583] ENGELMANN'—AMER. JUNIPERS OR SEC. SARlNA. 
The American Junipers of the section Sabina . 
By Dr. George Engelmann. 
The species of our Junipers, are, on the whole, well enough 
recognized, but their scientific definition is very insufficient—the 
characters, given in the books, vague and indefinite. 
I have had a good opportunity to study the different species 
and forms from all parts of our country, fresh and living as well 
as preserved in numerous collections; among them those con¬ 
tained in the great Herbaria of New York and Cambridge (Tor- 
rey and Gray) and those of Kew (Hooker), and especially those 
of Berlin, whence the types of the different Mexican species were 
sent to me by my late excellent friend, Alexander Braun. 
With the exception of Juniperus Sabina , which with us is al¬ 
ways a prostrate plant, all our species occur both in the form of 
low shrubs or of trees, a few of them of magnificent dimensions. 
In the arid mountain regions, the trunks of the different species 
which occur there frequently assume peculiar conical forms, very 
thick at base and rapidly tapering to a slender point. 
The bark is in most species thin, fibrous, and at last detached 
in shreds; only in f. pachyphlcea it is 1-3 inches thick, cracked 
like that of some oak or chestnut, the surface at last pealing off 
in thin layers. 
The wood is fine-grained and compact but not always hard; 
its growth is very slow, so that trees of 200 years have a diameter 
of 4-6, or, in the species growing in more generous soil and a 
more favorable climate, of 12-18 inches. Therefore, when we 
hear of mountain forms (necessarily of slow growth) having near 
their base.a diameter of 3 feet, we cannot help estimating their 
age* at a thousand years and upwards. In f. occidentals the 
annual rings are often quite eccentric. The resin is confined to 
the cambium layer and the inner bark; the wood is quite free 
from it but extremely durable, and, at least in f. Virginiana , 
almost indestructible. In this species the heartwood is red (hence 
the name Red Cedar) and very aromatic, soft, and splitting easily ; 
* This is also alluded to in a letter received, after the above was in type, from Sir J. D. 
which he speaks of the “ stupendous age ” of their Junipers, meaning probably y. occu 
dentalis. 
Missouri Botanical Garden 
George Engelmann Papers 
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