COURSE CARE
The Rainy Season Has Arrived For Some, But Not All May 22, 2012 By John H. Foy

Unless one makes the more than 10-hour drive from Pensacola in the northwest corner of Florida to Miami in the southern end of the peninsula, few people can appreciate how big Florida really is. It is also human nature to generalize or assume that the exact same weather conditions are being experienced throughout the entire state. As a 27-year resident of Florida, I am still amazed by the diversities and extremes that can occur between the northern, central and southern areas of the state.

This has certainly been the case in recent weeks given the early onset of the summer rainy season in southeastern Florida countered by the continued lack of rainfall throughout the rest of the state. From Palm Beach County and south through Miami, typical summertime thunderstorms have been occurring almost every afternoon and in some locations over 15 inches of rain have been recorded over the past three to four weeks. Throughout the rest of the state, including the lower southwestern coast of Florida, severe to exceptional drought conditions are being experienced according to the National Weather Service’s Drought Monitor as of May 15, 2012.

Hopefully, the summer rainy season and typical afternoon thunderstorms will spread out through the rest of the state and alleviate severe to exceptional drought conditions currently being experienced. With daytime temperatures now regularly hitting the mid-80’s or higher, evapotranspiration (ET) rates are high which leads to increased irrigation needs. This has been especially troublesome for the many courses in central and northern areas of the state that are dealing with water management district mandated restrictions or rapidly dwindling water supplies. Thus, until it does rain, continuing to be proactive with drought management measures is essential. In both of the Florida Regional Updates posted during the month of April, drought management measures were discussed and can be reviewed by clicking on the following links.

http://www.usga.org/course_care/regional_updates/regional_reports/florida/The-Annual-Dry-Season-Is-Upon-Us---April-2012/  

http://www.usga.org/course_care/regional_updates/regional_reports/florida/A-Little-Relief,-But-Still-A-Long-Way-To-Go---April-2012/  

It should be reiterated that both bermudagrasses and seashore paspalum possess good drought tolerance, but with fairways and roughs, restricting cart traffic in the short-term may be necessary to prevent further damage and turf loss.

For golf facilities along the lower southeastern coast of Florida that have received rainfall in recent weeks, other management challenges are being experienced. With bermudagrass, a rapid surge in its growth rate has occurred, thus keeping up with required mowing frequencies so that excessive scalping damage does not occur has been one of the primary challenges. Continuing to closely monitor regionalUpdateContent zone moisture content of putting greens is also needed. With frequent and/or heavy rainfall, the upper regionalUpdateContent zone can remain saturated for an extended period of time, which negatively impacts overall regionalUpdateContent system development and health. When the upper regionalUpdateContent zone remains saturated and it doesn’t rain for even a couple of days, the rapid onset of drought stress can become a problem. This inevitably results in gofers asking questions about why you and your staff are watering the greens when there has been rain nearly every day for the past week.

The other concern that arises with the onset of the rainy season in Florida is the impact of moderate to heavy cloud cover on bermudagrass putting green health and quality. It has been estimated that cloud cover can reduce the daily light integral (DLI) by as much as 45 percent and well below what is considered adequate to support optimum growth. There is no substitute for sunlight, and maintaining an extremely low height of cut will only further compound problems. While it may not be popular because it is harder to provide fast to very fast green speeds, raising the height of cut by at least 0.010 to 0.020 of an inch is strongly encouraged as a survival measure for the rainy season.

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