Seeded Bermudagrass Blends for the Transition Zone.

Improved seeded bermudagrass [Cynodon dactylon L. (Pers.)] cultivars touting enhanced cold tolerance are expanding in use in the United States transition zone. However, high seed cost and slower establishment rates can limit use of the improved varieties. This research was conducted to determine if an improved variety (‘Riviera’) could eventually dominate the turf stand when blended with cheaper, less adapted bermudagrass cultivars (‘Wrangler’ and ‘AZ Common’). Riviera seed was blended with Wrangler or AZ Common at 0, 25, 50, or 75% by weight and seeded at either 24.5 or 49 kg/ha in Blacksburg, VA in 2004 and 2005. All plots received a total of 147 kg N/ha per growing season and were mowed two times weekly at a 1.9 cm cutting height. Data were collected on establishment rates, visual quality, and spring greening characteristics. Beyond initial establishment data where the 49 kg seeding level covered quicker than 24.5 kg, there were no significant differences for measured variables between seeding levels. 100% Riviera treatments established slower than either 100% Wrangler or AZ Common plots, and a linear increase in establishment level was determined as the percentages of the unimproved bermudagrass varieties increased in the blends with Riviera. There was a significant linear trend in spring greening as the % Riviera increased in blends with AZ Common. As anticipated, visual turf quality ratings increased as the level of Riviera increased in both seed blends. The trend analyses indicated highly significant linear trends in visual quality ratings as Riviera % increased in the first growing seasons, but quadratic trends becoming more likely as the study progressed. This suggests that 50/50 and 75/25 % combinations of Riviera plus Wrangler or AZ Common were similar to 100% Riviera plots in quality over time. Under climatic and maintenance conditions in these trials, blending Riviera with lower quality, faster establishing bermudagrasses resulted in Riviera-dominated stands regardless of the blending percentage of Riviera after two growing seasons