Ground maintenance work for the 1998 season began with spring application of the herbicide Dimension on 23 April at 1.5 quarts per acre, primarily to control annual bluegrass. On 1 May, the wetting agent Cascade was applied at 8 ounces per 1000 square feet, which was followed by the plant growth regulator Primo on 20 May, at the rate of 1 quart per acre. On 26 May, the insecticide carbaryl (Sevin) was applied to fairways and approaches at 2 gallons per acre to inhibit earthworms. At the beginning of summer, the treatment of turf started with 200 pounds per acre of 21-0-21 (N:P:K) (60% UF) on 2 June, followed by 1pint per acre of herbicide Confront, and 2 pints per acre of Trimec Classic on 4 June. A second application of Primo at 1 quart per acre was made on 19 June. There was only one application of fungicide during the entire summer of1998, which was on 25 June with Daconil Ultrex at 3.5 ounces per 1000 square feet. The standard summer field applications of chemicals were concluded with an application of Mach II at 3 quarts per acre on 7 July. [The herbicide Prograss is routinely applied twice each fall for annual bluegrass control at 1 gallon per acre per application. Therefore, the most recent applications were in late September and early November of 1997.] The weather conditions in southeastern Pennsylvania were normal during early summer, with temperatures in the 77 to 84°F range during the day and in the 59 to 66°F range at night. Rainfall was slightly below normal and relative humidity was generally low. A similar weather pattern continued until early August; then, nighttime temperature suddenly rose to 70°F and stayed above 68°F for several days. Although nighttime temperature dropped to 59°F occasionally in August and September, most nights remained warm (>68°F), with frequent rain events and high relative humidity.