Gastropacha quercifolia (Linnaeus, 1758)

Host plants:
The caterpillars feed on deciduous trees like Prunus, Malus, Crataegus, Salix, Rhamnus or Frangula.

Habitat:
Gastropacha quercifolia colonizes grove rich areas like wetlands, coppice woods, hedgerows, bushy grasslands, woodland edges and usually occurs in more humid areas. But it is missing at least nowadays large parts as for example the Swabian Alb almost entirely.

Life cycle:
The caterpillar overwinters free on branches, mostly in the inner area of the woods, and often rather close to the ground, often on small branches that grow directly from the trunk and usually on the underside of them. I observed such caterpillars in the 1980s near Memmingen in blackthorn hedges at the forest edge between the spruce forest and wet meadows where also the bumblebee moth was common. But for over 15 years there was no further evidence more, probably because of the decline of the hedges and the strengthening and straightening of the meadows. The caterpillars are usually mature in June. The moths fly from late June through August.
In September 2009, I found some caterpillars on the small apple tree in the garden of my parents near Memmingen. This tree is growing in full sun in a damp nature meadow.

Endangerment: strongly endangered

Endangerment factors:
Gastropacha quercifolia is highly threatened by the decline of suitable habitat due to the tivialization of the landscape and possibly other factors that are not yet fully understood. The tit mast by winter feeding and nesting boxes inflation should be locally disadvantageous, too, because the artificially high bird population finds the last larva in winter.

Remarks:
Gastropacha quercifolia occurs from Northern Spain across much of Europe and the more temperate Asia to Japan.