Ponderosas are a species of pine tree found all over the mountains of the western US. They are tall, straight trees which are very valued as timber. They begin as conical-shaped trees but the tops get flattened out with age. Ponderosa pines have bark which smells like vanilla. These pines have evolved with fire and generally are fire resistant. the type of small fire which was once common in ponderosa forests burned off excess duff, returned nutrients to the soil, and removed competitors from the forest. However in the days of fire supression, dead wood has built up and there is the danger of crown fires which will destroy whole forests.