This is due to the greater resin and lignin content of these woods. Softwoods are easy to ignite and they burn rapidly, producing a very hot fire of relatively short duration. They are an excellent choice for use as kindling when starting a fire. Softwoods are generally considered inferior to hardwoods, however, because they burn out quickly and require frequent attention. If you burn them green you will have a greater build-up of creosote and need to clean your chimney more frequently.
Native conifers found in New Hampshire include white and red pine and eastern hemlock.
Pound for pound of dry wood, all species of hardwoods have approximately the same heat value. These woods burn slowly, with a low flame, and produce steady glowing coals. Species such as basswood, aspen, willow, and the hybrid poplars produce very light woods. These woods burn very quickly and a cord will produce from 40 to 50 percent less heat than the more dense hardwood. It is always best to burn seasoned, dry wood.