a1 AFRC Institute of Arable Crops Research, Rothamsted Experimental Station, Harpenden, Herts, AL52JQ, UK
Suction traps sampling at a height of 12·2 m have been operated by the Rothamsted Insect Survey since 1964 to monitor the aerial movement of aphids and other insects. Many variants of the trap have evolved in other countries due to the lack of a detailed published description. A standard for a low maintenance structure of the ‘12-metre' suction trap now being adopted by the Rothamsted Insect Survey and some other users is described. This should lead to better uniformity and comparability of data from such traps.
(Received June 30 1987)
p1 Present address: 12 Carisbrooke Road, Harpenden, Herts, AL5 5QT, UK.