This is the last weekly bulletin for the 2007 growing season.
A final summary issue will be published on Friday, November 2 once the fall pest surveys are completed. The authors of the Wisconsin Pest Bulletin would like to express their gratitude to the many cooperators who monitored black light traps, corn earworm flight activity, cabbage loopers, Swede midge traps, western bean cutworm moths, and apple insect pheromone traps this summer. Your contributions of time and expertise have been invaluable to this publication and its readers.
The potential for stalk rot is greater than it has been in several years. This disease is expected to cause stalk lodging in areas subjected to drought stress earlier in the season and high moisture levels this month. Corn harvest could be delayed if plants are lodged or toppled over. Development of stalk rot has been favored by wetter than normal conditions this month, and continued rainy weather could aggravate problems in fall. Losses may be reduced by scheduling an early harvest for fields with the greatest stalk rot potential.
Plants in Dane, Columbia and Dodge County dent corn fields are exhibiting a grayish or pinkish mold growth on the ear tips. It is particularly noticeable where the ear tips are exposed due to insect or blackbird feeding injury. The prevalence and severity are generally light at this time; however, wet weather next month could increase development of this disease. Many ear rot fungi are capable of producing mycotoxins that negatively affect animal health.
There may be some confusion as to the exact extent of rootworm damage in parts of the state due to the influence of weather. Examination of blown down corn stalks in Columbia and Dodge counties failed to reveal any evidence of rootworm feeding injury. Such lodging is likely the result of driving winds, saturated soils, or disease.