Fact of the week
In Britain we have two native species of oak which look very similar. This is how to tell them apart: pedunculate oaks (Quercus robur) produce acorns which hang on a stalk or peduncle while the acorns of the sessile oak (Quercus petraea) are stalkless.
Left: sessile oak; right: pedunculate oak. Header image: the oak by the bridge between Sleepers and Cornfield photographed by Ian Bushell