Carpetgrass

Of trees, turf, and tropical tournament golf

The Asian Tour is at the East Course of Wack Wack Golf and Country Club this week for the Philippine Open. This photo from pro Yoshinobu Tsukada is the par 3 8th, one of the classic short holes in Asia. One notices a lot of trees, with just a narrow corridor for play.

In a tropical climate, trees and shade can be a desirable feature on the golf course. Shade is certainly welcome, at least from the players' point of view.

Bangsai_umbrellas
Caddies and golfers at Bangsai CC north of Bangkok use umbrellas to provide shade on a sunny summer day

Not all grasses can handle the shade from clouds, combined with the shade from trees. At Wack Wack's East Course, there is manilagrass on the greens, and tropical carpetgrass on fairways and rough. These grasses, tropical carpetgrass (Axonopus compressus) and manilagrass (Zoysia matrella), are the two species that can tolerate low mowing (less than 5 mm) under appreciable tree shade in a tropical climate.

If one wants to have grass, and have trees, then these are the grasses that work. And they require minimal inputs, can be mown as short as one likes, and they can be maintained to the highest level for international tournaments.

These species also work on the local courses that want to have good playing conditions, but may not have an irrigation system, or a big budget. 

Khet_udom_sak
The 1st at Khet Udom Sak GC in Chumporn, Thailand: manilagrass greens, carpetgrass through the green, no fairway irrigation

 And when it rains, these species can handle the tropical rains just fine. But most importantly, they are the species that tolerate low mowing in tree shade in a tropical environment. For more info, see the links immediately below this post.

Pakasai
The 7th at Pakasai CC in Krabi, Thailand: manilagrass greens (3.5 mm), carpetgrass through the green (8 mm on surrounds)

Presentation slides and handout from Malaysia International Golf Symposium 2013

Woods_malaysiaAt this year's Malaysia International Golf Symposium, I spoke about grasses, how they perform, and their nutrient requirements. 

This presentation handout contains additional information and links that supplement the material presented at the symposium.

Click here to download the presentation slides on Nutrient Requirements for Golf Courses in Asia.

Click here to download the presentation slides on Selection of Grass.


Something you don't see everyday: interveinal chlorosis on grass leaves

interveinal chlorosis caused by micronutrient deficiency

Nutrient deficiencies of turfgrass are rare. Macronutrients are usually supplied as fertilizer in amounts that prevent deficiencies, and micronutrients are required in such small amounts that the grass can usually obtain all that are required from the soil, from micronutrients contained in the irrigation water, and from trace amounts contained in various products.

These photos show textbook symptoms of interveinal chlorosis, probably caused by iron deficiency. The leaves have turned yellow, but the veins remain green. This is tropical carpetgrass (Axonopus compressus) grown in sand. The symptoms are especially evident on this grass because of the broad leaves. Click the photos to see a full-screen image.

interveinal chlorosis of Axonopus compressus

The Difference in Leaf Temperature Between Wilting and Transpiring Grass

leaf temperature on a sunny day in May

Today was an especially hot day at Bangkok. I went out for lunch, and when I was driving home I noticed that the thermometer on my dashboard was indicating an outside temperature of 42°C. Upon arriving home, I checked the official temperature, found it to be 38°C, and I promptly went outside with my infrared thermometer to measure the surface temperature of concrete and of grass. See the above image at full size here.

These measurements were made at 14:00. The concrete measured 53.6°C, about 15°C above the air temperature. Manilagrass (Zoysia matrella) wilting in the sun had a similar temperature, 48.8°C, more than 10°C above the air temperature. Meanwhile, manilagrass and carpetgrass (Axonopus compressus) in the same lawn, in areas with adequate water so the grass could transpire, had leaf temperatures ranging from 1.8°C below to 1.2°C above the ambient air temperature.

As part of a putting green performance data research project, I've collected leaf temperature data from hundreds of greens across multiple grass species in many countries. As of today, I've measured the surface temperature 802 times. If you are interested in reading more, these data are summarized beginning on page 21 of this report. It has been my observation that in conditions of full sun, minimal wind, and adequate plant water status, meaning the grass leaves are not wilting, no matter how hight the ambient air temperature, the leaf temperature will generally be within 1°C or 2°C of the air temperature. Have you ever measured anything different?

For those more familiar with °F than °C:

38°C = 100.4°F

53.6°C = 128.5°F


Shade and the Performance of Warm Season Grasses in Asia

Have a look at this image. It is an aerial view of Wack Wack Golf and Country Club, a 36 hole golf course in Manila. The West Course is on the left side of the image, and the East Course is on the right side. Do you notice a difference in the grasses?

To me, the grass on the East Course looks greener and healthier than the grass on the West Course. And the grasses are different. The East Course has broadleaf carpetgrass (Axonopus compressus) fairways and manilagrass (Zoysia matrella) greens; the West Course is all hybrid bermudagrass.

Trees on the East Course (see below) throw shade everywhere, but the carpetgrass and manilagrass still thrive in these conditions. The bermudagrass does not.

Shade_wack_wack_east
This case study on The R&A's Golf Course Management site provides more details and photos about the benefits of using native grasses at Wack Wack. The aerial view shows just how well those native grasses perform in that environment.

Just down the road at Manila Golf Club, there is some incredible shade thrown across the course each morning by a row of 55 story buildings on the east side of the property.
Shade-mgc
In such heavily shaded conditions, manilagrass performs the best, then seashore paspalum, with bermudagrass (Cynodon) not doing well at all. In the photo below, I identify the manilagrass with my nose, and the bermudagrass test plots identify themselves - they are basically dead. 
Planking_shade
In tree shade or in building shade in Southeast Asia, manilagrass performs exceptionally well as a fine turfgrass. But there is another type of shade, one that can block up to 75% of photosynthetically active radiation. That is the shade that comes from clouds. 

498_micromolesLast week, I took this photo at 10:51 in the morning. The sun was behind a cloud and the quantum meter has a reading of 498 micromoles of photosynthetically active light per square meter per second. That is less than 25% of full sunlight. The effect of clouds is not terribly important for cool-season grasses, and most textbooks ignore it, but this is a big issue for warm-season grasses.

I've studied and written about this and its relevance particularly to the conditions so common in East and Southeast Asia.

From Indonesia in the south to Japan in the north, we see that manilagrass, and in the areas with average annual temperature above 22°C, carpetgrass as well, perform extremely well. Particularly in shaded conditions, which can be caused by trees, buildings, or clouds, these grasses outperform bermudagrass and seashore paspalum. 

My View About Grass Selection on new Golf Course Management website

Golf_course_management_randa-1The R&A have put together a new website rich in information about golf course management. The site, appropriately, is titled Golf Course Management: information, resources, and tools.

In the My View section I've written about grass selection for greens and fairways in Asia. My view is that when it comes to putting greens, because they occupy such a small area of the course and no matter which grass is chosen the greens will always receive intensive maintenance, a high maintenance grass is often the right choice. And my view for fairway turf, because fairways occupy such a large area of the course, is that it is best to choose a grass that won't die. When the grass won't die, then turfgrass managers are able to modify the playing conditions to create almost any type of surface. In Southeast Asia, these grasses that don't die are manilagrass (Zoysia matrella) and broadleaf carpetgrass (Axonopus compressus).

Golf_course_management_randa
The site is packed with information including My View pieces by other golf course specialists, case studies, including those of courses that have used just those grasses. Read about Thailand's award-winning Banyan Golf Club with its manilagrass fairways and the amazing East Course at Wack Wack Golf and Country Club in Manila. This course, with carpetgrass fairways, was just selected as the best course in the Philippines.

There is also the Course Tracker, a new tool to monitor, analyse, and report on your course, and the introduction of the Holing Out Test for assessing putting surface reliability. In the video below, I demonstrate the Holing Out Test on creeping bentgrass putting greens in Japan.


Turfgrass Mystery: what grass is this?

You may be surprised at the answer. What grass is referred to here? From an article by Charles Vancouver Piper, first chairman of the USGA Green Section:

"________ is the best of all grasses in the South for fairways. It makes a dense, uniform turf even on pure sands and the leaves are stiff enough so that the ball is always well off the ground. The only other grass to compete with it is Bermuda; but under conditions where both will grow, _________ makes far superior turf."

Please leave a comment here or reply on twitter with the answer. I'll post the answer and some descriptive photos in a few days. And here it is:

green fairway of Laguna Phuket

The grass Piper was referring to is broadleaf carpetgrass, Axonopus compressus. Read the article here, from the December 1921 issue of the Green Section Record. Thanks to Captain Ben Sims, Jason Chennault, Jim Prusa, Scott McVey, and John Dempsey who all gave the answer of carpetgrass or the genus Axonopus. At right, the beautiful carpetgrass fairways of Laguna National Golf Club in Phuket.

Other guesses pretty much covered the spectrum of warm-season grasses used on fairways: kikuyugrass, buffalograss, St. Augustinegrass, seashore paspalum, bahiagrass, centipedegrass, and zoysiagrass. 

Carpetgrass was a bit of a surprise to be mentioned in this way, and I received a lot of comments from people who said they don't like the grass. Perhaps in an area with a lot of sunshine, and a relatively high maintenance budget, bermudagrass would be a better choice. But there are a lot of areas in the world where carpetgrass thrives and provides the type of playing surface that no other grass can. Just yesterday, I played the famous course at Nuwara Eliya, on stunning carpetgrass fairways (note that these are Axonopus affinis, similar but not the same species as referenced by Piper). See below. 

At this course, the fairways are pesticide free. Weed-free too, except for a few other naturalized grasses that come in. And in the salubrious climate of Nuwara Eliya, the fairways are mown less than five times a month.

Carpetgrass

For more information, have a look at this photo gallery, read this article about Manila's Wack Wack Golf and Country Club, and see this article I wrote about C.V. Piper, who made the stunning statement about carpetgrass in the first place!