Viridescent - the Asian Turfgrass Center blog

Research, Teaching, and Speaking in Tennessee

I visited Tennessee this month, speaking at the packed Tennessee Turfgrass Association conference, meeting with faculty in the Plant Sciences Department at the University of Tennessee (of which I am an adjunct faculty member), learning about some of the turfgrass research projects now underway at the University, and teaching this semester's first session of the Turfgrass Rootzone Construction and Management course.

I participated in a panel discussion with Rodney Lingle (Memphis CC), Matt Shaffer (Merion Golf Club), and Chris Hartwiger (USGA Green Section) in which we discussed ultradwarf bermudagrass management, preparation for the 2013 US Open, cold tolerance of bermudagrass, and heat tolerance of creeping bentgrass. I gave three other presentations at the conference, on topics ranging from course preparations for the Open Championship, fertilizer for sand rootzones, and turfgrass management in Asia. The attendance at the conference was superb. In fact, for many of the presentations it was standing room only, and the trade show was bigger than I had expected too.

At the University of Tennessee I saw the now completed Center for Athletic Field Safety with some really great looking synthetic surfaces along with natural turf. This impressive facility is being used for some cutting-edge research about sporting surfaces, biomechanics, and athlete safety.

I saw a lot of other research as well -- zoysia trials, lots of weed control work, many with the new herbicide indaziflam, rooting experiments, seedhead control of zoysia -- suffice it to say that there is a lot of interesting information being developed by the turfgrass team at the University of Tennessee.

We also discussed turfgrass educational programs in Asia and weed control in India for upcoming sessions of the Indian Golf Union's Greenkeeper Education Programme.

At the end of my week in Tennessee, I taught the Plant Science 442 course, Turfgrass Rootzone Construction and Management. I talked about sand rootzones, why we do core aerification (coring, hollow-tine aerification), and what some of the challenges are in managing turf in sand rootzones. I spoke, basically, about these topics:

• Managing the rootzone (handout from Sustainable Turfgrass Management in Asia 2010)
• Managing the rootzone (presentation slides from Sustainable Turfgrass Management in Asia 2010)
• Do fairways need a sandcap? (article from Asian Golf Business)

Chemical Fertilizer Programs for Sand Based Rootzones - the 1 minute version

Last week at the Tennessee Turfgrass Association conference I gave a 30 minute presentation with the title Chemical Fertilizer Programs for Sand Based Rootzones. But this topic doesn't always require 30 minutes to explain - I like to distill this topic into the most important principles. There is plenty of experimental and empirical evidence to show that these four principles, if followed, will give excellent results.

1. Apply the right amount of nitrogen
2. Ensure soil pH is more than 5.5 and less than 8.3
3. Ensure soil potassium (as measured by the Mehlich 3 extractant) is kept above 50 ppm
4. Ensure soil phosphorus (as measured by the Mehlich 3 extractant) is kept above 35 ppm

The End (of the 1 minute version of this topic)

If you are especially interested in mineral nutrition for turfgrass or soil nutrient analysis for sand rootzones, you may want to read or watch some of these more lengthy expositions.

Simple Fertilization: Use the Nutrients Already in the Soil, from the Hawaii GCSA newsletter

PACE Turf Potassium Sufficiency Video, on Youtube

Soil Testing: It Does Not Have to be Difficult, on Youtube

Creating an Excellent Playing Surface: Managing the Plant, especially section 2 regarding nitrogen application

Does Potassium Fertilizer Really Increase Roots?, from TurfNet Monthly

And for those who really want to reduce P and K, consider the implications of The Park Grass Experiment and the Fight Against Dogma, written with Dr. Frank Rossi and published in the USGA Green Section Record

Potassium for Turfgrass: interview with Dr. Larry Stowell of PACE Turf

Dr. Larry Stowell and I recorded this video interview about potassium fertilizer for turfgrass. How much potassium is enough? How should you decide how much potassium to apply to meet the plant requirements, without wasting money by applying too much? Is potassium fertilizer necessary at all? Watch this video to find out, and check out PACE Turf for a wealth of valuable turfgrass information.

Cynodon, Paspalum, and Zoysia at Putting Green Height

Golf course putting greens in Southeast Asia are usually planted to either hybrid bermudagrass (Cynodon dactylon x C. transvaalensis), seashore paspalum (Paspalum vaginatum), or zoysia (Z. matrella or Z. pacifica). I saw this test recently at a golf course in Southeast Asia. This is a putting green in an area with extensive cloud cover for much of the year. Can you identify the species being grown here? Which are bermuda, which are paspalum, and which are zoysia?

This green is being maintained at about 4 mm, the test plots have been established for more than three months, and there are obviously some differences in how the grasses perform at this mowing height. This test corresponds exactly with what I have observed on the performance of these grass species at low mowing heights across a broad swath of Asia.

World Cities Plotted by Climatological Normals, January

This chart shows a selction of world cities, plotted by average temperature, sunshine, and precipitation for the month of January. Bangkok, Chennai, Colombo, and Mumbai look like splendid places this month, at least for the growth of warm-season grasses. It will normally be warm, sunny, and dry in these cities, allowing turfgrass managers to control the growth with fertilizer and water applications, without concern for a lack of sunshine. 

World Cities Plotted by Annual Climatological Normals

On these charts, a selection of world cities are plotted according to their average annual temperature and average annual sunshine hours, with the size of the bubble for each city proportional to the average annual precipitation. The display of information in this way allows us to identify quickly some differences between the normal climate in different locations. Miami and Honololu, for instance, are very similar in average annual temperature, and almost the same in sunshine, but Miami has much more rainfall than Honolulu. 

The charts are shown with the x and y axes going to zero in the plot above, to get some sense of the range of variation in the data, and in the chart below the data are plotted to fit the chart, so that we can more easily identify the location of the cities. Atlanta has a similar annual temperature to Osaka, and similar precipitation, but there are about 40% more sunshine hours in Atlanta each year than in Osaka. That difference is clearly something to consider if we think about how, for example, ultradwarf bermudagrass greens would perform, or should be managed, in those different locations. 

Photosynthesis is affected by temperature, light, water availability, and leaf nitrogen content. Turfgrass managers control the nitrogen by judicious application of fertilizer, and the water availability is controlled partly through precipitation and partly through supplemental irrigation. Light and temperature, then, stand out as the uncontrollable influences on photosynthesis. In the warm-season areas of the United States, there tends to be relatively high sunshine. It is normal to have 2500, 3000, or even 3500 sunshine hours in a year. So in the United States, much of the grass selection, when it comes to warm-season (C₄) grasses, is just a matter of temperature -- "is this a warm-season area, by temperature, or not?" 

In Asia, there tends to be less sunshine. If we compare Hong Kong with Miami, we see that Miami is slightly warmer, and Hong Kong has a bit more precipitation, but there is a huge difference in sunshine hours, with Miami having on average about 70% more sunshine hours than at Hong Kong. Does this have an affect on turfgrass performance? Yes! We see Zoysia matrella thriving in Hong Kong, and Singapore, and Tokyo, all cities where the sunshine hours are relatively low. Bermudagrass, on the other hand, performs relatively poorly in these same cities, and requires special care to keep in a playable condition. 

ATC in 2011, by the Numbers

As we come to the end of another year, it is interesting to look at some of the numbers related to the work done this year, particularly in comparison with the previous years (2009 report, 2010 report). In 2011, I'm especially glad to see that we continue to provide more people with turfgrass information through our websites and training programs.

• Visitors from 119 countries visited this website, Viridescent, for which I wrote 60 new posts in 2011. Both are a substantial increase over 2010, and we saw a 22% increase this year in unique visitors to the Asian Turfgrass Center, Asian Turf Seminar, and Viridescent websites.
• Volume of soil and water analyses for select clients in Asia were up by 70% this year as turfgrass managers see the value in a scientific approach to plant nutrition.

• I made about 35 presentations at universities, educational conferences, and golf course superintendent meetings at Japan, Australia, China, Thailand, India, United States, and the Philippines. The highlights include keynote talks about plant nutrition at the Australian Turfgrass Conference in Adelaide in June and conducting the India Greenkeeper Education Programme at Kolkata, New Delhi, Mumbai, and Bangalore in November and December.
• My work took me to fifteen countries in 2011.
• I flew 94 times, an average of one flight every 3.9 days.
• Fourteen articles were published in 2011 including the cover story from the January Greenkeeper International and the story I wrote with Dr. Frank Rossi about the endlessly fascinating Park Grass experiment, published in April by the USGA Green Section Record.
• I made ten posts at the Turf Diseases website - newly redesigned this year - for which I am an occasional contributor on international topics.
• Visitors to the Asian Turfgrass Center website were from 70 countries and the top ten countries sending visits were, in this order: Japan, United States, Thailand, Australia, Malaysia, India, United Kingdom, Singapore, Philippines, and China.
• I made nine interactive bubble charts of climatological data and fourteen static charts; these data graphics are useful in predicting which grasses will perform well in specific geographic regions and in preparing maintenance calendars for different grass types.
• Data were collected from 220 putting greens in six countries growing seven species of grass. This ongoing project characterizes the playing performance of different grass species and establishes normal values for different grass species in Asia. 
• This year ends, as did 2010, with plans for a number of upcoming seminars, advisory work for great clients, travel to salubrious places, and a long list of exciting writing projects.

Registration Now Open for Sustainable Turfgrass Management in Asia 2012

Registration is now available for the Sustainable Turfgrass Management in Asia 2012 conference. Dr. Doug Karcher from the University of Arkansas will be speaking about soil moisture management, wetting agents, evaluating shade problems, and grass variety differences; Dr. Lane Tredway from North Carolina State University will teach about advanced management of turfgrass diseases, and there will be other presentations about turfgrass management in Asia from the Thai GCSA. The registration fee for this three day conference includes two days of classroom seminars at the 5-star Amari Orchid Pattaya, the Asian Turfgrass Field Day, two conference dinners, three lunches, and a printed copy of the conference proceedings. Hotel reservations should be made directly with the conference hotels.

Download the registration form in Thai (ภาษาไทย) 

Download the registration form in English

Why "Liquid" Fertilization is Better Terminology than "Foliar" Fertilization

When applying fertilizer to turfgrass plants, there are two general types of application: liquid and granular. Granular products are applied in a dry form, while liquid products are applied as a spray application.

The term foliar fertilization is often used to describe liquid applications made to the leaves, or foliage, of turfgrass. But this can be misleading,with the implication that all the applied fertilizer is being taken up by the foliage. 

The reality is that only about 50% of the fertilizer applied to turfgrass foliage enters the plant through the leaves. And in many cases much less than 50% is absorbed by the leaves. Recent research by Branham et al. found that 14 to 37% of the applied nitrogen was taken up by turfgrass leaves in Illinois. Research at Arkansas by Stiegler et al. found uptake of 36 to 69% of foliar-applied nitrogen. These results are similar to the experimental results of Professor Jörg Schönherr who has done extensive research into foliar uptake of nutrient ions. Uptake is the highest at 100% humidity, so once the liquid solution has dried on the leaf, foliar uptake of the applied nutrients ceases. 

Even with the limited foliar uptake, I still prefer liquid applications to granular applications. With liquid applications, precise doses of nutrients can be spread evenly at low rates to all areas of the sward. It is impossible to get such even distribution of nutrients when applying granular products. 

When I was the superintendent at Shanghai Links, we made liquid fertilizer applications to all areas of the course as the main source of nutrients. We would allow the fertilizer to dry on the leaves, so we would get some uptake by the foliage, and we would then apply enough water to rinse the remaining fertilizer from the leaves and into the upper reaches of the soil, where the remaining nutrients could be absorbed by the roots.  

How to Prepare an Elephant Polo Ground

When you want to play elephant polo, you surely think of having a well-prepared field. But just six weeks before this year's King's Cup Elephant Polo Tournament, the field needed a lot of work. Minachai Srichanya, the golf course superintendent at nearby Banyan Golf Club, coordinated a volunteer maintenance program to turn the field from this ...

... into this.

What work was done to get such an improvement on this field, situated at an army camp just south of Hua Hin? First, the edge of the field was marked, the grasses (primarily Zoysia matrella) and weeds were mown, and clippings were removed. This work was done by the golf course maintenance staff from Banyan Golf Club, with support from Jebsen & Jessen and The Toro Co.

Then, fertilizer was spread to stimulate grass growth, and sand topdressing was applied where necessary to smooth the surface.

Then it was just a matter of more mowing, and time, to produce the results for this hotly contested international polo tournament. No word yet on how much soil compaction is caused by polo elephants. More than from ponies, one presumes. 

Photos provided thanks to Banyan Golf Club and the Kings Cup Elephant Polo Tournament.