Golf Course Management magazine is dedicated to advancing the golf course superintendent profession and helping GCSAA members achieve career success.
Issue link: http://gcmdigital.gcsaa.org/i/766215
01.17 GOLF COURSE MANAGEMENT 135 CUTTING EDGE Teresa Carson Evaluating zoysia-tall fescue mixtures in the transition zone Zoysiagrass, a C 4 grass, is more drought- resistant than C 3 grasses, but consumers may object to its brown color during dormancy. Mixing seeded zoysiagrass and tall fescue could improve stand performance and add green color in winter. A study at the Rocky Ford Turfgrass Research Center in Manhat - tan, Kan., evaluated mowing height and tall fescue seeding rate and time of establishment in a stand of seeded zoysiagrass. In the split- plot design, mowing height (0.75 or 2 inches) was the whole-plot treatment factor, and tall fescue seeding rate and time were arranged in a two-way factorial in subplots. Compa - dre zoysiagrass was seeded in all plots at 44 pounds of pure live seed (PLS)/acre in June 2015. Corona tall fescue was seeded in sub - plots at 88, 176 or 352 pounds PLS/acre either in June 2015 with the zoysiagrass seed, or in September 2015 into established zoysiagrass. In mid-November 2015, green cover in the mixtures ranged from 17% to 45%, but a mo - nostand of Meyer zoysia had only 11% green cover. Percentage of tall fescue in the mixture was determined in December, when zoysia - grass was fully dormant. Seeding tall fescue with zoysiagrass in spring generally resulted in poor tall fescue establishment, regardless of rate, but seeding tall fescue in fall into zoy - siagrass mowed at 0.75 inch resulted in 51% tall fescue incidence on grid counts and 5.7% green cover for digital image analysis, the highest of all treatment combinations. Seed - ing tall fescue at 352 pounds/acre in Septem- ber into established zoysiagrass mowed at 0.75 inch provided higher levels of green coverage the first fall following seeding compared with other treatment combinations. — Mingying Xiang (firstname.lastname@example.org); Jack D. Fry, Ph.D.; and Megan M. Kennelly, Ph.D., Kansas State University, Manhattan Spatial variability of soil characteristics warrant site-specific fertility Six fairways (three per location) were sam- pled at the University of Georgia golf course in Athens, Ga., and The Georgia Club golf course in Statham, Ga., during the summer of 2015. Soil cores were collected on a 20-foot grid generated in ArcMap and geo-referenced using a hand-held GPS unit. Approximately six to eight cores were collected and consoli - dated for each point using a 1-inch soil sam- pler to a depth of 4 to 5 inches. Samples were analyzed for soil texture (% clay), pH and OM (%). Interpolated point values for each parameter were modeled using Gaussian pro - cess regression and enhanced by Jenks natu- ral breaks optimization to produce maps that showed significant spatial variability: UGA golf course [% clay (min: 0.4%, max: 25.1%), pH (min: 4.6, max: 6.1), OM (min: 3.2%, max: 19.5%)] and Georgia Club [% clay (min: 2%, max: 29.1%), pH (min: 5.7, max: 7.3), OM (min: 0.1%, max: 17%)]. Maps can be used to implement variable rate fertility, fur - ther increasing application efficiency and re- ducing overall inputs. — Becky Grubbs and Gerald Henry, Ph.D. (email@example.com), Univer- sity of Georgia, Athens Editor's note: An earlier version of t e first sum- mary was publis ed in t e 2016 ASA-CSSA- SSSA Meeting Abstracts, ASA, CSSA and SSSA, Madison, Wis. Teresa Carson is GCM 's science editor. Photo by Mingying Xiang Illustration courtesy of Gerald Henry