Jerome
Thanks Warren for the localization.

As an addendum, sorb (or « Cormier ») is not « hard » as « difficult to carve », but very dense (like 0.9, barely floats), very resistant to wear (thanks to its very fine texture) but quite nice to work with. My 8 by 8 by 68cm jointer weights 4.4kg. Heavy.

It is the most commonly found wood for good wooden antique planes in France. Maybe because the other already rot or got eaten by pests.

Hornbeam and beech are more modern and somewhat second choice. Sometimes making the bulk of the body with a laminated sorb sole.

Green oak is hard in every sense of the word. It’s rare though. Maybe more common in Italy, where those grow bigger and faster.