2.5. Field cage experiment
To determine how the intraguild interactions examined in the microcosm experiment compared with interactions in the field, where a larger complex of generalist predators was present, a field cage experiment was conducted. In the field,H. axyridis was one of the two large exotic lady beetle predators, with C. septempunctata also abundant.
These two coccinellids are both potential intraguild predators of a large community of small resident predators, including syrphid fly larvae, coccinellid larvae, and Orius insidiosus adults and larvae in addition to A. aphidimyza and C. carnea larvae.
Three treatments were designed to measure how IGP by large lady beetle adults on small predators impacted A. glycines populations.
The three treatments were: a predator exclusion cage, preventing all predators from accessing aphid populations, a medium mesh cage that allowed small predators to gain access to the cage but excluded large lady beetle adults, and a large mesh cage that allowed access by both large lady beetles and small predators.