52 THE NATIONAL PARK SERVICE 



that will withstand the wear and tear of the elements. 



The Service, with the cooperation of the Smithsonian In- 

 stitution, also regulates the excavating and study of the ruins 

 by legitimately interested persons and institutions. It also 

 is gradually performing considerable work in excavation of 

 the ruins along its own lines. 



Forests and Plants. Protection of the forests and of the 

 plant life of the parks constitutes one of the largest problems 

 of the National Park Service, and a large part of the work 

 of the ranger forces, especially during the dry months, which 

 coincide with the tourist season and consequently with the 

 season of camp fires, is directed toward this end. Fire is the 

 greatest menace. It is guarded against by a strict supervi- 

 sion of camp fires, constant patrolling, frequently along strate- 

 gically constructed fire trails, and observation from elevated 

 stations connected by telephone with headquarters and with 

 ranger stations. Close cooperation is maintained with the 

 Forest Service in this connection, national forests adjoining 

 most of the larger parks. The Service has long urged the 

 appropriation of a large fund for use in fire emergencies, 

 $100,000 being suggested to the Appropriations Committee 

 by the Director at the 1920 hearings. In the act of March 

 4, 1921 (41 Stat. L., 1406) $25,000 was appropriated for that 

 purpose, with the proviso that it be not used precautionarily 

 and only after the expenditure has actually been incurred. 



Live stock is a lesser menace to the forest and plant life, but 

 the ranger forces exercise a strict supervision over the grazing 

 of such herds as are permitted to enter any of the parks. All 

 grazing is forbidden in the Yellowstone. Cattle, but not 

 sheep, are allowed to graze in the other parks upon special 

 permit from the Secretary of the Interior. Once in the parks 

 they are kept by the ranger forces in certain designated areas. 

 Constant watchfulness is also maintained by the ranger and 

 scientific forces to detect trees which have become infected with 

 insect parasites, thus constituting a menace to the surrounding 

 timber. The general policy is to remove no timber, but some- 



