259 



{Tsuga heterophylla) , giant red cedar {Thuja plicata) and wliitc fir 

 {Abies grandis). The injury to the Douglas fir was most striking 

 in logged-off or burned-over areas where there was an almost pure 

 stand of young trees from lo to 25 years old. The height of 

 young trees of this species is on the average a little over one 

 foot for each year of their age. Many of these young trees had 

 never before borne any weight of snow at all approximating the 

 weight that rested upon them during this winter. Where they 

 grew in a dense stand the accumulated masses of snow frequently 

 uprooted or broke down a number of trees together. Some of 

 these clusters of trees fell at once to the ground while others 

 remained supported for a time by other vegetation which in 

 many cases they finally broke. The writer has not seen any 

 case of injury to conifers occurring singly in the open. The 

 writer has not found any injury of consequence to younger 

 conifers less than 6 feet high, even where they occurred in dense 

 stands in the open. The species examined under these conditions 

 are Douglas fir, lodge pole pine {Pinus contorta) and western 

 white pine {Pinus monticola) . 



The region observed by the writer includes the campus of the 

 University of Washington, other places in Seattle and the im- 

 mediate vicinity, the Cedar River valley east of Seattle, and 

 various points in Kitsap county, Washington in the vicinity of 

 Silverdale, Seabeck, Crosby and Chico. 



Several of the trails on the uncleared portion of the campus 

 of the university were rendered impassable b^^ the fall of young 

 conifers during this snow. The same was true of trails and even 

 of roads in Kitsap county. 



Considering the large number of species of broad-leaf ever- 

 greens in the regions and the great abundance of individuals of 

 some of these species in certain places it was a matter of surprise 

 to find practically no mechanical injury to them from the snow. 

 The Madrona is the largest of these and is also the most abundant 

 in the regions observed by the writer. The others observed, such 

 as stick}^ balm and manzanita {A rctostaphylos tomentosa) are more 

 in the nature of shrubs. 



The most striking fact observed about snow injury to trees 



