COURSE CARE
Overseeding Preparations: Scalp Is Out October 2, 2012 By Brian Whitlark

(L) The Amazone seeder is able to seed at a wide range of rates (up to 1,150 lbs per acre for perennial ryegrass) and covers about one acre per hour. (R) Two sets of reciprocating tines scratch openings in the bermudagrass canopy for seed to drop 

The most recent trend in preparing bermudagrass tees, fairways and approaches for overseeding in the Desert Southwest is to do less aggressive preparation. The days of scalping the bermudagrass down to the soil are gone. This update shares two strategies for overseeding that require substantially reduced labor and resources when compared to historical methods.

1. Burn-down herbicidesDr. Jim Baird, University of Riverside, Calif., compared burn-down herbicides (Scyth®, Reward® and Finale®) to traditional scalping methods in preparation for overseeding in the fall of 2011.

  • Burn-down herbicides resulted in approximately 75 percent reduction in green waste when compared to traditionally employed scalping methods.
  • Turflon Ester® applied prior to using Scythe® or Reward® enhanced bermudagrass suppression. Finale® suppressed bermudagrass the longest and its effect was not enhanced with Turflon Ester®.
  • Although Scythe® burns turf the fastest, the research suggests that Reward® offers the best combination of cost, bermudagrass growth suppression, green waste reduction and speed of activity.
  • Researchers suggest that Reward® should be applied at 32 oz per acre, two to five days prior to scalping and the soil should not be allowed to dry prior to seeding.
  • None of the herbicides resulted in delayed bermudagrass recovery in the spring of 2012 (personal communication, Dr. Jim Baird).

 2. AMAZONE seeder – Golf course superintendents in the Desert Southwest and California’s Central Valley have expressed interest in the Amazone seeder. Although this piece of equipment is new to the region and the results are unproven at the moment, the idea of very minimal scalping while producing a quality ryegrass overseed is appealing.

  • The Amazone drill seeder is equipped with two sets of reciprocating tines that scratch open the bermudagrass canopy. Seed is dropped behind the tines, which is followed by a roller.
  • The Amazone seeder is six feet six inches wide, can seed at a wide range of rates and seeds one acre per hour. The cost is approximately $220 an acre to outsource this service and the unit is available for purchase at approximately $21,500.
  • The primary benefit is very little preparation of the bermudagrass is required (suggested to mow at .400- to .500-inch prior to seeding).
  • It is too early to say whether the tool will produce fairways comparable to traditional seeding methods, but results so far are encouraging.

These two strategies offer alternative methods to prepare bermudagrass for overseeding to reduce green waste, improve air quality, reduce equipment wear and minimize labor hours.

For more tips on preparing bermudagrass for overseeding or other agronomic advice, please do not hesitate to contact Mr. Pat Gross: pgross@usga.org  or Mr. Brian Whitlark: bwhitlark@usga.org, or call the Southwest regional office at (714) 542-5766.