_a._ Heart-wood light orange red; sap-wood, pale lemon; wood, heavy and hard .........................................YEW. _b._ Heartwood purplish to brownish red; sap-wood yellowish white; wood soft to medium hard, light, usually with aromatic odor, ...................................RED CEDAR. _c._ Heart-wood maroon to terra cotta or deep brownish red; sap-wood light orange to dark amber, very soft and light, no odor; pith rays very distinct, specially pronounced on radial section ..................................REDWOOD. 3. Heart-wood present, color only different in shade from sap-wood, dingy-yellowish brown. _a._ Odorless and tasteless ........................BALD CYPRESS. _b._ Wood with mild resinous odor, but tasteless ....WHITE CEDAR. _c._ Wood with strong resinous odor and peppery taste when freshly cut, ................................INCENSE CEDAR. B. Resin ducts present. 1. No distinct heartwood; color white, resin ducts very small, not numerous ............................................SPRUCE. 2. Distinct heart-wood present. _a._ Resin ducts numerous, evenly scattered thru the ring. _a.'_ Transition from spring wood to summer wood gradual; annual ring distinguished by a fine line of dense summer-wood cells; color, white to yellowish red; wood soft and light .......................SOFT PINES.[2] _b.'_ Transition from spring wood to summer wood more or less abrupt; broad bands of dark-colored summer wood; color from light to deep orange; wood medium hard and heavy ............................HARD PINES.[2] _b._ Resin ducts not numerous nor evenly distributed. _a'._ Color of heart-wood orange-reddish, sap-wood yellowish (same as hard pine); resin ducts frequently combined in groups of 8 to 30, forming lines on the cross-section (tracheids with spirals), ..............DOUGLAS SPRUCE. _b'._ Color of heart-wood light russet brown; of sap-wood yellowish brown; resin ducts very few, irregularly scattered (tracheids without spirals) ........TAMARACK. [Footnote 1: Soft and hard pines are arbitrary distinctions and the two not distinguishable at the limit.]