CONSERVATION AND ITS MEANING 593 



year. Forest fires caused by man's carelessness as well as by lio;ht- 

 ning have laid waste over 12,000,000 acres of forest land in a single 

 year. A forest fire does much more than burn trees, for a severe 

 fire usually destroys the organic material of the forest floor known 

 as duff, thus preventing the growth of new forests for years to come, 

 and in addition, it drives out or kills much wild life. 



Other enemies to forests are parasitic fungi that destroy trees, and 

 various insects which eaf their leaves and tender shoots or bore into 

 the wood. The caterpillars of the gypsy and brown-tail moths are 

 chief agents of destruction in the first category, while various beetles 

 may be listed in the second group. The Engelmann spruce beetle 

 has destroyed millions of feet of timber in the Rocky Mountain region, 

 while the Black Hills beetle has done similar damage in South Dakota. 

 Much damage, too, is done by grazing animals, especially sheep. The 

 recent Taylor Act, which throws the entire 165,000,000 acres of the 

 Public Domain open to cattle and grazing interests, is a serious menace 

 to our forests and wild life. In addition to all of this kind of wastage, 

 if we add that caused through waste in lumbering, at the mills, through 

 nonutilization of by-products, and especially in pulpwood cutting 

 for the paper industry, where millions of small trees are sacrificed, 

 we can see many reasons for a general and more scientific conservation 

 of our forest resources. 



Fortunately this country is beginning to awaken to the need of 

 forest conservation and has numerous agencies both Federal and 

 commercial at work toward this end. Many lumber companies are 

 replanting cut-over areas and selecting with greater care the trees to 

 be lumbered. Forests are being treated as crops to be harvested 

 when ripe. Waste products are being utilized to a greater extent. 

 All sawdust formerly had to be burned, but now alcohol, beaver- 

 board, and other by-products are obtained from this source. Although 

 much bark is used for tanning, still there is wastage here. More 

 and more lumber is being treated each year with creosote or other 

 chemicals as a protection against insects, thus effecting another saving. 

 It is estimated that the treating of railway ties with creosote has re- 

 sulted in an annual saving of around 1 ,500,000,000 board-feet. Much 

 wood was formerly utilized in the making of boxes, for which sub- 

 stitutes are used. The Forest Products Laboratory of the United 

 States Forest Service works upon the various chemical products 

 obtained from wood and has shown a list of uses given on page 594, 

 many of which are still not utilized. The trim of homes has been re- 



