Not to nitpick, but "hardwoods" means deciduous trees and "softwoods" means coniferous trees. Technically, balsa is a hardwood and Douglas Fir is a softwood although working with each one would lead you to believe otherwise.
Like bladeprince mentioned, basswood makes for an excellent carving wood. Soft enough to work easily and it keeps crisp details. Poplar is another easiy-to-carve wood, although it often has a greenish look to it.
By the way, great example, Jeff. Look at a woodworking catalog for examples of dedicated carving knives that wouldn't be and EDC.