Hazel dormice typically inhabit broadleaved woodland, scrub, and hedgerows composed of native shrub species. As their name suggests, hazel dormice are closely associated with hazel (Corylus avellena) and they utilise hazelnuts as an important food source in autumn. Dormice are not found exclusively in woods with hazel however, and can live in habitats where hazel is absent. The most important factors required for dormouse habitat are: a tree or shrub structure that allows dormice to move around freely and safely off the ground; a good supply of natural food throughout their waking year; dense foliage or nest holes in which to build nests to breed and raise young during the summer; and suitable, undisturbed places to hibernate at ground level. Hazel dormice can also be found in some conifer woodland and they are occasionally recorded in gardens and other less predictable habitats.
Hazel dormice live mostly in deciduous woods with a well-developed understory and in most parts of their range they prefer the early successional stages of woody vegetation over the high canopy, unmanaged woodland that is so common in our current landscape. This is reasonable, as a woodland in active, sympathetic management, such as coppice or coppice with standards, results in a varied age structure, allowing a variety of plants to flourish in different areas of the wood in any one year, thus providing consistent sources of food and nesting habitat for dormice in the wood. Well-managed, ancient woodland would be an ideal habitat for dormice, as the longstanding nature of the wood (‘ancient’ in this case means a continuous woodland on the site since at least 1600) would provide a wide range of species and the existing management should give a good structure.
It is most likely that the name ‘hazel’ dormouse came about because hazel coppice was where dormice were most often found, by coppice workers coming across hibernating dormice during winter. This would simply be because hazel coppice was the most common form of worked coppice in the hazel dormouse range, so where most coppice-workers were working!