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February 2014
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April 2014

March 2014

An update: manilagrass tees and divot problems, or not

Hole 12 at Keya GC, par 3

Last year in March I wrote this post about perceived divot problems on manilagrass (Zoysia matrella) tees. To summarize, I've heard many objections (in theory) to the use of manilagrass on tees in Southeast Asia, the thought being that manilagrass grows slowly and divot recovery may be too slow for this grass to be suitable on tees.

On this topic, it is relevant to consider the approximately 1,800 golf courses in Japan with manilagrass tees. Those tees are played for almost half the year when the grass is dormant. The grass cannot recover from divots at all during that dormant period, yet it still produces an excellent tee surface. If this grass can be used to produce excellent tees when it grows for only half the year, one expects that manilagrass will do just fine on tees in Southeast Asia where it never goes dormant.

Tee at Keya GC Hole 12 in mid-March 2014 after more than 19,000 rounds on dormant manilagrass, photo courtesy of Andrew McDaniel

Manilagrass tees, even on a heavily used par 3, as shown above, still have a lot of grass after an autumn, winter, and spring of play on the dormant turf. Soon after the grass starts growing in April, the tee will be almost 100% grass, with nary a divot to be found.

Muang Kaew GC in Bangkok has about 72,000 rounds every year. During the peak season, 220 golfers play every day. The manilagrass tees never go dormant, nor do they suffer from severe divoting problems.

Manilagrass tee on Par 3 #17 at Muang Kaew GC in Bangkok

There are still divots, of course, but for a course with more than 70,000 rounds a year, to have this type of condition on the most heavily-divotted section of a par 3 tee, tells me that manilagrass grows plenty fast enough to recover from divot damage. Plus, manilagrass is more resistant to divot injury than bermudagrass (Cynodon spp.), and divot recovery times can be just as fast as bermudagrass.

The most-heavily divotted area of the par 3 17th at Muang Kaew GC in Bangkok

 With any grass on tees, especially on busy golf courses, it is important to control the traffic. On seashore paspalum (Paspalum vaginatum) tees at Siam CC near Pattaya, the divots are concentrated on one section of the tee to allow other areas to recover. By starting at the left front of the tee and moving the tee markers back about 50 cm every day, the golfers can always tee off from divot-free grass, and an entire tee of this size can be apportioned into about 42 sections, giving 6 weeks recovery time before returning to a previously-used location. 

Divots on a par 3 tee of seashore paspalum at Siam CC near Pattaya; careful movement of the tee markers gives about 6 weeks recovery time before the same area of the tee will be used again

MLSN article published in Spanish greenkeepers magazine

A new article about the minimum levels for sustainable nutrition (MLSN) guidelines has been published in the January 2014 issue of the Spanish greenkeepers association magazine.

In the article, I wrote about 4 things these guidelines are designed to do:

  1. To ensure the grass is supplied with enough nutrients.
  2. To ensure that excessive amounts of fertilizers are not applied.
  3. To allow for calculation of a sustainability index for each nutrient, comparing the amount of a nutrient in the soil at a site to the distribution of that nutrient in a wide range of turfgrass soils.
  4. To be continually updated and shared as new information is added to the dataset from soils around the world.

The MLSN guidelines are unique among turfgrass nutrient guidelines in that they are explicitly site-specific. By looking at the estimated plant uptake of nutrients for a particular site, comparing that to the amount of nutrients in the soil, and then checking to make sure the amount remaining in the soil will be at or above the MLSN guideline, this approach is a simple, logical, and rigorous approach to understanding turfgrass nutrient requirements.

For more information on the MLSN guidelines, the Global Soil Survey, and turfgrass nutrient requirements, see:

Tea Fans for Air Movement on Bentgrass Greens

I had thought the fans in the tea fields of Shizuoka were used to reduce fungal diseases of the foliage during hot and humid weather. Yesterday I learned that the actual reason for these fans is to prevent frost from forming on the leaves during winter, by blowing warmer air (cold air is heavier, and sinks) down to the plants.

Fan_2006These same fans are used on many golf courses in Japan to improve air movement across creeping bentgrass greens during summer.

The fans are usually painted brown and are kept relatively distant from the green surface, blending right in with the pine trees around the green. These tea fans (o-cha senpuki) are also quiet, and I've been assured by Japanese greenkeepers that they do cause a noticeable improvement in bentgrass greens, without causing too much disturbance to golfers.

Golf in Japan, Mt. Fuji, and the Two Green System

2 bentgrass greens with Mt. Fuji in background

This morning I visited a golf course with a great view of Mt. Fuji. This view will be really stunning in a few days when the cherry trees are blooming.

There are 72 holes (4 courses, each of 18 holes) run out of 1 maintenance facility here, and I was reminded of just how much work is involved in the maintenance of these facilities. Of the 72 holes, 54 of them (3 courses) use the two green system. Only 1 of the courses uses the one green system. And these are not summer and winter greens, they are all creeping bentgrass.

So for 72 holes, there are 126 greens to maintain, plus the practice greens. And this is all done with a maintenance crew of less than 50 people. I'm often impressed at the conditions produced by turfgrass managers the world over, and today I was impressed again.

For more about course maintenance in Japan and the two green system, see:

More photos from the Thai GCSA of Sustainable Turfgrass Management in Asia 2014

Here are three extensive photo galleries with 100s of photos, showing the delegates, speakers, and activities of Sustainable Turfgrass Management in Asia 2014, posted at the Thai Golf Course Superintendent Association page on Facebook

10 to 12 March 2014, part 1

10 to 12 March 2014, part 2

10 to 12 March 2014, part 3

Turfgrass Mystery: can you identify the golf course architect?


For this mystery, I take a slightly different tack, and consider golf course design rather than turfgrass specifically. Each of the three courses shown in this post were designed by the same architect. The hole pictured above is a par 3 on a course in Hokkaido. The hole pictured immediately below is a par 4 on a course in Osaka.


I've noticed a dramatic and distinctive style to the courses designed by this architect. The courses may not be easy to maintain, and may not be easy to play, but they certainly will be memorable, and are some of the most extensively-mounded courses I've seen in Japan.

The final clue is this view across a course by the same architect in Okayama.


This mystery is a simple one. Can you identify the architect of these courses? I expect readers familiar with Japanese golf will know this right away. For those less familiar with golf in Japan, and wanting to do some research on this, I suggest the informative Golf in Japan site.

This was answered correctly, and quickly, by Andrew McDaniel, golf course superintendent at Keya GC. 

 These courses were all designed by Kato Shunsuke. And the photos, from top to bottom, are Hokkaido GC, Hanna CC, and JFE Setonaikai GC. Kato's distinctive design style can be seen at many courses in Japan.

Below I've posted one more photo, this of Kato's Tojo GC in Hyogo prefecture. 


35 Photos from Sustainable Turfgrass Management in Asia 2014 Conference

This year's conference saw 278 people from 20 countries gather in Thailand from 10 to 12 March to learn and share information about turfgrass management. This photo gallery shows a few of the activities at the conference, field day, and turfgrass management exposition.

The 2015 conference will be held on 9 to 11 March 2015. As in previous years, the conference program and venue details will be announced in September. 

The Sustainable Turfgrass Management in Asia 2014 conference was organized by the Thai GCSA and Asian Turfgrass Center for the Thailand Golf Association, with support from The R&A, in conjunction with the AGIF Turfgrass Management Exposition.

Monthly Turfgrass Roundup (February 2014)

In case you missed them, these articles and links from the past month are likely to be of interest to turfgrass managers in Asia:

This conversation about fertilizer

GIS 2014 conference education presentations now available

Growth potential and overseeding 1

Growth potential and overseeding 2

Are the MLSN guidelines for soil nutrients too low?

Turfgrass Twitter Analysis 1

Turfgrass Twitter Analysis 2

Zoysia putting green video

Social media awards and a fun(ny) video

Three new articles in GCM China, and one old video

For more about turfgrass management in Asia, browse the many articles available for download on the ATC Turfgrass Information page, subscribe to this blog by e-mail or with an RSS reader - I use Feedly, or follow @asianturfgrass on Twitter. Link and article roundups from previous months can be seen here.

Relationship between soil moisture and turfgrass surface hardness

Yesterday there was a discussion on Twitter about soil moisture and surface hardness – I use the terms surface hardness and surface firmness interchangeably, but I usually prefer surface hardness.

In the report I prepared in August 2012, I included this figure, showing the relationship I measured between soil moisture (using a Theta-probe with 6 cm rods) and surface hardness (using a 500 g Clegg Impact Soil Tester).


One can't make an accurate prediction of surface hardness from soil moisture in general, because soil types and organic matter content vary, so the surface hardness can be quite variable across a wide range of soil moisture. It does seem that once soil moisture gets above 35% (by volume), it can be difficult to produce a firm surface.

However, for a consistent soil type and species and turf age, there can be a good relationship, as seen below. I'm sure that at many golf courses, there would be a consistent relationship between soil moisture and surface hardness. But that same level of soil moisture may not translate to the same level of surface hardness at another golf course. These data are from a golf course with seashore paspalum everywhere, and with a wall-to-wall sandcap.


Since I prepared the August 2012 report, I've collected another 647 paired measurements of soil moisture and surface hardness, this time measuring soil moisture to a 7.5 cm depth with the TDR-300. These results show a similar result to that measured previously. There is some relationship between soil moisture and surface hardness, but the location effect is important. One really needs to study this relationship at one's site, as Scot Dey is doing, to find how soil moisture influences surface hardness.



The same data (647 measurements collected after August 2012) from the chart above are shown by species in the chart below. 

soil moisture and surface hardness of golf course putting greens

For more about this topic, see: