the logged lands. Fire on these areas is of the hottest character, and 

 once started is extremely difficult and often almost impossible to check. 

 Not only is the forest threatened, but also the camps, railroad, and 

 mills of the company, and even the town of McCloud itself. That the 

 frequency and danger of fires is not exaggerated is shown by the fact 

 that in 1903 the company expended $3,000 in fighting fire, and in 1904 

 $2,500. 



CAUSES. 



The causes of fire are manifold. Where the danger is as great as at 

 McCloud the most trivial carelessness is often sufficient to start a 

 serious conflagration. Unextinguished camp fires and sparks from 

 donkey engines or logging locomotives of the company are the com- 

 monest sources from which fires start. 



EFFECT ON THE FOREST. 



The effect of fire on virgin timber is not always at once apparent. 

 The mature trees, particularly yellow pine, are well adapted to resist- 

 ing the effect of an ordinary ground fire, and apparently its chief effect 

 upon the forest is the destruction of brush and litter. In reality, 

 however, the trees are often seriously injured, particularly where fires 

 follow one another at short intervals. Growth is checked and the 

 trees are weakened; and insect attacks and fungous diseases follow. 

 In addition the trees are gradually eaten through at the base, and 

 eventually die or are blown over. Openings thus made in the forest 

 are effectually prevented by subsequent fires from coming up to 

 young growth, while the chaparral, which sprouts from the roots and 

 is not permanently eliminated, even though completely burned back, 

 takes possession of the ground. On the cut-over lands the effect of 

 fire is even worse. Here, because of the greater accumulation of 

 debris, the fire is hotter, and the trees left after lumbering are more 

 likely to be killed. If this goes on long enough, the entire area 

 becomes a chaparral field, and in the absence of seed trees, little chance 

 is left of a return of the forest. 



REASONS FOR PROTECTION. 



To be effective, fire protection entails the expenditure of money, 

 and to warrant this the returns should be commensurate with the cost. 

 For the purpose of demonstrating this, about 15,000 acres in town- 

 ships 39 and 40 north, range 2 west, were set aside as an experimental 

 area. Most of the area had been cut over, and for this reason it was 

 chosen, since not only is cut-over land most likely to be burned, but on 

 it the returns from protection are least apparent. 



The area was carefully cruised, and the stand of timber left after 

 logging ascertained. Growth figures were then taken to show the 



[Cir. 79.] 



