Growers in Michigan have recently been reporting the presence of spotted black aphids on their chrysanthemum crops. These black aphids, Macrosiphoniella sanborni, are chrysanthemum aphids.
As their name implies, chrysanthemums are the only known hosts in North America. This species of aphid is darker than all of the most common aphids. The winged adults are 2 to 2.5 millimeters long.
Growers interested in identifying the aphid on their crop should not do so solely based on color, as the color of aphids can be affected by factors including symbiotic bacteria and their food source.
Michigan State University’s Heidi Wollaeger recently offered tips on how to identify and manage chrysanthemum aphids. Wollaeger’s report includes the best materials to use, as well as input from Extension experts in other parts of the U.S.