YOSEMITE NATURE NOTES 



Salix spp. 



WILLOWS 

 Willow Family — (Salicaceae) 



Although about fifteen species of 

 willows are native to Yosemite Na- 

 tional Park, where they are found 

 growing from the low foothill zone to 

 the frigid upper slopes of the Sierra 

 peaks within the Arctic-alpine Zone 

 (1), but three species can be consider- 

 ed as attaining tree stature. These 

 are the Pacific willow (Salix lasiandra 

 Benth.), also known as the yellow or 

 western black willow, the red willow 

 (Salix laevigata Bebb.), also known 

 as the polished or smooth willow, 

 and the Scouler willow (Salix scoul- 



eriana Barrett). The first named is 

 perhaps the most common. It can be 

 readily found along the banks of the 

 Merced River in Yosemite Valley (2). 

 This is a difficult group of plants 

 and the person not trained in botany 

 will have difficulty in determining 

 the various species. However, as a 

 group they possess certain well de- 

 fined and readily recognized charac- 

 ters with which most people ore 

 familiar and which can be readily 

 noted even by casual observation. 

 Thus, to most people the identity of 



Typical uillow foliage (Inch squares on background) 



(1) Alpine willow (Salix petrophila caespitosa) is one of the more interesting high altitude 

 plants of Yosemite National Park. It is rarely more than 4-6 inches high and can be found on 

 moist slopes in the vicinity of limberline. 



(2) Three others — the heartleaf willow (Salix cordata), the arroya willow (Salix lasiolepis), 

 and the Hind's or sandbar willow (Salix hindsiana) sometimes assume the stature of tall shrubs 

 cmd may occasionally be regarded as small trees. 



