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Providing evidence to improve practice

Individual study: Impact of tillage on the crop pollinating, ground-nesting bee, Peponapis pruinosa in California

Published source details

Ullmann K.S., Meisner M.H. & Williams N.M. (2016) Impact of tillage on the crop pollinating, ground-nesting bee, Peponapis pruinosa in California. Agriculture, Ecosystems & Environment, 232, 240-246


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Pollination: Use no tillage in arable fields Mediterranean Farmland

A replicated, randomized, controlled study in 2012–2013 in an irrigated squash field in the Central Valley, California, USA, found more soil-nesting bees in plots with no tillage, compared to deep tillage. Pollinator numbers: More Peponapis pruinosa squash bees emerged from nests in plots with no tillage, compared to deep tillage (11 vs 8 bees/cage). Methods: In August 2012, bee nests were established in 20 plots (3 x 3 x 1.8 m field cages), each of which contained drip-irrigated squash plants. Deep tillage (disking, ripping, and subsoiling: 41 cm maximum depth) was used on 10 of these plots, in autumn 2012. Emerging bees were collected in blue vane traps (26 May–26 September 2013).