Performance of Tall fescues at Stillwater

Dennis Martin
Extension Turf Specialist

Roseanne Mayo Kuzmic
Department of Horticulture and Landscape Architecture

Joan Ratzlaff French
Department of Horticulture and Landscape Architecture

HLA-6602

Tall fescue (Festuca arundinacea) is the most widely used cool-season turfgrass in Oklahoma. With irrigation, tall fescue usually can provide the consumer with 12 months of green turf. Tall fescue is versatile. It performs well in either full sun or light to medium shade when properly managed.
The purpose of this trial was to evaluate the performance of 65 tall fescue cultivars. The trial was performed at the Oklahoma State University Turfgrass Research Center at Stillwater, Oklahoma from 1988to 1992. The Stillwater site was one of 42 sites nationally that conducted the tall fescue evaluation in cooperation with the National Turfgrass Evaluation Program (NTEP).

The tall fescue trial was established by seeding the grasses into 5 x 5 foot plots at the rate of 4 pounds of seed per 1000 square feet on October 12, 1987. The plots were replicated three times in a randomized complete block design. The study was managed under the conditions described in Table 1.

Performance characteristics were evaluated under the guidelines of the NTEP. Performance characteristics presented in this report are for density, color, and overall quality (Tables 2-4). Color of the grasses was evaluated visually using a 1 to 9 scale, where 1 equaled yellow green and 9 equaled dark green. Color ratings were made during the spring and fall when tall fescue was under the least heat or drought stress and during the time when fescues typically exhibit their best color. Density of the grasses was rated visually using a 1 to 9 scale, where 1 equaled very thin turf and 9 equaled very dense turf. Quality was evaluated each month during the growing season using a 1 to 9 scale where 1 equaled very poor quality and 9 equaled the highest possible quality. Visual quality ratings incorporated the aspects of color, texture, density, smoothness, and uniformity into a single rating value. Visual quality is widely accepted by turfgrass specialists to be one of the single most important measures of turfgrass performance. High visual quality ratings over several years of testing indicate a good adaptation of the variety to the conditions present at the test site.

Data from the trial was subjected to statistical analysis using an analysis of variance (ANOVA) procedure. Data for visual color, density, and quality were averaged for each year and overall five years of the trial. When the ANOVA procedure identified true statistical differences between the grasses at the 95% confidence level, the least significant difference (LSD) test was employed to separate the performance values of the various grasses present. If statistical differences were present, the LSD value was placed at the bottom of each column within each year or at the bottom of the five year average for comparison of turfgrass performance.

To compare the performance of any two turfgrasses within a column, determine if the difference in their performance value is greater than the LSD value listed at the bottom of the column. If the difference between the performance values is equal to or larger than the LSD value, then the grass with the larger value provided statistically greater performance than the grass with the smaller value for the characteristic under consideration. In these tests we are 95% certain that statistical differences present are true performance differences that exist among the cultivars. It is not possible to achieve 100% certainty regarding differences in performance. If the difference between the two means is less than the LSD value provided or if no LSD value is given at the bottom of the column for data of concern (i.e. - - -) then the difference between the performance values is not statistically different. When two performance values are not statistically different, any difference in performance is believed to have been due to random chance rather than one cultivar truly being superior to the other. Cultivar performance is affected by a number of factors such as soil type, climatic conditions, and management practices such as mowing, fertilization, and irrigation. Differences in performance results may occur when growing the grasses under conditions other than those used in this five year evaluation.

New cultivars of tall fescue become available each year. Many of the new cultivars available were tested in the 1988-1992 trial under their commercial name or under an experimental designation. If a tall fescue grass of interest is not listed in Tables 2-4 , make certain the grass is not a blend of two or more tall fescues. Examine the marketing literature and seed label, or contact your seed vendor to determine the components of tall fescue blends. Blends of cultivars were not evaluated in this test, however, the individual components of a blend may have been tested. Blends of cultivars are not tested due to the impracticality of evaluating the large numbers of combinations possible. Some newly released cultivars may have been tested in the 1988-1992 evaluation but under an experimental number designation. Many trade flyers will list the experimental designation that cultivars were tested under in NTEP trials.

Current tall fescue cultivar recommendations can be found in “OSU Extension Fact Sheet F-6418:Selecting a Turfgrass For Oklahoma,” while management suggestions can be found in “OSU Extension Fact Sheet F-6420: Managing a Lawn in Oklahoma”.
The authors wish to acknowledge the assistance of Joel Barber, Kellie Curry, Mike Kenna, William Marotta, Kevin Morris and the National Turfgrass Evaluation Program for their assistance in conducting the 1988-1992 tall fescue trial at Stillwater.