conifers. SILVA OF NORTH AMERICA. 3 



in the middle Atlantic states, and in the lowlands of the south eight species are found. In western 

 North America Pine-trees are distributed over all the mountain ranges and elevated valleys from 

 Alaska to the Mexican boundary, which is crossed by five Mexican species finding their northern home 

 on the mountains of southern California, Arizona, and New Mexico. At the north Pine-trees form 

 great forests on many of the interior ranges of the Pacific states, and at the south, mingled with 

 Junipers, frequently cover elevated plains and mesas ; they are found at the timber line on all high 

 mountains, maintaining a foothold where no other tree can live ; they bear uninjured the fiercest ocean 

 gales, and flourish in the arid valleys of the interior, where neither cold nor drought is able to check 

 their vigor. 



The type is an ancient one. Represented by a few species in the cretaceous flora of North 

 America and Europe, it became abundant in the miocene period, when at least one hundred species of 

 Pines are believed to have existed. 18 



Pinus contains some of the most important timber-trees of the world ; and the straight-grained 

 moderately hard resinous wood of many species is used in immense quantities. The most valuable 

 timber-trees of the genus are the eastern American Pinus palustrls, Pinus Strobus, and Pinus echi- 

 nata, the western American Pinus Lambertiana, Pinus ponderosa, and Pinus monticola, the tropical 

 American Pinus heteropliylla, Pinus sylvestris 19 of northern Europe and Asia, Pinus Laricio 20 of 

 southern Europe, the Himalayan Pinus JSTepalensls, 21 and the eastern Asiatic Pinus Thunbergii 22 and 

 Pinus densijlora? 3 Resin from which turpentine is distilled is obtained by drawing off the juices of 

 several species, the largest part of the world's supply being obtained from the eastern American Pinus 

 palustrls and Pinus heterop)hylla ; it is also obtained from Pinus Pinaster 24 and Pinus Halepensis ^ 

 of the Mediterranean basin, and from the Himalayan Pinus Roxburghli™ Tar 27 is manufactured 

 by the slow combustion of the wood of Pines and other conifers. Oil of turpentine 28 and other 

 products distilled from the resins of several species of Pinus are stimulant, diuretic, and anthelmintic, 

 and are employed in the treatment of human diseases, 29 and for illuminating purposes. Rosin, the 

 residue left from the distillation of turpentine from resin, is used in plasters, and in the manufacture 

 of soap, sealing-wax, varnish, and cement ; 30 and an essential oil used medicinally is distilled from 

 the leaves and young shoots of different Pine-trees. 31 The large slightly resinous edible seeds of 

 several species are important articles of human food, the best being produced by the Nut Pines of 

 western North America, by Pinus Plnea 32 of the Mediterranean region, Pinus Cemhra 33 of Europe 

 and Asia, and Pinus Gerardiana 3i of northwestern India. Pine wool, a coarse fibre manufactured 

 from the leaves of Pinus Laricio, Pinus sylvestris, and other European species, is used to stuff mat- 

 tresses and cushions, and, woven with animal wool, is made into hospital and military blankets and 

 into underclothing which is believed to possess valuable medical properties. 3 ^ In the southern United 

 States coarse carpets are woven from the leaves of Pinus palustrls. 36 In China different species of 

 Pinus are used in medicine. 37 The bark of several species contains sufficient tannic acid to make them 

 valuable for tanning leather, and in the Old World Pine-bark is occasionally employed for this 

 purpose. 3S 



The cultivation of Pine-trees for the production of timber has long occupied the attention of 

 Japanese 39 and European silviculturists ; and Pine-trees are used to decorate the parks and gardens of 

 all temperate countries. 



In the United States Pinus is preyed on by many insects, 40 and is attacked by numerous fungal 

 diseases. 41 



Pine-trees can be easily raised from seeds, which, however, must not be allowed to become dry, as 

 they soon lose their vitality. Easily transplanted while young, their long fibrous rootlets do not hold 

 the soil firmly when disturbed, and make the operation of moving large plants difficult and uncertain. 



The classical name of the Pine-tree was adopted by Tournefort 42 for this genus as it is now 

 limited. 



