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Providing evidence to improve practice

Individual study: The ecology and economics of insect pest management in nut tree alley cropping systems in the Midwestern United States

Published source details

Stamps W.T., McGraw R.L. & Godsey L. (2009) The ecology and economics of insect pest management in nut tree alley cropping systems in the Midwestern United States. Agriculture, Ecosystems & Environment, 131, 4-8


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Use alley cropping Natural Pest Control

A controlled trial in 2004-2005 in Montana, USA (Stamps et al. 2009) found lower survival in pest alfalfa weevils Hypera postica from alley cropped plots than from a control without alleys on two of four sampling dates (19-58% vs. 41-73% larvae survived). Survival was similar with wide (24.4 m-wide) and narrow (12.2 m) alleys. Weevil fungal infection rates were higher in alley-cropped than control plots on two of four dates and parasitism was higher in narrow alleys than in wide alley and control plots on two dates. Alfalfa Medicago sativa yields were lower in plots with wide and narrow alleys (6,431-6,771 and 4,102-5,106 kg/ha, respectively) than in the control (8,800-9,223 kg/ha). Estimated costs were US$254-293/acre for wide and US$250-282/acre for narrow alley crops, compared with US$290-302/acre in the control. Predicted profit was only US$7-26/acre for wide alley crops and losses of US$-82 to US$-60 for narrow alley crops, compared with US$88-150 gains for the control. Alfalfa was established in a 2.5 ha plot within a black walnut Juglans nigra plantation using two distances between tree rows. A 2.5 ha control was planted with alfalfa monoculture. Weevil larvae were collected and reared in a laboratory to assess survival, fungal infection and parasitism.