Those enjoying a cool beer in the garden this summer, at least in the southern half of England, may find an ambrosia beetle swimming about in it. These 6mm beetles, also known as oak pinhole borers, have a remarkable trick of cultivating ambrosia fungi, which produces alcohol, hence their liking for beer.
The beetles, Platypus cylindrus, carry spores of the ambrosia fungi about with them so that when colonising dead or dying trees they can start growing the fungus on which they and their offspring feed. One of the benefits for them in farming this particular fungus is that alcohol is toxic to many competing beetles and fungi so they carve out a patch untroubled by competition.
Scientists investigating the life cycle of these beetles used alcohol as bait on trees to attract them. Concentrations found in the average pint brought in the most beetles.
Until recently these beetles were relatively rare in Britain but the great storm of 1987 changed all that by providing a massive load of fallen and damaged timber. Unlike other wood boring beetles ambrosias do not pose a threat to healthy trees or furniture since they live on the fungus they farm.
