The efficacy of repeated fungicide applications, fungicide programs, and a kelp treatment were determined for control of anthracnose on an 80% annual bluegrass/20% creeping bentgrass putting green. The trial was initiated 23 Jun and biweekly applications were made through 01 Sep. The study was conducted at Eugene Country Club in Eugene, Oregon on a nursery green built in the fall of 2007 using aerification plugs taken from the golf course and placed on top of 6 inches USGA sand over soil. The size ofthe plots measured 5 ft × 5 ft. Fungicide treatments were applied with a CO2-powered sprayer with a 5-ft boom and TeeJet 80015 nozzles delivering a spray volume of 2 gal per 1000 sq ft at 30 psi. Plots were walk-mowed daily at 0.105 in. A soluble fertilizer was applied the first week of Jul and a second was applied the first week of Aug at a rate of 0.25 lb N and 0.30 lb N/1000 sq ft, respectively. Irrigation was applied using a RainBird irrigation system at 80 percent of ET with dry spots being handwatered when necessary to avoid drought stress. Moderate drought stress did occur in early Jun as a result of a power outage to the irrigation controller. Foliar symptoms began to develop the third week of Jul and Colletotrichum cereale was confirmed asthe causal agent by the Oregon State University Disease Lab. Turf quality and disease ratings were taken throughout the trial, however, only percent anthracnose ratings taken on 21 Jul (early infection) and 25 Aug 09 (peak infection) are presented. Turfquality ratings were made on a 1 to 9 scale (9=best quality). Data was subjected to analysis of variance using a randomized complete block design with 3 replications. Differences between means were determined by Fisher’s LSD at the 5 percent level.
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