You need to be able to tell the two species of British Oak from one another in order to record either in your WFS diary. So which is which?
The problem for many beginners is that hybrids between English or Pendunculate Oak (Quercus robur) and Sessile Oak (Quercus petraea) are common - known as Quercus x rosacea. Beginners may feel rather overwhelmed by mention of plant hybrids. But it is the existence of hybrids that makes identification difficult. Generally, hybrids are intermediate in characters.
Quercus x rosacea often looks closer to Quercus robur, usually having a slightly lobed base to the leaf but has a leaf stalk, like Q. petraea
Oaks are a species that require you to look at a combination of characters to get a correct identification.
| Quercus robur | Quercus petraea | |
|---|---|---|
| Habitat | Wet Loams and clays | Lighter sandy soils |
| Acorns | Stalked | not stalked |
| Leaf stalk (or petiole) | None | Stalked |
| Hairs on underside of leaf | None | Stellate hairs along mid-rib |
| Base of leaf | Distinct lobed base known as auricles | Tapering base without auricles |
Further reading and references