In the southern United States, most areas fall under the humid subtropical umbrella. That means sweltering temperatures and a near-year-round growing season. Rodney Crouse and William Brooks, both prior superintendents, share the characteristics of these courses, the challenges they face, and how superintendents overcome them.

It’s More Than Bermudagrass

While bermudagrass is the most commonly used warm-season species, zoysiagrass is quite common, too. Zoysiagrass is often chosen for fairways because of its stiffer leaf blade, which stands more upright than bermudagrass. This results in a perching effect; the ball will sit as though it’s on a tee, which golfers appreciate. It’s also chosen for areas with lots of tree cover due to its shade tolerance, which is not an attribute of bermudagrass. Seashore paspalum is often used for greens in coastal areas, especially in Florida. This is because courses next to the ocean deal with a lot of saltwater in the air, and seashore paspalum tolerates it very well.

Growth Spurts

When the heat hits, around May into June, the high temperatures and sunny conditions make warm-season grass take off like a rocket. For the most part, superintendents will be mowing year-round, but the main active growing season is from April through October. Once soil temperatures get below 60-70°F and the days get shorter, there won’t be as much growth.

Dealing With Disease Pressure

Since it’s hot and humid for most of the season, that translates to constant disease pressure. The dog days of summer are from June through August, which is when we’ll see 90-100°F temperatures and 80-90% humidity. This is amplified during hurricane season due to tropical pattern shifts coming off the water. Our customers with bermudagrass are spraying preventative fungicides at least every 14 days to stay ahead of take-all root rot, mini ring, and patch diseases.

Armyworms and Mole Crickets

Mole cricket control is relatively straightforward; fipronil is the most common choice. Superintendents will start to treat them in June, and depending on the level of pressure, they may have to treat them all summer. Then, the armyworms arrive.

For armyworms, they’ll use bifenthrin, Triple Crown, and Acelepryn during the July, August, and September timeframe. Armyworms blow in on tropical storms, and pressure varies from year to year. This year hasn’t been too bad for pressure, but last year, armyworms were destroying courses. It’s important to expect the unexpected and make that preventative application.

Weed Control

When it cools off in the winter, it stays warm enough for weed seeds to stay viable. Our customers will typically do three to four pre-emergent applications during the off-season. They’ll also use post-emergents when the grass is dormant to kill any weeds that pop up, like Poa annua. Courses up north often maintain Poa, but in the South, it invades greens, shortcut grass, and dormant bermudagrass.

Dealing With Leaching

Leaching is a big issue because when it rains, it’s typically quite heavy; one to two inches in an hour is commonplace. When that happens, a lot of nutrient leaching occurs. It’s common to use foliar sprays every seven days during the season. Superintendents will also use a lot of plant growth regulators (PGRs) because bermudagrass often becomes ‘puffy,’ and reel mowers can defoliate the plant in those areas.

Thatch Management

Too much organic matter will cause warm-season grass to choke itself out. Cultural practices are the key here. A common schedule is verticutting once per week, lightly topdressing with fine sand once per week, and going out and needle tining greens to open them up for gas and air exchange.

Overseeding

Some superintendents overseed fairways and tees because we are in a tourist climate. Some choose to overseed their greens, but we often advise against that because the transition when the cool-season grass dies can be a bit unsightly. We often recommend painting to avoid competition between grasses while still maintaining a healthy appearance.

Dormancy and Speed

Bermudagrass will go completely dormant during the off-season (January through March). Since there’s no growth, there’s no leaf blade to slow balls down, which means green speeds increase drastically. When the grass is coming out of dormancy, superintendents need to use the right mix of PGRs and roll frequently since green speeds will go down quickly as growth begins again. You can go from rolling a 12 or 13 to rolling an eight or a nine within a couple of weeks, which will likely result in complaints.

All About Irrigation

This is a “depends on where you’re at” factor. If you’re on a sand-based golf course, you can experience heavy rainfall and then have localized dry spot in two or three days because it dries out so quickly. The pore space is so big in the soil profile that the water just runs through it. For instance, last year, we had a storm that brought 24 inches of rain in 12 hours. It washed out roads and bridges, but it didn’t rain again for 10 days. Seven days into that dry period, we saw grass start to brown up because the sand takes the water and sends it through the soil profile.

For courses with more clay-like or loamy soil profile, it’s a completely different story. We have courses that are right beside each other, and one may have localized dry spot on their greens and ask for a wetting agent that will hold water, while another will say their course is wet and that when they irrigate, it won’t drain. Each course is its own microclimate, and within that microclimate are even more microclimates.

In coastal South Carolina, superintendents frequently deal with bad water, high salt, high bicarbonates, and high pH. This leads to fertilizer not working as well and increased disease pressure. Additional inputs of calcium and gypsum can move the salt out of the soil. Customers often opt for more sulfur-based fertilizers in the spring and fall when it isn’t too hot, which will lower pH levels.

Common Mistakes

Pre-emergent selection and pre-emergent timing are the two easiest things to make mistakes with. Much of this has to do with the weather and how hard it is to predict. Sometimes, superintendents will go out too early or too late because they were waiting on a certain set of weather data that they thought would be compatible. Sometimes, there will also be an overlap of products on greens, and if the rate is over the yearly maximum, it can kill the greens.

Some Advice

  • Personally, we’d say you need to be more preventative than curative down here when it comes to herbicides, fungicides, and insecticides. 
  • It’s also important to develop a good PGR plan right off the bat, and you’ll probably need to experiment with rates since many of our customers use a different rate for the same product; this goes back to the microclimate point that every course is different. 
  • For fertilization, superintendents will use a slow-release fertilizer a couple of times per year on their fairways between March and October. Nobody sprays fairways down here that we know of. 
  • As far as greens programs go, do a soil test and see what you need. Most greens need calcium down here due to the sandy soil, so keep that in mind.
  • Preparing for hurricanes is also very important if you’re on the coast. It’s important to get pre-emergents out early or as quickly as possible so the hurricane doesn’t wash away your application. 
  • A safety and preparedness plan for hurricanes is also important to protect your property, staff, and guests.

Down south, course management is a constant revolving door. There’s very little (if any) downtime, so it’s important to make the most of your budget and the time you do have. Talk to people at courses near you about strategy, and reach out to your ATS rep for tips and advice.

This blog was co-authored by Rodney Crouse and William Brooks, both ATS reps and prior superintendents