Individual study: Management experiments on aphids (Acyrthosiphon spp.) and beneficial insects in lucerne
Cameron P.J., Allan D.J., Walker G.P. & Wightman J.A. (1983) Management experiments on aphids (Acyrthosiphon spp.) and beneficial insects in lucerne. New Zealand Journal of Experimental Agriculture, 11, 343-349
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
Leave part of the crop or pasture unharvested or uncut
A controlled trial from 1978-1980 at Pukekohe, New Zealand (Cameron et al. 1983) found a higher ratio of predators to aphids Acyrthosiphon spp. in five out of seven periods in a plot where strips of alfalfa Medicago sativa were left uncut than in a fully cut plot. The plot with uncut strips had fewer aphid outbreaks (two aphid outbreaks in seven interharvest periods) than a fully cut plot (four aphid outbreaks). Peak aphid numbers on alfalfa stems were also higher in the fully cut plot (5.5-400.3 aphids/stem) than the plot with uncut strips (0.6-124.6 aphids/stem). Two 40 x 60 m plots were compared: one continuously-cut plot and one strip-cut plot. In the strip-cut plot, two 10 m-wide strips were cut when the continuously-cut plot was mown, the remaining two strips were cut when the previously cut strips were half-grown. Aphids were sampled by sweep netting (50 sweeps/plot) and counting aphids on 10 alfalfa stems at six points along one transect/plot.