Thaumetopoea processionea (Linnaeus, 1758)

Host plants:
The larvae feed on oak (Quercus).

Habitat:
Thaumetopoea processionea inhabits oak forests, oak lined streets and also individual trees.

Life cycle:
The egg always hibernates in disk-like batches on twigs. The larvae live from late April to early or mid-July. Pupation often takes place in the larval nests, but occasionally also under bark or moss. The adults are on the wing between August and September. Occasionally also pupae seem to hibernate (own observation in northern Bavaria in February 2007, additional rearing results). These should result in adults flying somewhat earlier (July).

Remarks:
Thaumetopoea processionea occurs from Southern and Central Europe (north locally to southern Sweden) to Asia Minor.

Thaumetopoea processionea has spread significantly since about 2000 and reached the eastern Swabian Alb since 2006. Global warming should be the cause. There is generally no danger for the infested trees because they thrive out again in July. The burning hair of the older caterpillars are admittedly a problem (heavy allergies) and justify spraying moult checker in human settlement areas, e.g. in shools. But outside there should be no spraying. Warning signs at focal points should suffice. Unfortunately some cities such as Schwäbisch Gmünd spray moult checker (e.g. Dimilin) from helicopter to woodland edges even prophylactically (e.g. in 2012). Many other insect larvae fall victim to such actions, even rare and protected ones!