174 DISEASES AND INJURIES TO FOREST TREES. 



by a sudden muscular contraction of tbe parts. It is somewhat difficult 

 to kill, as it seldom comes above tbe surface, but may be poisoned by 

 strycbnine placed in a carrot, an apple, or a potato, and laid in tbe soil at 

 tbe points wbere the burrows come to the surface. It is said to fiud 

 a deadly enemy in tbe little striped skunk. 



Tbe Beaver may be classed among the animals injurious to forests, 

 chiefly from tbe destruction caused by tbe flowing of iutervale lands by 

 building dams. Such " beaver meadows " were common throughout tbe 

 jSTorthern States when first settled, and the areas thus flowed often cov- 

 ered hundreds of acres. This animal has been nearly exterminated by 

 the hunters, excepting in tbe remote forest-regions of tbe Northwest, 

 and in some of tbe swamps of the South. The cypress timber of Vir- 

 ginia is sometimes much injured by tbe beaver, wbicb gnaws down tbe 

 trees to get the young tender buds for food, and considerable destruc- 

 tion is still done by this animal in tbe Western Territories. 



When Deer are shedding their horns, they sometimes damage trees 

 seriously by rubbing off" the bark. For this they select young trees 

 still elastic and yielding. They also injure by eating off tbe young 

 twigs. 



Some injury is done by birds eating off tbe terminal buds of jouug 

 piues and firs. 



DISEASES, AXD OTHER INJURIES TO FOREST TREES. 



Aside from damages done by insects and other forms of animal life, 

 trees are liable to various accidents and injuries, of some of wbicb we 

 can determine the cause, which may be avoidable, while at other times 

 we cannot trace back to the origin of the evil, however sadly we may 

 feel its effects. x\mong the known causes may be mentioned external 

 injuries, want of air and light, stoppage or drainage of waters, chemical 

 ac ion, exhaustion of soil, climatic vicissitudes, and fungus growths. 

 Some of these we will more particularly describe, with such facts con- 

 cerning them as appear most important. 



The most disastrous feature of the timber question in the Rocky 

 Mountain region is, the difficulty with which the forests appear to start 

 when once destroyed, and leit to the natural agencies, wbicb in the tim- 

 ber-growing regions of the Atlantic States would, in a few years, again 

 cover the surface with a luxuriant growth of young forests. Occasion- 

 ally we meet with this effort at renewal in tbe region under notice, but 

 these instances are exceptional rather than common. Professor Hay- 

 den, in his report of 1871 (p. 221), in speaking of this subject, says: 



In travelicfj through the mountain dhtricts, I was surprised at the large number of 

 Imrned streaks that I observed. lu fonie xilaccs we would not travel more than a mile 

 or two without seeing either to the right or left a blackened belt stretching up the 

 mountain side. If these spots would again be covered by a new growth, the result 

 would not be so di?astrou8, but, as has been truly ststed in the quotation (referring to a 

 citation from Mr. Reed's article in the Transactions of the California State Agricultural 

 Society for 1868-'69), this is not the case, for when ouce the forest covering is destroyed, 

 it is never restored, but remains forever bare. Whether this be wholly due to the cli- 

 matic conditions or not I do not know, bu*' there are some reasons to believe that, even 

 where undistuibcd by the hand of m.m, the fonsts are gradually disappearing under 

 the influence of natural causes. The smooth and rounded hills in parts of Wyoming- 

 Utah, Southeastern Idaho, Southirn Montana, and other parts of the Rocky Mountain, 

 region have occasionally, lure and there, a fev/ trees wh'.ch have every appearance of 

 being the remnants of former fon sts. These hills bear unmistakable evide,-co of hav- 

 ing been worn down by the action (f the atmosphere, water, ice, snow, »S:c. The 

 debris which has bet u worn down has covered up the former ruggedness of their decliv- 

 iiieti. * » * But where the original rugged declivity has resisted this action, 

 tlierc, almost invariably, forests will be seen. 1 have theretbre come to the conclusion 

 that tbe forests of the Rocky Mountains, as a general thing, are decreasing from nat- 

 ural causes, and I base my conc'.ubiOLS on the following grounds: 



