The species is particularly common on mature sessile oak trees in natural and semi-natural woodlands, where it often grows alongside mosses and other lichens.

While it occurs from sea level up to 440 metres in elevation, it is most frequently found in sheltered locations on tree trunks and large branches that are protected from direct rainfall.

The species epithet sylvicola is derived from the Latin word for "inhabitant of woods", alluding to its frequent occurrence in woodlands across western Britain.

In cases where visual identification proves challenging, chemical spot tests and analysis of the specific compounds present in the lichen provide the most reliable means of distinguishing L. sylvicola from its similar-looking relatives.

While oak is its primary substrate, it can also be found growing on other tree species including alder (Alnus glutinosa), downy birch (Betula pubescens), ash (Fraxinus excelsior), and rowan (Sorbus aucuparia).

In western British oak woodlands, it is often the dominant Lepraria species, typically growing on the rain-sheltered sides of tree trunks and large branches.

[2] In areas where its coverage is less extensive, the lichen can be found as part of diverse communities on sessile oak that include several rare or notable species from the Lobarion pulmonariae alliance.

These associated species include Arthonia vinosa, Catinaria atropurpurea, Pannaria conoplea, Phyllopsora rosei, Porina hibernica, and Rinodina isidioides.