CHAP. CXIII. 



CONl'FERiE. PI'CEA. 2331 



£ P. p. 4 cintova, Plnus Picea cintrea Baum. Cat., cd. 1835, is a low plant with greyish hark, 

 not yet introduced. 



Description. The silver fir, the noblest tree of its genus, except P. Webb- 

 iana, rises to the height of from 160 ft. to 180 ft., with an erect stem, regularly 

 furnished with whorls of candelabrum-like branches. The trunk, in tull-grown 

 trees, is from 6 ft. to 8 ft. in diameter, covered, till its fortieth or fiftieth year, 

 with a whitish grey bark, tolerably smooth ; 

 but, as it increases in age, becoming cracked 

 and chapped. At a still greater age, the 

 bark begins to scale off in large pieces, 

 leaving the trunk of a dark brown colour 

 beneath. The branches stand out horizon- 

 tally, as do the branchlets and spray, with 

 reference to the main stem of the branch. 

 The leaves, on young trees, are distinctly 

 two-rowed, and the general surface of the 

 rows is flat ; but, as the trees advance in 

 age, and especially on cone-bearing shoots, 

 the disposition of the leaves in rows is less 

 perfect. The leaves are, in every stage of the tree's growth, turned up 

 at the points; but more especially so on old trees, and on cone-bearing 

 branches. The leaves are of a darker green above than those of any other 

 fir ; and underneath they have two white silvery lines running lengthwise 

 on each side of the midrib. As the leaves are partially turned up, 

 these silvery lines make a conspicuous appearance in the general aspect of 

 the tree ; whence its name. The cones are large, and have a magnificent 

 appearance, both before and after they are mature. They are cylindrical, 

 erect, and bluntly pointed at both ends. When nearly full grown, the scales 

 are of a fine red ; and the bracteas are long, and of a light green. The seeds 

 are of an irregular form, enveloped and surmounted with a membranaceous 

 wing, somewhat broader above than below. The roots spread horizontally, 

 not so near the surface as in the spruce fir. They extend to a great distance, 

 and are not so abundantly furnished with fibres as in the case of most of the 

 spruces, nor have they a conspicuous taproot, as is the case, more or less, with 

 all the genus Pinus. The rate of growth of the tree is slow when young, but 

 rapid after it has attained the age of 10 or 12 years. The following scale of the 

 progress of the silver fir in the Jura, in France, is given by Baudrillart ; but 

 its growth in England is much more rapid. The first year, it rises in five or 

 six weeks after it has been sown, with five or six leaves, and is about a in. 

 in height. The second year, it advances 1 in., retaining the leaves of the 

 first year. The third year, it advances from 1 in. to 2 in., indicating the 

 rudiment of a small lateral branch. The fourth year, it advances about 2 in., 

 showing a second lateral branch ; and, if taken up at this time, the plant will 

 be found to have a small taproot. The fifth year, it begins to grow somewhat 

 more freely, but still so slowly, that, unless under very favourable circum- 

 stances, the plants are seldom found, at that age, above 9 in. or 1 ft. in height. 

 About the eighth year, they begin to increase more rapidly; gradually length- 

 ening the annual growth of the leading shoot, till, at their 20th year, it is from 

 2 ft. to 3 ft. in length. Cones with fertile seeds are seldom produced before 

 the tree has attained its 40th year ; though cones without seeds often appear 

 before half that period has elapsed. The female catkins are often produced for 

 years together, without any males appearing on the same tree. In the Jura, a 

 silver fir, at the age of 20 years, is commonly from 9 ft. to 10 ft. in height, with a 

 trunk from 12 in. to 1ft. 4 in. in circumference. After this, it increases in 

 height at the rate of from 1 ft. 8. in. to 2 ft. 2 in. a year. At 40 years' growth, 

 the trunk is from 3 ft. to 3 ft. 6 in. in circumference ; at 50 years, from 4 ft. to 

 5 ft. ; at 60 years, from 6 ft. to 8 ft. ; at 75 years, from 10 ft. to 1 1 ft. 6 in. ; 

 and, at 100 years, about 13 ft. From 100 to 120 years' growth is necessary 

 to produce a tree of from 114 ft. to 130 ft. in height : after which period, it 



