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WHITE PINE. 

 Pinus Strobus, Linnaeus. 



FORM At present seldom exceeding 3 ft. in diameter and 125 ft. in height, usually 50-90 ft. 

 high and 15 to 3 ft. in diameter. When grown in dense stands (Figs. 1 and 10) the trees are 

 tall, straight, free from lateral branches for a considerable distance from the ground, have 

 little stem-taper and shallow crowns. When grown in the open (Fig. 34, specimen on left), it 

 has much stem-taper is relatively low, often forked, covered with persistent lateral branches 

 almost to the ground which make it attractive ornamentally but of low commercial value. 



BARK On young branches, thin, smooth, greenish -brown; later scaly and darker. On old trees 

 thick, dark gray, and divided by long and shallow fissures into broad longitudinal ridges (See 

 Fig. 44.) 



- TWIGS Slender, flexible, at first hairy, slightly roughened by raised leaf-scars. New growth 

 at first light green and erect. During first winter light brown in color, less erect in position, 

 very resinous if punctured. 



BUDS In terminal cluster, ovate-oblong, sharp-pointed, with numerous brown, long-pointed 

 and overlapping scales. Apical bud I-* of an inch long. Lateral buds about i of an inch long. 



LEAVES Light green when young and bluish-green, soft, flexible, 2|-5 inches long when 

 mature; persist usually until end of second season, occur in clusters of five, are -triangular in 

 cross-section, contain one fibro-vascular bundle, have finely serrate edges and are surrounded 

 at the base by a deciduous sheath. 



FLOWERS Appear about May. Staminate flowers clustered at base of new growth of season, 

 yellow, oval, about i of an inch long. Pistillate flowers solitary or in small groups, lateral 

 along new growth, pinkish-purple, cylindrical, about 1 of an inch long. 



FRUIT A cone maturing in two seasons, 5-10 inches long, drooping, stalked, slightly curved, 

 and covered with thin unarmed scales without thickened apex. Seeds are winged, J of an inch 

 long, dark brown in color on both sides and mottled with black spots. 



WOOD Non-porous; resinous, soft, straight-grained, easily worked, light brown except sapwood 

 which may be almost white. Weighs 24.04 Ibs. per cubic foot. Formerly used for a wider range 

 of purposes than any other native species and adapted for practically all uses except where 

 strength, hardness, flexibility and durability in contact with soil are required. 



DISTINGUISHING CHARACTERISTICS The White Pine is the only species of Pine native 

 to eastern North America which has soft, flexible, bluish-green needles in clusters of five. The 

 lateral branches, usually 3-7 in a whorl, are arranged in distinct horizontal layers. The cones 

 are 5-10 inches long, long-stalked, and their cone-scales are thin, flat, and unarmed. 



RANGE Newfoundland to Manitoba on the north, south through northern states to Penn- 

 sylvania and along the Allegheny Mountains to Georgia, and southwest to Iowa. 



DISTRIBUTION IN PENNSYLVANIA Common in the mountainous portion of the State. 

 Originally formed heavy stands especially in the central and northern parts of the State. Some- 

 times pure but usually mixed with other species. Found sparingly in the southwestern and south- 

 eastern parts where it is usually limited to cool ravines and north slopes. Rarely found at present 

 in valleys like the Cumberland, Lancaster, Chester, lower Lehigh and lower Delaware. 



HABITAT Prefers a fertile, moist, well-drained soil, but will grow well on dry sandy, 

 soils and gravelly slopes. Common on banks of streams, river fiats, in hollows and ravines, 

 but rarely found in swamps. Any habitat in its natural range will be favorable to its develop- 

 ment except swamps and ridges exposed to severe winds. 



IMPORTANCE OF THE SPECIES White Pine is one of the most important timber trees of 

 the United States. It is indigenous to America but was introduced into England by Lord Wey- 

 moutb in 1705 and shortly afterwards into Germany where it is no longer regarded an exotic 

 species but a naturalized member of the German forest. This species can be recommended for 

 forestry purposes, because it may be regenerated successfully both naturally and artificially 

 as shown by the numerous and extended German experiments. It adapts itself to a great 

 variety of soil conditions, is a rapid grower, is very attractive ornamentally, and will thrive 

 in pure or mixed stands; but the latter are best on account of less danger from disease, better 

 natural pruning, and earlier financial returns from thinnings. 



