SALICACEAE 



Populus acuminata , Lanceleaf Cottonwood, This poplar is less 

 common in cultivation then many others, Pfooton C: Standi ey in their 

 "Pi or a of Nov: Mexico" recommend it for ornamental and street plant- 

 ing , 



Populus I acDougalii , the PacDougal Poplar, and Populus 

 w isliscni i, the ITislizen Poplar, are used in the southern part of 

 our range for ornamental and shade trees, 



Populus alba, the Silver-leafed Poplar, is far from popular 

 in many "places •* TE will grow almost any place where even a little 

 moisture is assured and proceeds to make thickets in lawns and 

 meadows and becomes very difficult to eradicate. The beauty of the 

 tree and its value as an erosion control agent cannot be questioned. 

 It should not, however, be planted without due thought of the conse- 

 quences. It is not indigenous to the southwest but has been planted 

 in many places and has escaped. 



P opulus a ngus t if ol ia , the Harrow- leafed Cottonwood, is prob- 

 ably more suitable for planting along streams than any of our other 

 cottonwoods. It is abundant along mountain streams fro:: Central 

 Arizona and Hew Mexico tc the far north, - It grows readily from cut- 

 tings and while small, furnishes much browse for cows and horses. 



Populus sargonti i, Cottonwood, The use of the broad-leafed 

 poplar in our erosion control program should always be limited to 

 sites where there is no reason to conserve moisture and to places 

 whore a quick shade is especially desirable. A bottom filled with 

 cottonwoods is likely to be streanloss, for the moisture required 

 to supply a large cottonwood will water a much larger area of grass 

 and quench the thirst of a few cows also. Cottonwoods are not very 

 good erosion control plants for they wash out too easily and tend 

 to divert water courses to new channels, ".Pillows, especially small 

 ones, form much greater masses of roots and bend downstream at flood 

 times instead of being uprooted. 



The Sargent Cottonwood, common to southern Colorado and 

 northern Nov/ r'cxico, grows readily Prow, cuttings and is a fast 

 growing tree suitable for planting about dwellings* 



Salix nigr a, or the cor' ion Black Willow, is probably our 

 most effective tree as a soil binder along streams. It forms small 

 roots in such abundance that erosion is largely or completely 

 stopped. This can hardly be spoken of as an overlooked plant as 

 it has probably boon used more than any other tree in this region. 

 The disadvantage of this tree is that it is practically worthless 

 for other purposes; 'when it grows to any size the forage value is 

 gone; and the wood is not suitable for posts or even firewood. 



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