It has been described the structure of 35 plots of different woods (beeches, oak grove, mixed woods and evergreen-oak forest) located in the Natural Park of La Garrotxa (Girona). The distribution of trees in diameter classes allow us to appreciate the state of maturity of forest sectors located in different orientations and altitudes the great densities are found in plots of young beeches and evergreen-oak forest. The mature woods have a low density and a large basis area. We have obtained growth curves from wood disks of 10 beeches and 9 oak cores removed using a Pressler increment borer. We have observed the great influence of the felling down of trees among ring increment. It has been done esteems of annual wood production: 4.29 t/ha in the beech and 2.43 t/ha in the oak woods.