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The soybean aphid, Aphis glycines (Hemiptera: Aphididae), is the most important insect pest attacking soybeans in North America since 2000. Several studies have documented strong impacts of generalist natural enemies on A. glycines populations using predator exclusion cages and correlating predator and aphid abundances. However, to date no studies directly observed and quantified the natural enemy groups that attack A. glycines in North America under field conditions. In 2005, we conducted 72h of direct observations of predation on natural populations of A. glycines in Michigan. The observations were conducted during three consecutive weeks during morning, afternoon and evening, in replicated 1m² areas. A total of 643 predators within 12 groups and 211 predation events on A. glycines were observed. Transient predators such as Harmonia axyridis and Coccinella septempunctata (Coleoptera …