by Olivia Huang, Professional Golf Management major
Some golf course managers have gotten severe headaches from a visible “coin” located on golf greens.
Unfortunately, those “coins” are worth nothing, instead, they are dead turfgrass causing by disease. Because the dead turf size is about the size of a silver dollar, we call it Dollar Spot, as shown in the photo.
Dollar spot is a foliar disease of furfgrass caused by a pathogen classified as Sclerotinia homeocarpa. Affected grasses will show symptoms as “white to straw-colored lesion that progress downward from the leaf tip or laterally across leaf blade,” (Tom W. Allen, Alfredo Martinez, and Lee L. Burpee). Individual leaf blades can be damaged in many forms: 1, many small lesions,2, one large lesion, or 3, the whole leaf bale can be blighted. If a small part of the grass has been affected, it might “coalesce into large straw-colored areas of blighted turf measuring 15cm -3 meters in diameter” (Tom W. Allen ). Turfgrasses that are affected by dollar spot disease often have thinned foliage and may be intruded by weed species, and golf course managers will be worried if that happens (especially on putting greens).
The environmental effects of dollar spot disease are: 1) it is toxic for the root of plants and hard to cure, 2) it will widely spread out as it develops, 3) the fungus can be easily carried by equipment (eg: golf clubs), water, living species, and wind aids.
But don’t worry, scientists have figured out some ways to manage this type of disease:
1. Maintaining soil moisture (low soil moisture helps developing dollar spot)
2. Keep monitoring fertility (low nitrogen fertility is beneficial to infection from the disease)
3. Fungicides such as benzimidazole and nitriles are effective
4. Biological control
(Remember: “Perhaps too much of everything is as bad as too little” –Edna Ferber)
The golf course is a territory where managers need to deal with turf every single day, and if they don’t, the diseases like “dollar spot” might invade the whole course and decrease the quality of the course. Therefore, it is important to be able to forecast and prevent turfgrass diseases.
Allen, Tom W., Alfredo Martinez, and Lee L. Burpee. “Dollar Spot of Turfgrass.” www.apsnet.org. N.p., 2005. Web.
“Dollar Spot (Center for Turfgrass Science).” Center for Turfgrass Science (Penn State University). N.p., n.d. Web. 22 Jan. 2016.
Photo credit: P. Vincelli
This blog post was an assignment for Societal Issues: Pesticides, Alternatives and the Environment (PLNTPTH 4597). The views expressed are those of the author and do not necessarily reflect the views of the class, Department of Plant Pathology or the instructor.