APPENDIX 



Identification Characteristics of Black Spruce 



Although trees of black spruce and white spruce usually can be dis- 

 tinguished at first glance by persons who are familiar with these 

 species, newcomers often experience considerable difficulty in correctly 

 identifying them. The taxonomic characteristics as given in botanical 

 keys and descriptions provide positive means of identification, but 

 these are not always easy or convenient to check. Several character- 

 istics that have proven useful in making quick determinations are 

 described below : 



1. Cones. — Black spruce cones are borne in a cluster at the top of the tree, 

 are egg-shaped before they open and remain on the tree for many years. They 

 are purple in color before ripening, rich reddish brown after ripening, and finally 

 become gray or blackened. White spruce cones fall within 6 to 12 months after 

 maturing and, accordingly, can be found in large numbers on the ground under 

 cone-bearing trees ; and are borne scattered over the top and sides of the crown, 

 are rather cylindrical in shape before opening, green in color before ripening, 

 and straw-colored to brown afterwards. These differences are positive. 



2. Crown form. — Young black spruce are conical in shape and very symmet- 

 rical, but older trees have slender, comparatively unsymmetrical crowns with 

 irregularly spaced branches (figs. 15 and 19). White spruce have broader 

 crowns with regular symmetrical branches. Crown form differences do not give 

 positive identification but are helpful in viewing trees from a distance. 



3. Twigs. — The 1-year-old twigs on black spruce are dull brown. On white 

 spruce they are smoother, almost glossy, and straw-colored. Twig differences 

 are useful for small trees before cones are borne. Rarely a doubtful twig is 

 found that cannot be identified with certainty. 



4. Bark. — The freshly exposed bark surface on mature or nearly mature black 

 spruce as determined by peeling off a bark scale with a knife is greenish-yellow. 

 On white spruce it is pink or pinkish-yellow. This is a positive test for use on 

 logs or tall trees where twigs or cones cannot be examined. 



5. Odor of crushed needles. — Some persons find a marked difference between 

 the pleasant resinous odor of crushed black spruce needles and the pungent, dis- 

 agreeable odor of white spruce (skunk spruce, cat spruce). Since the acuteness 

 of the sense of smell of individuals differs greatly, one should not rely on this 

 test until he has determined by trial that he can unfailingly detect the difference 

 in ordor. One difficulty is that in checking several trees, the fingers soon become 

 impregnated with the odors of both species. 



6. Seedlings. — Most newly germinated black spruce seedlings (76 percent) 

 have four cotyledons, 3 percent have only two or three seed leaves, and 21 per- 

 cent have five or six. Most white spruce seedlings have six cotyledons (82 per- 

 cent), and the remainder have four or five cotyledons. Thus, by checking the 

 number of seed leaves on new reproduction a reasonably accurate estimate can 

 be made of the species or species mixture. This is the only method for ocularly 

 distinguishing new seedlings. 



PEELED PULPWOOD BOLTS 



Peeled spruce and balsam fir pulp wood bolts can be distinguished 

 on sight only after long experience, and perhaps even then with some 

 margin of error. Black spruce and white spruce bolts are even more 

 difficult to differentiate. 



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