Viridescent - the Asian Turfgrass Center blog

Golf Course Renovation, Grass Selection, & Manilagrass

I visited the Philippines a few times last month and was again impressed by how well manilagrass (Zoysia matrella) performs there. The classic East Course at Wack Wack Country Club in Manila is undergoing a restoration project that leaves the manilagrass greens untouched. The grass on these greens is relatively free of disease, has a very low fertilizer requirement, and provides a fast and firm putting surface. By using native grasses on the fairways (primarily Axonopus compressus, known as Carabao grass in the Philippines) and on the greens, Wack Wack CC's East Course provides a classic test of golf and uses grasses that require almost no inputs apart from mowing and irrigation.

Why do I mention these grasses? Because the use of the native grasses is surprisingly uncommon when golf courses are built or renovated in Southeast Asia today. There are some situations where bermudagrass (Cynodon) may be the right choice, and there are occasions when seashore paspalum (Paspalum vaginatum) is the right choice, but for many golf projects, using native grasses such as zoysiagrass or carpetgrass would be a better choice. Why?

• The native grasses require less fertilizer than bermudagrass or seashore paspalum
• The native grasses are generally more resistant to diseases, insect, and weed invasion than or bermudagrass or seashore paspalum
• Pesticide use on native grasses is minimal
• It costs a lot less to maintain native grasses
• Some of the best courses in Southeast Asia use them! Sentosa GC in Singapore has zoysia fairways and roughs, the aforementioned Wack Wack CC has carpetgrass and the greens are zoysia, Hong Kong Golf Club has carpetgrass and zoysiagrass on most of the property, and the best new course in Asia Pacific for 2009, Banyan Golf Club in Thailand, uses native zoysia for fairways and roughs
• The course presentation and playability with native grasses is still very good
• There is a lot more flexibility in the maintenance when native grasses are used

What do I mean by "flexibility in maintenance"? Above we see a native manilagrass (Zoysia matrella) lawn beside swimming pools at the Anvaya Cove development near Subic Bay. At the swimming pool, with virtually no maintenance, zoysia is a foolproof grass. It just grows along, slowly, providing the desired groundcover. Below we see the exact same grass at the Manila American Cemetery and Memorial (as an aside, do go there if you are ever at Manila -- the cemetery is a beautiful, quiet, and moving place, with 17,202 graves of military dead of WWII).

The native grasses can be maintained to look green and lush, or dry and close-cropped to the ground, and the native grasses don't die. There is less flexibility with imported bermudagrass or seashore paspalum. Without the optimum amounts of water, fertilizer, and pesticides, the bermudagrass or seashore paspalum cannot provide a good playing surface in Southeast Asia. With native grasses, there is a lot of flexibility in the type of surface that can be created. But don't try to get too flexible with seashore paspalum or bermudagrass, or those grasses will fail.

Five Ways to Improve Turfgrass Conditions

I can actually think of ten simple ways to improve turfgrass conditions -- these are only the first five ways, and I will write more later about another five ways to improve grass. The article I wrote on this topic has been published in Golf Business Asia and can be downloaded here. So what do I think are the first five ways to improve turfgrass conditions?

1. Set course maintenance standards. If we have a certain level of grass quality, and want to reach an improved level of playability or appearance, we need to define what that standard is and what work must be implemented in order to achieve the desired quality level. For more details, an article I wrote on this topic can be downloaded here in English and downloaded here in Chinese (中文). A simple example is grass quality and tolerance of weeds in the fairways. If there is no standard for this, than at what weed threshold are the fairways acceptable, or unacceptable? When I was a golf course superintendent I was not a big fan of these types of standards, thinking them extraneous, but I now think that written standards, no matter how simple, are the starting point for any turfgrass management (or turfgrass improvement) program.

2. Choose the right grass. I cannot overemphasize this enough. There are certain grasses that are well-adapted to certain growing conditions and that can be managed to provide the desired playing surface. There are other grasses that are less well-adapted to your growing conditions and that require a tremendous amount of maintenance in order to produce the desired playing surface. Or perhaps you struggle to achieve the type of playing surface that you want. Would a different species of grass or an improved variety of the one you are currently growing help to improve turfgrass conditions? It seems like a lot of wasted resources to manage grass that is not well-adapted to your site. For more information about this, you can search for the information you are looking for. There are some excellent turfgrass specific information resources available online, and I wrote about the best of them (in English) and you can also download the article about information resources in Chinese (中文). Also, you may wish to read an article I wrote for Golf Business Asia about managing and choosing warm-season grasses. And you can see a selection of photos of different warm-season grasses, along with some advantages and disadvantages of each, at this photo gallery.

3. Fertilize the right amount. This is critical for improving the grass. If I want to be healthier, one of the first things the doctor will tell me to do is to evaluate my diet, right? And I should eat a balanced diet with the right amount of fruits and vegetables and vitamins and minerals and so on. Well, grass is the same way, except it is a lot simpler. With grasses, we can conduct a routine soil nutrient analysis (a laboratory test of the soil's chemical properties) to determine how much of the essential plant nutrients are present in the soil, and how much should be added as fertilizer. In many soils, there is already enough phosphorus to meet the needs of the grass, and in some cases there is enough potassium as well. If there is not enough, then we simply add more. The key element to get right in the fertilization program is nitrogen. This is like me, if I am on a diet, being concerned about how many calories I eat every day. Eating more calories than I burn each day will make me gain weight, while burning more calories than I eat results in me losing weight. If the grass gets too much nitrogen it will grow too quickly, and if the grass doesn't have enough nitrogen it will become yellow and grow too slowly. The goal is to control the growth rate of the grass to create the desired improvement to turfgrass conditions by applying exactly the right amount of nitrogen. For many grasses, a good starting point for the amount of nitrogen to apply is about 3 g N m^-2 month^-1, during the seasons when the weather is conducive to vigorous grass growth. The exact amount of nitrogen to apply can be adjusted based on the turfgrass performance. For more information about this, see this article I wrote for Golf Course Seminar (in Japanese, 日本語) or this article from the Hawaii GCSA newsletter.

4. Mow with a plan. After choosing the right grass and applying the right fertilizer, there is no way to get the desired quality without mowing properly. That means using mowers with sharpened blades, set at the proper mowing height, and operated at the optimum mowing frequency for a particular area. And as long as the mowers are going to be sent out to mow the grass, why not mow an attractive pattern into the grass? This may be a type of stripe or checkerboard or even no stripes at all, but it takes a plan to achieve the desired appearance after mowing. Get the mowing right and the grass conditions will almost certainly improve.

5. Keep the grass as dry as possible. Or perhaps more accurately, keep the soil as dry as possible. How is that going to improve turfgrass conditions? If the soil is kept dry, there will be more air space in the soil. When the water content of the soil is high, there is not much space for air. Grass roots grow better when there is plenty of air space in the soil, and if you can establish a healthy root system, the playing surfaces will be more stress tolerant and the grass plants will be more healthy. To really manage the soil moisture, I find it is extremely useful to use a soil moisture meter such as the Hydrosense from Campbell Scientific, the Theta-Probe from Delta-T Devices, or the TDR Meters from Spectrum Technologies. For most turfgrass sites, I like to maintain the soil moisture at more than 10% (by volume) and less than 25%. You can find the optimum range for your site, and by using one of these meters, you can monitor the soils as they dry, only applying water when the soil reaches the critical point when the grass will begin to wilt. I wrote about soil water management extensively in this article for Golf Course Seminar (in Japanese, 日本語) and in Irrigation for Bentgrass Greens: Theory and Practice (for the Kanto Golf Association and also in Japanese, 日本語). If you are interested to know more about this, please send me an e-mail inquiry or leave a comment here.

Waterlogged Soils and Turfgrass Performance

A fascinating project looking at turfgrass growth in waterlogged conditions is being conducted at Singapore's HortPark by graduate student Vivek Govindasamy and his advisor Dr. Kenneth Marcum, Senior Researcher with CUGE Research - Turf Science. At Singapore there is a lot of rain, averaging almost 2.5 meters annually, the soils are often saturated with water, and in low-lying areas with poor drainage the grass is sometimes underwater.

We don't know how different warm-season turfgrass species will respond to waterlogged soils, and Vivek's project will give some idea about which grasses can tolerate waterlogged soils most effectively, and may provide some idea as to what mechanism allows for that tolerance. Grasses are being grown in plastic tubs that maintain water at levels to either mimic normal soil moisture levels, waterlogged soils, or completely immersed turfgrass plants. Among the grasses being tested in these conditions are seashore paspalum (Paspalum vaginatum), zoysiagrass (Zoysia matrella), and carpetgrass (Axonopus compressus).

Vivek is measuring the chlorophyll content of the grass leaves as an index of plant health and will eventually be inspecting the roots to search for possible aerenchyma development in the grasses most tolerant to waterlogged conditions. The results of this research project will be very useful in that they will provide guidance on which grasses should be chosen for planting in areas susceptible to waterlogged soils. The upcoming CUGE International Turfgrass Seminar on 29 and 30 October may provide a chance to learn about some preliminary observations from these experiments.

More Grass Photos From ATC

I have posted a selection of photos of different grasses on the Asian Turfgrass Center photo galleries at flickr. The photo galleries at www.asianturfgrass.com are one of the most viewed portions of the site, and the photos at flickr are easier to find by searching, viewers can leave comments on the photos, and there are more options for viewing and using the photos. I hope you find them interesting, please sign up here to receive updates when new photos are posted, and please let me know if there are any grass-related photos you would like to see.

Zoysia Greens & Fairy Rings

Last week I visited the Sritrang Golf Course in southern Thailand's Trang province. This is a low maintenance golf course on an army base, using native grasses, including a native Zoysia matrella on the putting greens.The green fee is quite affordable, from 300 to 500 baht for visitors, depending on the day of the week. That is about US$15 for an 18 hole round on a rugged course with boldly-contoured greens; a caddy will be about US$7.

I like zoysiagrasses in Southeast Asia because they tend to perform the best with the fewest inputs. Zoysia grows better year round, is healthy in both the dry seasons and in the rainy seasons, and the zoysia tends to choke out some of the weeds that invade other grasses. Zoysia is relatively immune from diseases, and it basically just grows. If I were spending my own money to build and grass a golf course in Southeast Asia, I would in almost all cases choose a type of zoysia.

The only disease I saw on the zoysia at Sritrang was fairy ring. This is a fungus that grows in the soil and creates hydrophobic conditions in the soil. You can see the dry spots in the turf near my feet in the photo at right, and you can see the mushroom growing in the turf. These are typical symptoms of the fairy ring fungus. The best control of fairy ring is accomplished by reducing the hydrophobicity, so the use of wetting agents to reduce dry spots combined with spiking or coring the greens to improve water infiltration can help. Applying some fast-release nitrogen from a source such as ammonium sulfate [21-0-0] at a rate of 1 g N m^-2 can help to mask the symptoms of the fairy ring. And fungicides with the active ingredients azoxystrobin, flutolanil, triadimefon, polyoxin-D, or pyraclostrobin can control the basidiomycete fungi that cause the fairy ring symptoms.

But overall, zoysia is relatively foolproof in the climate of Southeast Asia, unlike seashore paspalum which is quite suceptible to diseases and dry spots and even death in extreme cases, or bermudagrass which struggles in the low light conditions of the rainy season and is prone to invasion by weeds. Zoysia is a grass you can plant to have a sustainable (low inputs, low cost, good quality) golf course in southern Thailand, and it should be used at more golf facilities throughout the region.

Thatch Control by Burning

This photo is of the shiba-yaki ceremony at Korakuen Garden (後楽園庭園) in Okayama, Japan. I visited this garden in 2008 and wrote about it on the ATC website. This is some of the most beautiful noshiba grass (Zoysia japonica) I have seen, maintained using traditional and simple methods. And one of those traditional maintenance practices is the burning of the dormant grass each winter. This burning improves the quality of the turf in the upcoming growing season. Burning the stems and other organic matter at the surface helps to reduce thatch buildup, creating a firmer surface. Weed seeds are destroyed by the heat of the fire. And burning the dormant turf also creates a natural fertilizer, with the mineral elements from the ash left to nourish the grass as it grows in the spring.

The photo above shows the layer of organic matter that builds up naturally near the surface of a turfgrass stand. This is a ten year old korai (Zoysia matrella) fairway in Western Japan. The organic matter buildup can cause problems with turfgrass quality because of too much water retention in the organic matter and a number of other problems associated with excessive organic matter. Removal of organic matter can be an expensive and time-consuming process; burning the turf when it is dormant is not expensive, but this traditional maintenance practice is not used frequently because of safety regulations. Also, most golf courses remain open during the winter,  and a recently burned turf does not make a good playing surface for the average golfer.

This is the fourth hole at The Cypress Golf Club at Hyogo-ken in early March. The noshiba rough has been recently burned, the creeping bentgrass putting surface is still green through the winter, and there is a dusting of snow on the mountains. Another advantage of burning the turfgrass is the dark color it gives to the ground. This will increase the soil temperatures during the spring and will cause more rapid growth of the grass when it does come out of dormancy.

Now we see the same hole at The Cypress Golf Club in May. The noshiba is growing well, the thatch has been reduced, and weeds are not a problem. The traditional burning of dormant zoysiagrass is not practical at every location, but the importance of organic matter management remains no matter where you are. If you cannot burn the grass, then consider other methods to manage organic matter accumulation: apply optimum amounts of fertilizer, verticut as necessary, dilute the organic matter with sand topdressings.

Turfgrass Research at Mauritius

I was at Mauritius last month and visited most of the golf courses on the island. Mauritius has some of the most visually striking golf courses I have ever seen. I was surprised (and impressed) to see beautiful evaluation plots of grass at Paradis Golf Club, where course superintendent Ajaye Ladsawut is maintaining a nursery with different varieties of bermudagrass, seashore paspalum, and even some zoysiagrass. This is an amazing site for turf research plots, right at the base of a World Heritage Site, the rugged Le Morne Cultural Landscape (see below) which served as a shelter for runaway slaves. The grasses are being grown on two different rootzones, a dark rock sand (foreground above) and a calcareous coral sand (background above); the purpose of the grass evaluation nursery at Paradis Golf Club is to determine which grasses perform the best, and in what soil, for a new course in planning stages now and for possible course improvements at Paradis.

The Paradis Golf Club has seashore paspalum (originally from Durban CC) on the greens, a local bermudagrass is the primary species on tees and fairways, and there are also areas of blue couch (Digitaria didactyla), St. Augustine or Buffalo grass (Stenotaphrum secundatum), Zoysia matrella, and Sporobulus. The irrigation water is rather high in salt as the course sits right on a lagoon, but all these grasses manage to grow well.

The grass evaluation plots at Paradis are very well-maintained and are given nearly the same maintenance treatments as the grass on the golf course. The Bel Ombre paspalum is from a nearby golf course and has a slightly different growth habit and stolon color compared with the Durban CC paspalum on the greens at Paradis.

This is a seashore paspalum fairway (with patches of bermudagrass at right) on Ile aux Cerfs, also at Mauritius. One of the most challenging things in the management of seashore paspalum is to keep other grasses out. The native bermudagrass here is quite salt tolerant and grows vigorously. Rock salt is used here to control most weeds in the seashore paspalum, and the use of salt is a good strategy for weed control in seashore paspalum when soil conditions allow it. Seashore paspalum is beautiful but it can also be a high maintenance grass and will tend to be overtaken by other grasses when grown without intensive and expensive maintenance.

More about Field Day and Seminars

The R&A website now has an update about the Asian Turfgrass Center's research plots, the Sustainable Turfgrass Management seminars held this month, and sustainable golf course management in Southeast Asia.

Field Day Preparations at ATC

We are busy now preparing for the field day on 10 March. New flowers have been placed at the entrance to the research area, soil and water analyses have been conducted, mowing heights and mowing patterns have been adjusted, fertilizers have been applied, and we will be putting out a few more fertilizer trials and wetting agent trials over the next few days.

On 8 March, Steve Isaac from The R&A along with Dr. Doug Soldat and Dr. Jim Kerns from the University of Wisconsin will come by the research area for a preparatory visit prior to the field day on 10 March. At the field day, each of these turfgrass experts will be speaking about their areas of expertise.

The research putting green is now being mowed at 4 mm and the final topdressing (in advance of the field day) was applied this morning.

Beautiful Grass

Two weeks from today, the Sustainable Turfgrass Management for Southeast Asia seminars will commence at Thailand, and there will be a turfgrass field day here at ATC's research area on 10 March. I was out at the research area late Sunday afternoon and then again early this morning, and the grass is growing very well. Even with minimal fertilizer applications in 2009, the grass is growing at a moderate pace and has excellent color.

The putting green we built in November is now mowed almost at putting green height and will be ready for close observation at next month's field day.