Suggestions on the Right Maintenance for the Wrong Grass

Seashore paspalum is a high maintenance grass: to begin with. There is no doubt whatever about that. Frankly, this species is overused (and misused) in Southeast Asia, and thus many golf courses are left with a course requiring more inputs than they are prepared to give. Sure, seashore paspalum can be beautiful, but it is also expensive to maintain, and most golf courses would have better playing conditions for lower cost if they were to use zoysiagrass for fairways and roughs. Let me point out three things about seashore paspalum in Asia that I think everyone should be aware of.

1. Seashore paspalum grows wild in Asia sparingly and only in the wettest areas. However, it is common to find bermudagrass or zoysiagrass growing in all types of environments (sun, shade, wet soils, dry soils) in the wild. Seashore paspalum has been growing in the wild in Asia for well over 100 years but it does not spread except in swamps. There is an excellent paper in Weed Science (Xie et al., 2009) about seashore paspalum and weeds in southern China. The paper is titled "Spatial and Temporal Dynamics of the Weed Community in a Seashore Paspalum Turf" and the researchers set out to measure the spread of weeds through a low-maintenance stand of seashore paspalum at Guangzhou. Weeds were measured every two months during 2007, which was five years after planting, and the turf had not received any herbicides. The somewhat surprising conclusion? I quote: "the seashore paspalum turf has been naturally replaced by manilagrass." Manilagrass is Zoysia matrella. Be aware that seashore paspalum is a grass that will tend to be overtaken by other grasses.

2. Seashore paspalum is pretty, but zoysiagrass is pretty too. And Zoysia matrella has a finer leaf blade than seashore paspalum and is easier to maintain. And some golfers don't like to play from seashore paspalum fairways. Their complaint is that the ball sits too low. Sometimes the seashore paspalum just doesn't want to grow and when that happens the ball sits down a lot more on paspalum than it does on bermuda or zoysia. Here is seashore paspalum at 15 mm and Zoysia matrella at 15 mm. Can you tell which is which? And if you can, is seashore paspalum that much better?

3. My advice for controlling dollar spot on seashore paspalum in Southeast Asia is to increase the growth rate of the grass. On greens and tees, use fungicides as necessary to prevent or control dollar spot. Use a chemical that will control dollar spot, and by all means apply it at the proper rate. On fairways and in roughs, however, it is usually too expensive to apply fungicides to control this disease. Seashore paspalum requires extra care to survive in Southeast Asia or it will be overtaken by zoysia or bermuda. Keep a constant growth rate by applying optimal amounts of nitrogen fertilizer (usually about 3 g N per square meter per month) and maintaining adequate soil moisture. If seashore paspalum growth slows because of inadequate nitrogen or dry soil conditions, it becomes extremely susceptible to dollar spot. Mow frequently with sharp mowers, and that will remove the dollar spot symptoms that do appear.