TREES GROWING IN MOIST SOIL. 115 



sight. Often we then stop and wonder to find it among the 

 hickories and buckeyes : it would seem as though it should 

 find the company of the magnolias and cherry trees more 

 congenial. On moist, wooded slopes, in woods or nearing the 

 banks of streams it grows, and it is hardy as far northward as 

 eastern Massachusetts. It then however becomes a shrub. 



NARROW-LEAVED COTTONWOOD. {Plate LIU.) 

 Pdpulus angustifblia. 



FAMILY SHAPE HEIGHT RANGE TIME OF BLOOM 



Willow. Pyramidal^ slender. 30-65 feet. Dakota westward and to Aprils May. 



Arizona and New Mexico. 



Bark: yellowish green and broken on old trees into broad, flat ridges. 

 Branches : grey. Leaves: simple; alternate; with petioles that are not 

 flattened laterally; lanceolate, or ovate-lanceolate; pointed or blunt at the 

 apex and narrowed or rounded at the base ; finely or coarsely serrate ; yellow- 

 green above, lighter below; the mid-rib yellow; thin. Statu inate catkins : 

 cylindrical. Pistillate ones: from two to four inches long. Capsule: ovate 

 and surrounded by fine soft hairs. 



When the flower-buds of the poplars begin to swell and their 

 colour changes to deeper tints every day, then we feel as 

 though the sleeping spring had indeed awaked. In fact many 

 mistake these early unfolding flowers for the first shimmer of 

 young foliage. But on both the staminate and pistillate trees 

 the catkins lengthen and have satisfactorily settled their little 

 domestic affairs some time before the leaves burst from their 

 silver buds. And in this hastening into bloom there is some- 

 thing of method to be detected. The poplars rely on the wind 

 to carry their pollen from one plant to another and to facilitate 

 its reaching them, the pistillate flowers hang mostly near the 

 tips of the branches. Were the trees fully clothed with foliage 

 it would greatly obstruct the flying pollen and direct it into 

 idle paths. 



When the leaves of Populus angustifolia unfold their out- 

 line is rather a surprise and is seen to resemble that of one of 

 the broad-leaved willows. From their buds exudes abundant 

 balsam. In moist soil and along the banks of streams of the 



