Fine fescue naturalized areas add nice contrast to a golf course. They create a transition between tall trees and mown grass and turn golden brown in the summer, which can set off the green color of trees and grass. There are several reasons to incorporate fine fescue areas on a golf course but if they were established too thick, or are allowed to get that way, the benefits might not outweigh the golfer complaints and impact on pace of play.
Applying plant growth regulators (PGRs) to these areas in the spring when seedheads are emerging can help. There are two main options for applications. I’ve seen both work well, therefore I don’t recommend one over the other. The decision on what to use generally comes down to what the superintendent has in inventory.
The standard combination is Primo Maxx (trinexapac-ethyl) and Proxy (ethephon) applied in late spring to early summer. There is flexibility on timing and the best indicator I can suggest is when you first start to see seedheads emerge it’s time to apply. The other option is Trimmit (paclobutrazol). The only difference is the active ingredient for regulation, application timing is the same. A commonality I’ve observed is whichever PGRs are used, applying after a mow helps maintain lower growth and less density.
One common question I get when discussing this topic on USGA Course Consulting Service visits is, “Will we get any seedheads during the summer if PGRs are applied?” The answer is yes! From the fairway or tee, players will still see seedheads that turn golden brown and wispy in the summer. The difference is when you are in there, you’ll notice shorter growth and less density, making finding a ball and advancing it easier. If you would like additional information, including detailed strategies for weed control in fine fescue naturalized areas, please reach out to your regional USGA agronomist.
Northeast Region Agronomists:
Darin Bevard, senior director, Championship Agronomy – dbevard@usga.org
Elliott L. Dowling, regional director, East Region – edowling@usga.org
Brian Gietka, agronomist – bgietka@usga.org