huangyhg

hardwood and softwood classes in nds
i can not find a clear classification for softwood and hardwood in nds. for example, is southern pine softwood or hardwood in nds's. where can i find the detailed category for softwood and hardwood? thanks.
softwoods are carniferous, hardwoods are desiduous. it is not a function of the density of the wood, though hardwoods are typically denser and, well..... harder.
southern pine is a softwood.
a good resource for information on wood is the usda forest products lab (fpl) book "wood handbook". you can download it here (free .pdf)
deciduous trees are typically hardwoods, but there are also many hardwood evergreens.
regarding softwoods and hardwoods, almost all framing lumber such as 2x4 - 2x14 are manufactured out of softwoods. in most cases hardwoods are more valuable for their use in non-structural applications.
today with all the different engineered wood products on the market some hardwoods are being used to produce lvl & psl products.

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