THREE THOUSAND A MILE 13 



necessary wood supply. In the past more emphasis 

 has been laid upon the cost of cutting ties than upon 

 growing them. This attitude will have to be 

 changed. It takes an oak tree at least sixty years 

 to attain sufficient size to make four or five stand- 

 ard ties, while many of the trees now used are well 

 over a century old. It may be readily estimated 

 that the present rate of consumption by our rail- 

 roads attains the figure of four ties per second, or 

 in other words these roads consume in one second 

 what it has taken almost a century to produce. To 

 grow oak trees for railroad ties, therefore, is not a 

 proposition that will prove of general interest. 

 Pine and fir trees, however, will reach a size suitable 

 for tie manufacture in twenty to fifty years. 



To plant a crop of trees and harvest them at 

 maturity represents in this country a practically new 

 field, but those who are sufficiently far-sighted to 

 see beyond the next generation regard it as the only 

 means of maintaining the supply of wood absolutely 

 necessary to railroad transportation. Some years 

 ago the Pennsylvania system carried on extensive 

 tree planting along its right of way, but unfor- 

 tunately for the advancement of the idea the wrong 

 species were used and the results were for the most 

 part unsatisfactory. Let us assume that a pine tree 

 capable of producing five ties could be grown in 



