Successful Bermudagrass Overseeding is Dependent on Species Selection and Pre-plant Cultivation Technique.

Overseeding cool-season turfgrass into dormant-warm-season turf is a practice implemented by turfgrass managers to improve aesthetics and provide an actively growing playing surface.  This study was conducted to determine the effects of three pre-plant cultivation techniques and traffic on the establishment of five overseeding turfgrass species.  In September 2007, five overseeding species [annual ryegrass (Lolium multiflorum Lam.), intermediate ryegrass (Lolium hybridum Hausskn.), meadow fescue (Festuca pratensis Huds.), perennial ryegrass (Lolium perenne L.), and tetraploid perennial ryegrass (Lolium perenne L. 2n=4x=28)] were established into ‘Riviera’ bermudagrass [Cynodon dactylon (L.) Pers.] that received three different pre-plant cultivation techniques including core-aerification, vertical mowing, and an untreated control. Overseeding grasses were seeded at manufacturer recommended rates.  Overseeding turf coverage differed between species and pre-plant cultivation techniques, but no interaction existed between species and cultivation.  Plots aerified before seeding resulted in the greatest overseeding turf coverage when rated in November 2007 and March 2008.  Perennial and annual ryegrass overseeded plots had the highest turf coverage when rated in November 2007, however, annual ryegrass was less than perennial ryegrass in March 2008. Traffic was more damaging when applied 4 WAP (weeks after planting) than 1 or 2 WAP. There was an interaction between species and traffic with perennial ryegrass less affected by traffic timing than other species. Based on this trial, turf coverage was greatest when aerifying before overseeding dormant bermudagrass with perennial ryegrass.