The ultimate troubleshooter

With the never-ending evolution of plant growth regulators (PGRs), superintendents are constantly finding new uses for this ultimate troubleshooter.

While acres of fairways and rough can be mowed in relatively short periods of time, it’s often bunker and pond or river edges, as well as trim work around irrigation heads and cart path curbs that eat up valuable man hours and greatly affecting the budget.

Less time devoted to string trimming means man hours can be spent elsewhere -- a point not lost on Jeff Atkinson, portfolio leader for SePRO’s Turf & Landscape Solutions. “Labor is the single largest line-item in a superintendent’s budget, thus accomplishing more with the labor force you have is a priority,” Atkinson says. “Finding ways to utilize PGRs around the course to reduce labor in areas requiring frequent maintenance or difficult-to-maintain areas is a great way to use technology to open up labor for other tasks around the course.

Edgeless, a combination product of Flurprimidol and Legacy from SePRO, is commonly utilized for this purpose, Atkinson adds. “This use of PGRs makes great sense for other areas, also,” he says. “A tremendous amount of time is spent string trimming and irrigation-head edging. Using Edgeless to reduce time spent on these tasks is another great labor-saving use pattern.”

Tim Palko, superintendent at Boulder (Colo.) Country Club, has used PGRs on greens, tees, fairways and approaches throughout the season. Palko and his team have also begun using them around trees and curbing to reduce the frequency in which they need to string trim, which has benefitted his bottom line.

“I’m happy with the formula we found for trim work and will start that earlier next year,” Palko said. “This year we worked on finding rates and combinations that gave us the most regulation without discoloration or turf loss. We found a combination and rate that works for us and it helped free up some man power for other tasks on the course.”

That said, Palko doesn’t expect to add bunkers to his routine at the moment. “I only fly-mow bunkers once a week as it is,” he said. “Although I have experimented with PGRs in the rough, I doubt I will use them on bunker faces specifically. Not being able to ensure uniform application because of the shape of the bunkers makes it not worth it to me.”

The use of PGRs around bunker edges to alleviate fly-mowing frequency depends on the course and the goals the superintendent is trying to achieve, says Bert McCarty, professor of turfgrass science at Clemson University. “If it’s a question of just reducing fly-mowing frequency, higher rates of traditional PGRs such as flurprimidol or herbicides at lighter rates are often used,” he says. “If turf quality is a concern (as it most often is), then combinations of such products at lighter rates with trinexapac-ethyl helps alleviate turf quality concerns.”

Spraying PGRs around irrigation heads, curbs and ponds -- or other aquatic edges -- to control turf and vegetation growth requires a higher level of caution because they are often sensitive environmental sites, McCarty says. “Around irrigations heads, these soils typically stay wetter for longer periods of time resulting in more turf growth and/or weed invasion,” he says. “So, PGR and/or weed control programs need to be adjusted in these sites, accordingly. Along pond edges, applicators need to use products labelled for these areas and ensure sprayer calibration is correct to prevent overspray. For example, using higher than label rates may damage the turf, thus making treated areas more prone to soil erosion.”

Atkinson believes PGR use patterns will continue to emerge.  “Superintendents will continue to tinker, and SePRO will continue to participate in R&D initiatives,” he says. “As the golf course industry shifts to more environmentally sustainable agronomic practices, PGRs will be a vital part of these programs.”

McCarty agrees, adding as the technology evolves, budgets get tighter, and end-users become more innovative in product capabilities, more PGRs are being used. “For example, in an effort to save mowing costs in out-of-play areas and in some roughs, superintendents are using lighter rates of certain herbicides to act as PGRs in reducing plant growth and seedhead production, thus, requiring less mowing, he says.

Determining the success of a PGR program is often a moving target. One man’s floor may be another man’s ceiling.

“Measuring efficacy of a PGR program really depends on what the particular agronomic goal is,” Atkinson says. “While not always feasible, it’s very useful to leave a non-treated check area to compare treated areas to see if you’re getting the desired effect from PGR applications or any other input of an agronomic program. Having a non-treated area allows for easy comparison of growth responses following a PGR application.”

At Boulder Country Club, Palko set up tests areas on its par-3 course to figure out if the manpower-saving benefit of PGR use is better suited for trees, curbs and fence lines rather the than bunkers.

With or without the benefit of a “test course,” McCarty advises novice users should use lighter rates for the first several applications. “In many cases, applying the full rate initially ‘shocks’ the plants, causing discoloration (e.g., bronzing) and distorted growth patterns,” he says. “For such situations, I suggest initially applying one-half the intended full rate followed by three-quarters full rate with the second application and finally, by the third application, it usually is safe to use the intended full rate. Otherwise, today PGRs [have] come a long way in terms of reduced risks compared to some of the earlier products and is a reason more are being used.”

Rob Thomas is a Cleveland-based writer and frequent GCI contributor.