Key Takeaways:

• Rising maintenance costs and a desire to improve operational efficiency are changing how golf courses maintain their rough.
• New technologies, like the USGA GPS Service, can identify site-specific opportunities for introducing low-maintenance rough at golf courses.
• Reducing fertility, using an integrated pest management approach, and applying materials that suppress growth can significantly improve maintenance efficiency in low-play rough areas.
• Before adjusting maintenance practices in the rough, it is important to set clear expectations so key course personnel are aligned with the objectives and likely outcomes.
  
  

The key is to explain what could happen if certain maintenance practices are adjusted before implementing changes. Presenting both the benefits and negatives, along with the rationale for proposed changes, can help improve receptivity among golfers and course officials. For instance, reducing fertility should result in less mowing, but the turf may also be less tolerant of golf cart traffic and could become less dense overall. Tracking and regularly sharing year-to-date cost savings, the impact of reallocated labor hours, and improved efficiencies that have developed from adjusting rough maintenance is advised. This information is powerful because it highlights the reasons behind any changes golfers might notice.

Identifying Areas for Reduced Inputs

Golfer expectations have increased for all areas of a golf course, including the rough, but it is clear that not all areas within the rough receive similar amounts of play. For instance, the rough around greens comes into play much more often than the rough around tees. Therefore, reducing rough inputs around the tees is a good place to focus on first. Scaling back maintenance of the green surrounds and bunker banks is not advised unless you can do so with minimal risk of even a slight reduction in turf quality.

Most courses probably have a few acres of rough between holes that receive very little play and thus could be maintained using fewer inputs with minimal impact on the golf experience. Using tools like the USGA GPS Service to better understand golfer traffic patterns can identify low- and high-play areas. The data can be used to confidently scale back specific maintenance inputs in low-play areas knowing these changes will not have much impact on playability. Those resources can then be reallocated to high-priority areas.

Graduated rough, where turf closer to the fairway is maintained at one mowing height and rough farther away is maintained at a taller height, has been used during many USGA championships. In a championship setting, the goal is to provide more penalty for shots hit farther off line, but this approach is also used at many golf courses to improve mowing efficiency. Many superintendents try to get all the rough on the course mown early in the week. When there is not enough staff time available to mow all the rough a second time during the week, employees are often instructed to mow one or two laps around each fairway again to ensure rough close to the fairways is cut before busy weekends. The graduated rough concept is an easy way to save on mowing time in peripheral areas, but why not consider reducing other inputs in these locations as well?

Easy Ways to Save Money

The remainder of this article presents several strategies that could save costs and improve maintenance efficiency. Some strategies are broadly applicable while others are specific to a certain grass species. The options outlined may not be right for every course, but it is almost certain that there is some low-hanging fruit at your facility where adjustments to rough maintenance can improve operational efficiency with minimal impact on playability.

Mowing Frequency and Height of Cut

Mowing frequency and the height of cut are closely related. The lower the height, the more often turf needs to be mown to avoid scalping. Maintaining a mowing height of 2 to 3 inches is common for most cool-season rough, and often requires mowing one or two times each week. To save costs, reduce the mowing frequency to once a week at the most. For irrigated rough, scaling back the amount of water applied will make it easier to reduce the mowing frequency because the grass will not grow as quickly. If low-play rough areas are non-irrigated, a mowing height around 3 to 4 inches could be used during summer because the growth rate would be low and the stand would probably become thin, which would allow for a mowing frequency of seven to 14 days at a higher height of cut. In parts of the country that receive abundant rainfall, raising the mowing height may prove to be more challenging because turf actively growing at 3 to 4 inches could be too penal and may cause pace-of-play issues.

Bermudagrass is the most commonly used rough species in southern parts of the U.S. (GCSAA, 2017). This species grows rapidly during summer, often needing to be mown one or two times per week at a height of 1.25 to 2 inches. Because of the dense turf canopy, a higher mowing height is likely to create very difficult conditions for most golfers. Unlike cool-season rough, raising the mowing height of bermudagrass rough in an attempt to reduce mowing frequency is not typically an option.

Mowing Equipment and Striping

Using the most-efficient mowing equipment for the rough will result in significant labor and fuel savings. Using wide, pull-behind units for rough mowing has been a game changer for many facilities. It goes without saying, but a mower with an 11-foot-wide deck is far more efficient than a mower with a 6-foot-wide deck. Small mowers are an important part of the equipment fleet, but they are best suited for areas with terrain that cannot safely accommodate larger equipment. It is also worth noting that elaborate striping patterns in the rough are probably not the most efficient mowing options, so adjusting to a simpler mowing pattern could yield significant savings.

Fertility

In low-play rough, fertilizer applications should be made infrequently – and may not be needed at all. Potassium and phosphorus should only be applied if a soil test determines there is a deficiency and the turf quality is poor. Nitrogen applications will improve turf density and vigor, but will also increase the need for mowing. Without any nitrogen applications over several years, the rough may thin out to unacceptable levels. However, the cost savings and reduced mowing associated with reducing nitrogen likely outweigh the concerns. After all, nitrogen can always be applied if the stand starts to thin beyond acceptable levels. If nitrogen is applied, consider using products that have a slow or controlled release over a period of 60 to 120 days. This approach might provide enough growth to maintain desirable conditions without creating a flush of growth that could create the need for additional mowing.

Plant Growth Regulators

To reduce the need for frequent mowing and blowing clippings, and to reduce the risk of scalping, some courses apply plant growth regulators in the rough. Growth regulators like trinexapac-ethyl are effective at reducing turf growth and mowing frequency but require applications every two to four weeks. This can be costly and time consuming given the challenges of making a broadcast application to more than 50 acres of rough. Also, growth regulator applications may not always result in reduced mowing. For instance, if there is a high population of weeds, the normal mowing frequency may still be necessary when using trinexapac-ethyl because it does not have activity against weeds.

Certain herbicides can also provide excellent growth regulation for bermudagrass, so it may be worth looking at a different approach to reducing turf growth. The herbicide imazapic, although not safe on cool-season turf and not known for enhancing turf quality, can reduce the growth of bermudagrass for four to six weeks and control weeds at a cost of around $1 per acre. Conversely, depending on the brand and rate applied, it could cost around $16 per acre or more for trinexapac-ethyl, which does not suppress weed growth and may only provide two to four weeks of growth suppression. Trinexapac-ethyl does, however, increase turf quality and density while imazapic can cause temporary discoloration. However, some courses have said their golfers like the color contrast and visual definition between the rough and fairway after imazapic has been applied. Another benefit of using imazapic is that it may reduce the need for preemergence and postemergence herbicide applications. For courses with bermudagrass rough, imazapic could be an attractive alternative to trinexapac-ethyl when you factor the reduction in mowing, added activity on weeds and lower cost.

Weeds

An Integrated Pest Management (IPM) approach is ideal for rough, especially low-play areas. An IPM program incorporates pest threshold levels and both cultural and chemical control options when necessary. Frequent scouting and record keeping will help to identify the consistent problem areas, and then they can be ranked based on the level of play they receive. For weed management in low-play rough, skipping preemergence herbicide applications completely, or only treating areas with a history of weed issues, falls in line with a sound IPM program. Spot applications for postemergence control can be labor intensive, but they also result in significant chemical savings compared to broadcast applications. For difficult-to-control weeds like knotweed, sedges and grassy weeds, develop a tolerance threshold to determine when herbicides will be needed to preserve the stand of turf.

Insects

An IPM approach should also be used to manage destructive insect pests in low-play rough. White grubs, chinch bugs, mole crickets, armyworms and sod webworms are common insects that can be a concern for rough areas. Frequent scouting for insect activity helps ensure that curative applications can be made before significant damage occurs. Wall-to-wall applications are rarely needed and are typically only necessary if there has been a history of significant, widespread insect damage. Free or inexpensive mapping software can help you pinpoint the location of past pest activity, making it easier to spot treat areas with greater confidence.

Diseases

Disease can be troublesome in the rough, especially if Poa annua and perennial ryegrass are present. However, because of their cost, fungicides are seldom applied to the rough at most courses. Diseases like dollar spot and brown patch often cause only minor playability issues, so it makes sense to reduce fungicides targeting these diseases first. If your course has a history of Pythium or gray leaf spot, fungicides should still be applied to avoid significant turf loss. However, an IPM approach should still be taken when trying to control these diseases in rough areas because certain parts of the course are often more susceptible than others.

Introducing Low-Maintenance Grasses

Cool-season grasses used for roughs typically include fine fescue, turf-type tall fescue, Kentucky bluegrass and perennial ryegrass. Poa annua populations can be high in roughs, but this species is quick to die during stressful weather. Fine fescue and turf-type tall fescue perform well under low-input management programs, making them a great choice for rough in northern areas. Introducing these species into low-play rough may be challenging, but the long-term benefits are worth it. Slice-seeding or core aeration followed by overseeding in the fall is a good method of introducing stronger grasses into the rough. Completely renovating problematic rough areas by applying nonselective herbicides and reseeding should also be considered. This method will produce quicker results, and can be done while keeping the course open for play with careful planning and communication.

For those in southern areas, converting the rough to lower-maintenance, slower-growing grasses like bahiagrass, centipedegrass, buffalograss or kikuyugrass should be considered. These grasses may not produce the same playability as bermudagrass, but they require fewer inputs to maintain acceptable playing conditions. These grasses also present a visual and playability contrast to the fairways.

Converting Maintained Rough to Naturalized Areas

This article has focused on reducing inputs to in-play rough, but at many courses there are probably a few spots that could be converted to naturalized areas that receive little to no maintenance during the entire year. Naturalized areas often only need to be mown once or twice a year and may not need any applications of fertilizer or pesticides depending on expectations. To truly save costs and improve efficiency, naturalized areas should be natural. Weeds are probably going to develop and it may not be easy to find a golf ball in them but, if installed in the right area, these are not significant issues at most golf courses.

Conclusion

There is always a balance that needs to be achieved between golfer expectations and what a course can afford. Some golf courses can afford the expenses associated with producing high-quality rough throughout the entire property, but most cannot and have to be more selective with how they allocate inputs. The cost of products, fertilizers, equipment and labor are likely to continue increasing, so it is prudent to consider rough maintenance adjustments that can achieve cost savings without significantly impacting playability and aesthetics in low-play areas. 

Through the Course Consulting Service and GPS Service, the USGA can provide course-specific recommendations and data to help you introduce low-maintenance rough at your course. Visit our Solution Center for more information.

Steve Kammerer, Ph.D., is a senior consulting agronomist in the Southeast Region and Adam Moeller is the director of Green Section Education and an agronomist in the Northeast Region.