PINUS 169 



any other genus in the northern hemisphere. They are evergreen, and 

 range from trees over 200 ft. high to mere shrubs; very resinous, producing 

 their branches in tiers. 



The leaves of pines are nearly always produced in clusters or bundles 

 of from two to five, occasionally there are six, and in one species 

 monophylla they are solitary. The seedling leaves of all pines are 

 solitary, the adult condition commencing to appear in the second and 

 third years. The individual leaf or "needle" is long and narrow, mostly 

 finely toothed at the margin, and always more or less conspicuously lined 

 with rows of minute white, or whitish, dots called stomata. Where the 

 leaves are in bundles of two the transverse section of each is semicircular, 

 in the bundles of three to five they are three-sided. Each bundle of 

 leaves, whatever their number, forms in the aggregate a slender cylinder. 

 At the base of each bundle is a "sheath," whose varying length and 

 duration give very useful indications of the identity of the species. The 

 leaf-bearing shoots of each season are always to a greater or less extent 

 naked at the base, being furnished there with "scale-leaves" only small, 

 thin, membranous bodies, often fringed, and usually falling away quickly. 

 The terminal winter bud is an important differentiating character according 

 to its shape and size, the character of the scales by which it is covered, 

 and whether it be resinous or not, although in some species the last 

 character is uncertain. 



The flowers of pines are unisexual and borne in conical clusters, the 

 males at the base, the females at the apex of the year's growth ; the female 

 inflorescence develops the second year into a woody fruit often of great 

 size and weight, commonly known as a "cone," and of egg-shaped, 

 cylindrical, or tapered form. These cones are composed of a number 

 of woody scales which vary in length, in thickness, and in the character 

 of the scar or boss at the end, and in the presence or absence of spines. 

 When the cone is ripe (most frequently at the end of the second year), 

 the scale opens and allows the two seeds at its base to escape ; but some 

 species take longer, and several appear never to release their seeds at 

 all unless through some outside agency such as fire (in the West American 

 forests), or squirrels, or birds. Some species have small seeds which are 

 furnished with a large membranous wing whose object is to assist in their 

 dispersion. The larger, edible seeds have only rudimentary wings or 

 none at all. 



As garden or park trees the pines are of varying merit, but the best 

 of them are amongst the noblest of evergreens. They do not need a 

 rich soil so much as an open, well-drained one. The hardier ones, like 

 montana, sylvestris, and Banksiana, grow in some .of the most inclement 

 parts on the globe. On nearly all the mountains of the northern world 

 it is some member of this genus that makes the highest timber line. For 

 chalky soils, Brutia, halepensis. excelsa, Laricio, Pinea, and others 

 succeed very well ; whilst for spots exposed to sea-gales and in maritime 

 situations generally, the Austrian pine, radiata, Pinaster, and Thunbergii 

 are extremely useful in building up the first line of protection from sea- 

 winds. The purely garden varieties have to be increased by grafting on 

 the types to which they belong, but all other pines must be grown from 

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