Douglas Fir has the highest ratings of any western softwood for fiber stress in bending, tension to parallel to grain, horizontal shear, compression perpendicular and compression parallel to grain. Douglas Fir is often the standard against which all other framing species are measured. Its strength combined witha superior strength-to-weight ratio, high specific gravity, the moderate decay resistance of its heartwood, and documented excellent performance record against strong forces resulting from winds, storms and earthquakes, have given Douglas Fir its reputation. It is also tight knotted and close grained, adding the bonus of beauty to its structural capabilities. Color, grain pattern, knot size and type are addressed in the rules for appearance grades.