Bedbugs (Cimex lectularius) were confined with bean leaves overnight in the laboratory in order to find out why bean leaves are used in the Balkan countries for bedbug control. The results indicate that bean leaves have no attractant action, but they act as traps by means of the small hooked hairs present on both sides of the leaves. The legs of the insect become entangled in these hooks. The seed pod of the common weed tick trefoil exerts a similar action. Other types of plant foliage that had no hooked hairs gave negative results.