping bentgrass in simulated golf greens meeting USGA standards. Forty days after seeding, it was found that plants grown in 5% biochar and 10% Metropolitan Water Reclamation District biosolids had significantly greater growth. Growth was also better than bentgrass grown in a commercially-available biochar/compost (CarbonizPN-Soil) product. Based on these results the addition of both of these biochar-compost mixtures would improve overall plant growth on putting greens at reduced cost to managers of golf courses.

Technical Abstract: Simulated golf greens were used to test the growth of creeping bentgrass (Agrostis stolonifera L. "007") receiving suboptimal chemical fertilization in sand based substrates amended with 15% peat (control), a commercial biochar, a commercial biochar-compost (CarbonizPN), or seven formulated biochar-compost mixtures. Physical and chemical properties including pH, bulk density, pore space, compaction distance, nutrient content and water/nutrient retention capacity varied among the mixtures. The height, root length, and fresh and dry weight of Bentgrass plants grown in polyvinyl chloride tubes containing the different substrate mixtures mimicking a United States Golf Association root zone were evaluated and compared. Forty days after seeding, plants grown in 5% biochar and 10% Metropolitan Water Reclamation District biosolids had significantly greater fresh weights, dry weights, and shoot heights than the control. Dry weights and shoot heights were also higher than the control in bentgrass grown in the 15% CarbonizPN mixture. Based on these results the addition of these biochar-compost mixtures would improve overall plant growth in sand-based root zones under reduced chemical fertilization.