KEY TO SPECIES 283 



6. Resin ducts mostly conspicuous, not numerous. 



61. Resin ducts very small, mostly invisible to 



naked eye. Marked contrast in color 

 between heartwood and sapwood. Color, 

 yellowish brown. 



TAMARACK Larix americana 



62. Resin ducts somewhat larger, usually visible 



to naked eye; oval in cross-section. 

 Grain usually straight, sometimes wavy. 

 Color reddish yellow or dark red. 



RED FIR Pseudotsuga taxifolia 



2. Heartwood and sapwood nearly the same shade. 

 a. Resin ducts mostly small, scattered and scarcely 

 visible without lens, being of same color as sur- 

 rounding wood. Wood light, soft and uniform 

 throughout; color white or very light. 



RED SPRUCE Picea rubens 



B. Resin ducts mostly absent; sometimes present as a 



result of injury. 

 1. Heartwood and sapwood of different color. 



a. Resin cells numerous, often conspicuous to naked 

 eye. 



01. Odorless and tasteless. Sapwood thin, straw- 



colored to nearly white, heartwood light 

 cherry. Texture coarse. Resin masses 

 in resin cells prominent; appear (under 

 lens) as rows of black or amber beads, 

 when cells are cut lengthwise. 



REDWOOD Sequoia sempervirens 



02. Aromatic odor, little difference in spring and 



summer wood, sapwood white, heartwood 

 deep reddish brown, occasional flecks of 

 white sapwood found in the heart. Resin 

 cells very numerous, deeply colored, visible 

 under lens, but do not have bead-like 

 appearance. 



RED CEDAR Juniperus mrginiana 



