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Handbook of Nature-Study 



within it are perfectly adjusted one to another in cylindrical form. The 

 sheath is made up of several layers, one over the other, and may be pulled 

 apart. The new leaves are borne on the new, pale green wood. 



The uses of pines are many. The lumber of many of the species, es- 

 pecially that of the white pine, is free from knots and is used for almost 

 everything from house-building to masts for ships. In the Southern States, 

 the long-leafed pines -are tapped for resin, which is not the sap of the tree, as 

 is generally supposed. Pine sap is like other sap ; the resin is a product of 

 certain glands of the tree, and is of great use to it in closing wounds and 

 thus keeping out the spores of destructive fungi. It is this effort of the 

 tree to heal its wounds that makes it pour resin into the cuts made by the 

 turpentine gatherers. This resin is taken to a distillery, where the turpen- 

 tine is given off as a vapor and condensed in a coiled tube which is kept cold. 

 What is left is known as "rosin." 



The mountain pine of the Sierras. 



This species stands upright normally and is often over one hundred feet high; but on the mountain 



tops, exposed to wind and snow, its trunk reclines on the ground and its branches look like 



shrubs, as shown in the foreground. Trees of the same species, wind-beaten 



but standing are shown in the background. 

 Photo by G. K. Gilbert. Courtesy of the U. S. Geological Survey. 



LESSON CCII 

 THE PINE 



Leading thought The pines are among our most ancient trees. Their 

 foliage is evergreen but is shed gradually. The pollen-bearing and the 

 seed-bearing flowers are separate on the tree. The seeds are winged and 

 are developed in cones. 



