When the first Europeans arrived in the 18th century to North America, they were astonished by the size of the giant, 1,000-year-old Douglas fir trees. If one lays down an old growth Douglas fir tree on a soccer field, it would cover the entire length of the soccer field. Seeing the opportunity, these settlers chopped these majestic trees down to build log homes and timer frame homes.
Douglas Fir is a heartier wood than most other softwoods and has a higher strength ratio. Engineers allow longer spans with Douglas Fir because of it’s strength. It also has a tendency to shrink less during the drying process.
The highest concentration of naturally produced toxins is present in the heartwood. The older the tree, the more concentrated are the toxins that make it resistant to fungi and insects. Species containing more heartwood than sapwood are much more naturally resistant. While species containing more sapwood than heartwood are less naturally resistant, they are easier to protect with the use of wood preservatives.
The Most Commonly Used Wood Species
US and Canada:
Pine (white, yellow and red), Eastern or Western white Cedar, Red Cedar, Cypress, Spruce, Balsam Fir, Douglas Fir, Hemlock, Ponderosa Pine, Lodgepole Pine and hardwoods such as Oak, Poplar and Walnut.
Douglas fir, Cypress, Larch, Redwood
The local availability of the wood species is a big factor in keeping costs down. Also, local climate plays a role in selecting the right kind of logs.
The Best Wood Species
OK, the bottom line: The top two wood species would be in most cases Douglas Fir and Cedar.
Que han hecho para corregir todo este mal al ambiente que han hecho