Final Report - February 7, 2008
The purpose of this trial was to evaluate different timing intervals of fungicide applications necessary to control anthracnose (Colletotrichum cereale) on annual bluegrass fairways. Three products were evaluated combined with and without Daconil Ultrex: Cleary’s 3336, Cleary’s 3336 Plus, and Banner Maxx.
Materials and Methods The trial was initiated on June 18th at Oswego Lake Country Club built in 1926 and located in Lake Oswego, Oregon. Oswego Lake Country Club is a high end Country Club located in the greater Portland area. Subsequent fungicide applications were applied either on a 3 week or 4 week interval. See the application schedule below.
The site was located on the 12th fairway which has a “Cascade silt loam” soil and has been top dressed with sand over the years. The CEC of the soil is 8.9 and the pH is 5.8. This data was taken from a soil sample on June 20th 2006 and analyzed by MDS Harris Labs. The south east quadrant of the fairway has severe slopes ranging from 3 – 8 percent. The course has a history of anthracnose problems.
The fairway was generally 100 feet across allowing for two 50 foot long plots (10 feet wide) abutting each other in the middle. Since plots were sprayed from side to side, a 20 foot strip down the center of the fairway was excluded for rating purposes, because part of this area was over sprayed from the abutting plot.
The products were applied with a walk-over sprayer with a 5 foot boom using a ShurFlo pump powered by 12 volt battery using Greenleaf AirMix nozzles at 30 psi producing a total spray volume of 1 gallon per 1,000 square feet. A walking speed of 3 miles per hour was calibrated using a metronome.
The maintenance standards of this golf course are extremely high. Fairways are mowed 3 to 4 times per week at 0.50 inches using a triplex fairway mower. Wetting Agents (Tricure), growth regulators (Primo,) and fertilizers were applied regularly throughout the trial. Irrigation was applied with a computer controlled irrigation system with supplemental watering done by hand.
Plot quality ratings were made on July 30th, August 13th, August 20th, and September 17th. Since no disease developed, disease ratings were not taken. Data from each rating date were subjected to analysis of variance using a randomized complete block design with 3 replications. Differences between means were determined by LSD at the 5% level.
Trt #Product"Rate (oz/1000)"Interval1Banner1212Banner1283Banner + Daconil Ultrex1 + 3.2214Banner + Daconil Ultrex1 + 3.22853336421633366217333662883336 + Daconil Ultrex6 + 3.22193336 + Daconil Ultrex6 + 3.228103336 Plus421113336 Plus621123336 Plus628133336 Plus + Daconil Ultrex6 + 3.221143336 Plus + Daconil Ultrex6 + 3.228153336 Plus82816Untreatednana
Trt #ProductInterval18-Jun9-Jul16-Jul30-Jul13-Aug20-Aug1Banner21XX X X2Banner28X X X 3Banner + Daconil Ultrex21XX X X4Banner + Daconil Ultrex28X X X 5333621XX X X6333621XX X X7333628X X X 83336 + Daconil Ultrex21XX X X93336 + Daconil Ultrex28X X X 103336 Plus21XX X X113336 Plus21XX X X123336 Plus28X X X 133336 Plus + Daconil Ultrex21XX X X143336 Plus + Daconil Ultrex28X X X 153336 Plus28X X X 16Untreatedna
The summer was unusually mild, and as a result, anthracnose disease symptoms did not develop.
The plot quality was extremely high for much of the trial. During the month of August, the fairway did experience some drought stress and the ratings declined somewhat. However, there were no statistical differences in plot quality. In September, the temperatures cooled off, the drought stress went away, and the plot quality improved. See Table 1.
Table 1: Plot Quality: 1 – 9; 9 = best
Trt #ProductIntervalRates30-Jul13-Aug20-Aug17-Sep 1Banner21187.778 2Banner281876.78 3Banner + Daconil Ultrex211 + 3.286.76.38 4Banner + Daconil Ultrex281 + 3.2876.77.7 5333621486.76.38 63336216877.38 7333628686.778 83336 + Daconil Ultrex216 + 3.287.37.3893336 + Daconil Ultrex286 + 3.2877.38103336 Plus214876.78113336 Plus222.214.171.124123336 Plus28687.77.38133336 Plus + Daconil Ultrex216 + 3.287.37.38143336 Plus + Daconil Ultrex286 + 3.286.76.38153336 Plus28886.37816Untreatednana86.778 LSD @ .05 0.21.81.40.2