On July 3rd, Mr. Doederlein went back to the cage and, to his surprise, found large numbers of sugarcane aphids infesting the Johnsongrass that had re-sprouted within the cage. Data from the temperature recorders showed that on the surface there had been 331 hrs with temperatures below 32 degrees fahrenheit. The lowest temperature recorded was 16.3 degrees. The other recorder positioned 2-3 inches below the soil surface recorded 37 hrs of temperatures below 32 degrees fahrenheit and the lowest temperature was 30.07 degrees.
|Sugarcane aphids on Johnsongrass under an overwintering cage. Photo: T. Doederlein|