Golfdom, April 2010

Scott Kincaid left and Dan Walter of Blue Ash Golf Course have put a lot of thought into their fungicide program over the years He uses it every two weeks on fairways and greens Walter also tracks his fungicide use from a contact and systemic approach Contact fungicides control disease by Continued on page 36 tries apt to cause resistance On the other hand Gurke uses the fungicides least prone to resistance most such as chlorothalonil which he says offers strong contact control of several turf diseases Gurke never tank mixes the same systemic products from one spray to the next He also avoids using DMIs from July through mid August They can get a little hot and cause some phytotoxicity he says Gurke also believ es resistance is less apt to occur if fungicides are sprayed at longer intervals Ten applications of the same product will not be at risk of resistance as much as 20 applications If youre spraying every two weeks between applications regardless of conditions youre setting yourself up for resistance more than if youre spraying every three to four weeks he says Walter says chlorothalonil has become the cornerstone of his fungicide program Walter witnessed resistant strains of dollar spot on his courses fairways in 1996 He sprayed propicanizole at the highest rate at three week intervals which led to the resistance Walter then had to eliminate a few fungicides from his rotation At the time Walter also began using chlorothalonil known to offset resistance better than other fungicides the public 36 hole Running Fox Golf Course in Chillicothe Ohio applies propiconazole in spring and alternates chlorothalonil and iprodione throughout the summer A good preventive plan is the best way to control dollar spot in the summer says Jeff Corcoran PHOTOS BY LARRY AYLWARD LEFT COURTESY JEFF CORCORAN RIGHT COURTESY DAN WALTER TOP RIGHT w w w g o l f d o m c o m Golfdom 35 Every now and then dollar spot gets ahead of me so I use a higher rate of what I already use he says Weather is a big factor that determines how Bill Hamilton treats dollar spot which isnt a significant problem for him If Hamilton the superintendent at the 36 hole Silverado Country Club and Resort in Napa Calif sees a couple of patches of dollar spot he looks at the weather report which will determine whether hell apply a fungicide In the past Ive taken a cup cutter and removed dollar spot without applying a fungicide he says Brickley had a problem with anthracnose when he arrived at Bunker Hill 15 years ago He learned what greens were susceptible then removed trees to open up air movement and created programs to combat anthracnose Originally he used thiophante methyl a curative fungicide Then he changed the program to more of a preventive one more of a summer stress program that includes chlorothalonil and fosetyl aluminum Now anthracnose is a secondary disease More than dollar spot or anthracnose Hamiltons main concern diseasewise is snow mold With the wet northern California weather snow mold rears its ugly head regularly Hamilton treats greens and tees only with PCNB pentachloronitrobenzene around Thanksgiving because hes in the process of converting the cool season turf in the fairways to warm season turf Right now snow mold affects the Poa in the fairways but I dont care what happens to the Poa because I want to get rid of it he says The one PCNB application is enough for the year if the winter is fairly dry If the winter is wet Hamilton retreats the greens and tees and with iprodione fludioxonil or polyoxin D zinc salt once a month through March or even into April because the weather still can be cold and damp then Snow mold will do its thing regardless of the turfs health he says Hamilton says he has no problems with summer diseases Hell get Waitea patch in the spring occasionally and take a curative approach We can see it coming because all my guys know how to scout he says On top of that Waitea patch cleans up easily Hamilton says Its more of an aesthetic problem to me he says Walsh is a contributing editor to Golfdom