Many wood plants that are devoid of showy flowers and are seemingly uninteresting to bees can become important sources of honey: these are the plants that produce honeydew. Oaks, beeches, maples, willows and many other trees, bushes and grasses produce honeydew as a consequence of the attack of insects who puncture the leaves and buds to suck the lymph. The bees collect the sugary substance left on the leaves drop by drop. Of the many insects responsible for this production, one of them, called Metcalfa, originated in