Oak Processionary

The oak processionary (Thaumetopoea processionea) is a moth whose caterpillars can be found in oak forests. They may pose a human irritant because of their poisonous setae (hairs), which may cause skin irritation and asthma.
== Description ==
The wingspan of adult stage moths is between 25 and 35 millimetres (0.98 and 1.38 in). Their pattern of tan, brown and white make the adults difficult to see against oak bark. Adults fly during July and August. The larvae construct communal nests of white silk from which they crawl at night in single file, head to tail in large processions to feed on foliage in the crowns of trees, returning in the same manner.
Oak is its preferred food source, but the moth also eats the leaves of hazel, hornbeam, sweet chestnut, birch and beech.
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