Hydrology 



Much of the annual precipitation falling on the Line Creek 

 Plateau occurs as snow. Snow tends to be blown free of windward 

 slopes and deposited on the lee side of ridges. The resultant 

 differential snowpack is important in structuring the mosaic of 

 plant communities in the alpine zone. Seep areas tend to form in 

 shoulder positions below snow deposition areas at the very heads 

 of drainages before they fall from the plateau into the canyons 

 dissecting it. These seep areas harbor some of the rare plants 

 found on the plateau. There are two alpine lakes in the study 

 area at the west end of the Line Creek Plateau. Line Lake occurs 

 in a cirque at the head of the North Fork of Line Creek, and an 

 unnamed lake (mainly in Wyoming) occurs in a cirque at the head 

 of Wyoming Creek. 



There are no permanently flowing streams above 9,600 ft. 

 Most water from the alpine zone flows through boulder fields 

 underlying the soil and beneath talus slopes to reappear in the 

 major streams formed in the canyons that dissect the margins of 

 the plateau. Wyoming Creek on the west margin of the Line Creek 

 Plateau and Rock Creek are glacially carved valleys. Other 

 streams fall off steeply to the montane zone and the margins of 

 the study area. There are small calcareous seep areas along the 

 base of the limestone scarp face near North Line Creek. 



Climate 



There are no permanent weather stations on the Line Creek 

 Plateau or above timberline in the Beartooth Mountains. During 

 the growing seasons of 1958 and 1959, mean temperature near the 

 west edge of the Line Creek Plateau was ca . 47° F with the lowest 

 temperature of 24° F and the highest temperature of 68° F (Johnson 

 and Billings 1962). Average weekly precipitation was 0.3 in. 

 Prevailing winds are from the west. While the main portion of 

 the range receives ca. 70 in annual precipitation (USDA-SCS 

 1981) . However, the Line Creek Plateau receives an average of 40 

 in because it is in the rain shadow of the main massif. 

 Consequently the Line Creek Plateau is drier and warmer with 

 earlier snow-release than other plateaus in the range. 



Red Lodge, the weather recording station closest to the Line 

 Creek Plateau is at 5,575 ft and ca. 13 miles northeast of the 

 study area. From 1950 to 1980, mean July and January temperature 

 was 64.9° and 21.8°, and mean annual precipitation was 25.0 in. 

 Wettest months were April, May and June (NOAA 1982). 



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