My reference says that Dry California Spruce weighs 42 pounds per cubic foot
KD stands for Kiln Dried.
Kiln-dried lumber is generally of higher quality than air-dried lumber because it is dried in a controlled environment, resulting in more consistent moisture content and reduced risk of warping or cracking.
Kiln-dried lumber is better for woodworking projects than green lumber because it is less likely to warp or shrink. Kiln-dried lumber has lower moisture content, making it more stable and easier to work with. Green lumber, on the other hand, has higher moisture content and is more prone to warping and shrinking as it dries.
Kiln dried lumber offers several benefits for woodworking projects. It is less likely to warp, shrink, or crack compared to air-dried lumber, making it more stable and easier to work with. Kiln drying also helps to remove excess moisture, reducing the risk of mold and insect infestation. Additionally, kiln dried lumber tends to have a more consistent moisture content, resulting in a higher quality finished product.
Douglas Fir most likely
Green lumber is freshly cut and contains a high moisture content, making it prone to warping and shrinking as it dries. Kiln-dried lumber has been dried in a controlled environment, resulting in a more stable and less prone to warping material, making it more suitable for construction projects.
Lumber must be seasoned to prevent it from cracking and warping. After being cut into boards, the lumber is dried (seasoned) in a heated drying shed called a kiln or in the open air.
Seasoned lumber has been dried, usually in a lumber kiln, to roughly 6% to 8% moisture content. Unseasoned lumber may be anything from dripping-wet-fresh-from-the-tree to air dried, depending on how long it's been sitting at the lumberyard and on the local humidity.
Kiln-dried lumber is stronger and more stable than green lumber due to the removal of moisture, resulting in less warping and shrinking. This leads to better structural integrity and performance in construction projects. Green lumber, on the other hand, is more prone to warping and shrinking as it dries, which can affect the overall stability and longevity of the structure.
In my experience, Kiln dried has been most effective to me for fires. If that is what you are referring to then, go for KILN DRIED.
Kiln dried cedar is cedar that has been dried through a heating process. This is done in a kiln.
G. L. Comstock has written: 'Dimensional changes in kiln-dried softwood lumber after surfacing and during storage' -- subject(s): Lumber, Testing, Drying, Evaluation