Golf Course Management

MAY 2014

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/302556

Contents of this Issue

Navigation

Page 82 of 155

76 GOLF COURSE MANAGEMENT 05.14 Which Kentucky bluegrass cultivars perform better with less water? Twenty-eight Kentucky bluegrass cultivars and two hybrid bluegrasses were tested for their ability to retain visual quality under reduced irrigation. Field research at Kansas State University indicates that water require- ments may differ signifcantly among cultivars of Kentucky bluegrass (Poa pratensis L.), depending upon desired turfgrass quality. Given the certainty of periodic drought, limited water availability and increasing irrigation costs, having choices of Kentucky bluegrass cultivars that may maintain better quality with less water is an attractive option. Ideally it would be helpful to select a turfgrass that can perform well with less water. A helpful concept when discussing Kentucky bluegrasses is their classi - fcation into phenotypic groups. Individual cultivars of Kentucky bluegrass are classifed into phenotypic groups based on common growth and stress performance characteristics gathered from feld trials (1). Previous research has indicated that such groupings may be useful in predicting drought tol - erance. Because cultivar turnover is rapid in the turfgrass industry, deter- mining the relative irrigation requirements of phenotypic groups may en- able researchers to predict irrigation requirements of cultivars not included in any particular study. Using a rainout shelter, we compared seasonal irrigation amounts among 28 Kentucky bluegrass cultivars for two growing seasons. By shielding plots from rainfall, water could be withheld until wilt symptoms were evident. Our objectives were to identify Kentucky bluegrass cultivars and phenotypic groups that maintain better visual quality with less irrigation, using wilt- based irrigation. We hypothesized that if visual quality were good at the beginning of the season, we would maintain minimally acceptable quality in Kentucky bluegrass (for example, for a moderately maintained lawn or golf course rough with in-ground sprinklers) by irrigating when at least 50% of a given cultivar showed signs of wilt. Two hybrid bluegrasses (Poa ara nifera Torr. × P. pratensis) were also included in the study. Methods This study was conducted at the Rocky Ford Turfgrass Research Center near Manhattan, Kan. Data were collected for 105 days in 2007 (June 19- Oct. 1) and 108 days in 2009 (June 22-Oct. 7). Turfgrasses included 28 Kentucky bluegrass cultivars and two hybrid bluegrasses (Table 1). Com - mercially available cultivars of Kentucky bluegrass were selected to include representatives from major Kentucky bluegrass phenotypic groups (in the results section, only groups with three or more cultivars were used when This research was funded in part by the United States Golf Association. Dale Bremer, Ph.D. Steve Keeley, Ph.D. Jack Fry, Ph.D. Jason Lewis, Ph.D. Well-watered plots are shown at the beginning of the dry-down study on June 4, 2007 (top). Kentucky bluegrass plots with obvious drought stress are shown at two months into the study, Aug. 4, 2007 (bottom). Plots were sheltered from precipita - tion by the rainout shelter (upper left in each photo), which automatically moved on tracks to cover the plots during rainfall. Photos by Jason Lewis 076-087_May14_TechwellCuttingEdge.indd 76 4/16/14 2:53 PM

Articles in this issue

Archives of this issue

view archives of Golf Course Management - MAY 2014