Estovers is the right to have wood from the Forest for fuel. The Forestry Commission used to pay people to give up the right of estovers, so not many properties still have it today. Taking wood from the Forest is theft, and cutting the Forest trees without permission is criminal damage.
Stacked firewood is measured in ‘cords’. A cord is 128 cubic feet, which would be a stack 4ft by 4ft by 8ft. The volume includes the air between the logs, so the amount of actual wood depends on how closely the logs are stacked. The pile of logs in the picture is about two cords. It’s about 4 feet high, and the logs are 8 feet long. Keeping a house warm through the winter would have taken quite a few cords of wood!