Early on a Wednesday morning in August, I found Cook County Master Gardeners removing Echinacea plants susceptible to aster yellows. This disease affects over 300 plants in the aster family. It has been wreaking havoc on economic vegetable crops.
Spread by leaf hoppers, this disease is having an impact on the ornamental horticulture industry as well. New cultivars appear to be more susceptible. In plantings like those found in Lurie Gardens, specialty blooms are being removed and replaced with reliable species varieties.