"Dimensional" lumber is the general name for framing lumber. What we stock is a framing grade of spruce in an assortment of sizes and lengths. An important thing to know is that with most any dimensional lumber, there is a difference between what the board is called, and what it truly measures.
In the past, when a timber was called a 2x4 [or "two-by-four"], it actually measured 2 inches by 4 inches. Now, most timber is milled and planed to give it a little more of a finished look, and a little more of a consistent size and profile. Because of this extra milling, a 2x4 no longer measures a full 2 inches by four inches. Instead, a 2x4 is really only 1 1/2" by 3 1/2".
The same is true of pine. A 1x6, for example, actually measures 3/4" x 5 1/2". In this case, the planing is necessary for a smoother surface, so that the board could be used for interior applications.
The length of the boards is generally exactly what you order, though we usually only stock pieces of even lengths. The usual lengths are 8', 10', 12', 14', and 16'. In some of the larger timbers, like the 2x8's, 2x10's, and 2x12's, we also stock longer lengths (some up to 24'), since these are often used as rafters or for floor joists, where longer is usually better.