THE WILLOWS OF OHIO. 303 



Salix petiolaris Smith. Slender Willow. 



A shrub very similar to Salix sericea in habit. But typical 

 leaves are quite different from those of that species in general 

 appearance. Unfortunately, however, in this region connecting 

 forms sometimes render it impossible to distinguish the two from 

 the leaves alone. They are rather narrower, margin (sometimes 

 entire) serrate with more prominent, blunt cartilaginous teeth, 

 subglossy above, quite glaucous beneath, or sericeate when young 

 oftenest with ferruginous hair, venation so similar to that of 5. 

 sericea that it cannot be distinguished unless by the more ascend- 

 ing primaries and the finer reticulations. Carpellate aments 

 short peduncled, becoming somewhat lax in fruit, scales yellow, 

 mostly darkened above, pilose, capsules long pedicelled, acutish, 

 in fruit cylindric conic, more than 4 mm. long. 



The character of the leaves in the extreme form is very simi- 

 lar to that of the Broad-leaved Willow with which they might 

 be confused were it not for their narrowness. The difficulty in 

 separating them from S. sericea comes especially late in the sea- 

 son when that species begins to lose its pubescence and to become 

 more glossy on the upper surface. The catkins sometimes re- 

 semble those of Salix bebbiana but can be distinguished by the 

 darkened rather than yellow scales. With these exceptions the 

 present species is not likely to be confused with any other in our 

 area. 



Salix petiolaris is the western form of Salix sericea or rather 

 since that species was later named, it is the eastern form of 5. 

 petiolaris of which it was made a variety by Andersson. It almost 

 seems as though that were the proper treatment and that we 

 should be doing well to return to Andersson's view but the carpel- 

 late aments seem fairly distinct. 



? T We are near the eastern border of the range of Salix petio- 

 laris. It occurs rather rarely in Ohio and has been found only in 

 the north-western portion of the state, though it may extend well 

 eastward along the lake shore. 



Salix petiolaris gracilis Anders. Frequently one meets with 

 forms of the Slender Willow with even more slender and graceful 

 twigs than the usual form. This variety has been given the name 

 gracilis bv Andersson. It is characterized by narrower, more 

 sharply serrate leaves and longer pedicels than the typical form. 

 It may perhaps be taken as the extreme development of the 

 type farthest from 5. sericea. It is to be expected wherever 5. 

 petiolaris is found. 



