Dollar Spot: How Did It Get Here and How To Prevent It
July 1, 2021 10:09 AM
Dollar Spot: How Did It Get Here and How To Prevent It
What are the circular spots showing up on your turf? It could be dollar spot. Golf course superintendents understand the challenge of preventing dollar spot on the course. Through the continuous monitoring of a course’s conditions, you can avoid environments that encourage dollar spot growth.
What is Dollar Spot?
Dollar spot is a fungus that appears first as small, yellow spots on individual grass blades and then as sunken, tan spots the size of a silver dollar. It affects most warm and cold-season grasses, especially bluegrasses and bentgrasses. Turfgrasses that are deficient in nutrients are more susceptible to dollar spot formation.
Dollar spot forms in high humidity and high temperatures when lots of moisture is held on the grass leaves. It forms from late-spring to late-fall, especially after extremely moist weather or after warmer days with cooler nights. It is spread to other parts of the turf through leaf tissue and clippings from the infected areas. Anything from mowers, golf carts or golf shoes can spread the fungus to other areas of turfgrass.
Leaving grass wet for long periods of time aides the formation of dollar spot. This includes overwatering the turf or late-day irrigation. Mowing grass too closely can also lead to dollar spot, because short grass holds more moisture on its leaves.
How can Dollar Spot be Prevented?
Dollar spot is encouraged when there is moisture on the grass leaves, so it is important to have proper irrigation timing and irrigate based on soil moisture, not based on a set schedule. Irrigation periods between midnight and 6 a.m. limits leaf wetness. Understanding soil moisture is key to preventing dollar spot on your turf. Soil that is too moist will promote the growth of dollar spot, so keeping soil moisture to the correct level will prevent dollar spot.
Mowing grass higher prevents dollar spot since longer grass holds less moisture. Mowing in the morning to remove excess dew can prevent dollar spot but be careful because it can spread dollar spot if it is already active in the area. It is important to reduce humidity and improve air movement near the turf to limit the conditions for dollar spot formation. Proper nitrogen fertilizing will reduce the occurrence of dollar spot.
Technology to Monitor Soil Moisture Levels
Using a soil moisture meter, like Spectrum® Technologies’ line of
FieldScoutTM TDR meters, gives a quick and accurate reading of the current condition of the
soil.
FieldScoutTM TDR 350 Soil Moisture Meter shows soil moisture levels in less than a second. It logs up to 50,000 past measurements, which can help create an irrigation schedule based on moisture levels. It also measures turf surface level temperature and electrical conductivity. The TDR 350 allows you to easily analyze objective soil measurement data to verify cultural practices.
Spectrum® Technologies also offers a series of
WatchDogTM WaterScout Irrigation Stations that can be used to prevent dollar spot. These irrigation stations have multiple sensors to monitor soil moisture and temperature. The irrigation stations allow for remote access to monitor current conditions of the turf at any time. Monitoring soil moisture and temperature prevents the chance of dollar spot forming on the turf.
Back