482 ANNUAL REPORT SMITHSONIAN INSTITUTION, 19 63 



for a few minutes to a few clays, and the plants must be hardy enough 

 to withstand such chilling cloaks (pi. 7). 



SnoAv does accumulate, of course, in sheltered places and slight 

 depressions, where it will linger, depending on its depth, well into the 

 summer season and much beyond the general snow cover, which dis- 

 appears almost overnight once thawing begins. On river flats and 

 flood plains large fields of ice will accumulate {Aufeis) and persist 

 sometimes well into August or even until new ice begins to form. I 

 remember particularly such a large icefield along the outlet of Old 

 John Lake, in the Brooks Eange of eastern Alaska, back in 1957, 

 which was still very extensive in early August. Here, at the southern 

 limit of the Arctic, pussy willoAvs {Salix alaxensis (Anderss.) Gov.) 

 and the early spring purple saxifrage (pi. 5) were just bursting into 

 flower in the wake of the retreating ice, in effect just emerging from 

 winter even though the calendar said summer was about over for the 

 Arctic. The immediate environs of a lingering snowbed or icefield 

 are always choice spots for visiting botanists to find; such a spot is 

 usually a mecca for late-bloommg stragglers of many species that have 

 long since gone to fruit elsewhere. 



There are basically two types of sno^v accumulations : the snoiobed 

 (or snowbank, icefield) and the S7wwpatch. Snowbeds form in large 

 depressions or on leeward slopes and usually are several to many 

 feet deep at peak accumulation. Seasonal snowbeds are common sights 

 both in arctic and alpine situations, but they are particularly familiar 

 to many of us in the Alpine (pi. G). As a snowbed melts, it creates 

 a saturated flush area along the lower margins, where plants emerg- 

 ing from the overburden of snow quickly burst into flower. With 

 increasing radius from the snowbed, the stage of development becomes 

 later and later, so that within a snowflush area one can usually find 

 a given species in all stages of development from bud to fruit. Be- 

 cause of the abundant and steady water supply snowflush areas gen- 

 erally support rather luxuriant herbmats, but the species must be 

 adapted for cold soil temperatures, caused by the meltwater, and very 

 short growing seasons. Obviously, a plant that does not emerge from 

 under the snow until mid or late summer has got to go through its 

 reproductive cycle in high gear. 



Snowpatches are relatively small and shallow accmnulations in 

 slight tundra depressions, which melt very rapidly in the spring only 

 a little behind the general snow^ cover. They leave saturated soil 

 patches in which lush turf or herbmat develops. These patches 

 stand out conspicuously from the surrounding drier areas. 



The Arctic suggests glaciers to many, yet glaciers are a relatively 

 insignificant factor to plants in the present-day Arctic as a whole. 

 Except in Greenland and in parts of the Arctic Archipelago, the 



