212 Bulletin 68. 



of Minnesota, in Iowa and the Dakotas, but not long enough any- 

 where in this country to warrant final conclusions. Those who 

 live in locations naturally in timber can hardly understand the 

 importance of the genus, to which these trees belong, to the pio- 

 neers on the wind swept prairies. The ease with which many of 

 them are increased, their rapidity of growth, great hardiness 

 against extremes of heat and cold, excessive moisture, and pro- 

 longed drouth, make them widely sought as pioneer trees in 

 most severe locations, for the formation of wind-breaks and for 

 shade from the scorching sun. 



' ' I would not be understood as recommending the general 

 planting of poplars where our finer deciduous trees readily suc- 

 ceed, but for a strong effect in the shortest time in severe locations 

 they have no rival except the large growing willows, which may 

 generally be used with them to advantage. Among the collec- 

 tion of poplars commonly referred to as of Russian origin, are 

 trees having a great variety in growth and foliage, so that by the 

 judicious use of them alone one can secure very good effects in 

 landscape planting. They are not, however, and never have 

 been, represented as new species, but as hardier forms of species 

 alread}^ introduced into this country, and in the following notes I 

 have grouped the kinds under the several heads where they evi- 

 dently belong, using their nursery or horticultural names. Aside 

 from the few exceptions noted, they are all easily increased 

 from hard wood cuttings made in the fall or spring. 



' ' Angulata Class — Young growth plainly marked with ridges 

 or angles. 



Dudley's Popuhis [properly P. balsanii/era, var. viminalis\ 

 Growth only moderate ; when young rather upright in habit, but 

 somewhat pendulous when old. Our older specimens have been 

 badly injured by leaf rust in dry summers, and on this account I 

 have ceased propagating it. The leaves are broadly lanceolate, 

 very wavy on the edges and the young branches very angular. 



' ' P. betulifolia is probably the same species as P. nigra of the 

 eastern nurseries. It makes a tree that is rather open in habit, 

 inclining to a straight trunk with branches coming out at nearly 

 right angles. The foliage remains bright and fresh even in dry 

 sod laud in severe seasons. It is not especially valuable for tim- 



