Issue 5, May 23, 2011
Vanhoutte spirea is still in bloom in central and northern Illinois, so refer to the scouting watch particularly for insects that are susceptible to control as bloom ends or finishes. This spirea bloom was extended this year due to the below normal temperatures experienced in Illinois over the last two weeks.
Several borers are susceptible to control at this time throughout the state including flatheaded appletree borer, roundheaded appletree borer, viburnum crown borer, and peachtree borer. Lilac (ash) borer and bronze birch borer are still susceptible to control in central and northern Illinois.
Several scale insects are in the crawler stage and susceptible to control. In southern Illinois, euonymus scale is susceptible to control. In central and northern Illinois, Fletcher scale, pine needle scale, and both gray and brown oystershell scale are susceptible to control. (Phil Nixon)