ENUMERATION OF CONIFERS 303 



Section I. Cembra 



Umbo of cone-scales terminal; scales of the young cone unarmed: leaves 

 in fascicles of 5, with deciduous sheaths. 



Group 1. Cembra 

 Seeds wingless; cone indehiscent, deciduous at maturity. 



1. P. koraiensis, Sieb. & Zucc. (P. viandshurica, Rupr.). Korean P. 

 Pyramidal tree to 100 feet tall; bark gray or gray-brown, thin, peeling off 

 in irregular flakes, red-brown beneath; branchlets with yellowish-brown 

 pubescence; winter-buds oblong-ovate, acuminate, dark chestnut-brown: 

 leaves straight, dark green and glossy on the back, bluish-white on the inner 

 sides, 23^-4 inches long: cones short-peduncled, conic-oblong, yellowish- 

 brown, 4-6 inches long; scales rhombic-obovate, with recurved obtuse apex; 

 seed over 3^ inch long, brown, sharply edged. Japan, Korea. — Introduced 

 1861 to Great Britain and some years later to this country. Hardy as far 

 north as southern Ontario and New England. A handsome tree of pyramidal 

 habit and rather slow growth; one of the best hardy pines for smaller gardens. 



2. P. Cembra, L. Swiss Stone P. Tree to 70 or sometimes 120 feet tall, 

 with spreading usually short branches forming a narrow dense pyramid, in 

 old age often with very picturesque, broad, open, round-topped head; bark 

 greenish-gray and smooth on young trees, on old trunks reddish-gray and 

 divided into thin scaly plates; branchlets coated with dense yellowish-brown 

 tomentum; winter-buds globose-ovoid, long-acuminate: leaves straight, dark 

 green on back, bluish-white inside, 2-5 inches long, with medial resin-ducts: 

 cones short-peduncled, ovate, obtuse, light brown, 23^^-33^ inches long; scales 

 broadly ovate, rounded at apex, apophysis much broader than high; seed 

 }/2 inch long. Alps of central Europe and from northeastern Russia to Mon- 

 golia. — Hardy as far north as Saskatchewan. Handsome hardy pine of 

 symmetrical dense habit when young and of slow growth. The large seeds 

 are edible. 



Var. columnaris, Beiss. A form of narrow columnar habit. 



Var. sibirica, Loud. (P. sibirica, Mayr). Siberian Stone P. A form with 

 shorter leaves and larger cones; of narrower habit and more vigorous growth. 



A closely related species is P. pumila, Regel (P. Cembra var. piwiila. Pall.). 

 Dwarf Stone P. Shrub to 10 feet high, with the main branches usually pros- 

 trate: leaves 1^-3 inches long, obscurely serrulate, with the resin-ducts 

 usually marginal: cone ovoid, Ij^^-l^ inches long. Northeastern Siberia 

 and high mountains of Korea and Japan. — Introduced to Europe before 1817, 

 to the Arnold Arboretum in 1915 by E. H. Wilson. It is probably as hardy 

 as the preceding species, but does not seem to do well under cultivation. 



3. P. albicaulis, Engelm. Whitebark P. Tree tt) 30 or rarely to 60 feet 



