129 



For several years after 1860 I noticed changes in the volume of water 

 in the streams. Since 1870 1 have observed that a large growth of 

 Pine and Poplar clothes the burned surface of the mountains on Bear 

 and Clear Creeks, thus rendering sudden floods less violent than for- 

 merly. Since 1879 Clear Creek has had a more steady flow. I gauged 

 that creek very closely from 18G0 to 1872. I think the water supply in 

 the months of August, September, and October of those years de- 

 creased. This was due, I think, to mining and the clearing of timber. 

 Since that time a slight increase is perceived. 



LAKE COUNTY. 

 (Area, 420 square miles ; estimated forest area, 200 square miles.; 



This county, of which Leadville is the county seat, is situated at a 

 high elevation in the mountain ranges of central Colorado. Within its 

 borders are a number of small lakes ; and here also are the sources of 

 the Arkansas Eiver. 



The forest lands of the county are mainly on the mountains forming 

 its eastern and western borders. About one-fourth of the forest land 

 is fully stocked, good for timber; one-fourth is brush of promising 

 growth, and the remainder has been made w^aste by burning. Pine and 

 Spruce are the predominant trees. 



Yery destructive forest fires have occurred in this county. After the 

 destruction of the forests there is but little chance for their renewal. 



LA PLATA COUNTY. 

 (Area^ 4,000 square miles; estimated forest area, 1,500 square miles.) 



This county, in southwestern Colorado, is 95 miles in extent from east 

 to west, by 42 from north to south, and is situated on.the southern slope 

 of the San Juan Mountains. Its streams flow southward from fertile 

 valleys, the principal ones being the Piedra, Los Pinos, Florida, Ani- 

 mas, La Plata, Mancos, Montezuma, and Dolores. The elevations are 

 from 4,800 to 14,056 feet above the sea. The general altitude of the ag- 

 ricultural belt is 6,500 feet. The northern part of the county is rugged 

 and broken, but the southern slope, dropping into long mesas and broad 

 valleys, is well adapted to grazing and agriculture. 



The northern and western portions of the county are well timbered. 

 About 65 per cent, of the same is fully stocked j 25 per cent, is brush of 

 promising growth, and the remainder made waste by burning. 



The forest growth is Spruce and Fir, large and abundant, in the 

 mountains ; excellent Pine in the middle belt ; and Cedar and Piiion in 

 the south, interspersed with broad stretches of sage brush. After the 

 destruction of forests, especially when caused by fire, their renewal is 

 very slow. 



The volume of water in the streams of the county has not changed, 

 but high water is higher and low water is lower than formerly, due per- 

 24738— Bull 2—9 



