196 OUR FORESTS AND WOODLANDS 



cultivation of poplars, but none of the good 

 kind will thrive to the best profit on dry, 

 high-lying land. Given those favourable condi- 

 tions, the Canadian poplar is the species whose 

 cultivation is most likely to yield good and profit- 

 able returns. It is hardy, and shows itself more 

 accommodating with regard to soil than either of 

 the other two kinds; while it is extremely rapid 

 in growth, produces wood of better quality than 

 the common black poplar or the abele, and can, 

 though essentially a light - demanding tree, be 

 grown somewhat closer together than either of 

 these. These advantages can perhaps best be 

 estimated when it is recollected that even the 

 common black poplar often yields an average of 

 two feet per tree per annum at thirty years of age 

 when grown in a free position. Though this 

 growth would, of course, be less in highwoods, 

 yet the quality of the cleaner timber would be 

 better for all kinds of technical purposes. The 

 white poplar is somewhat more exacting than 

 either of the black poplars as to the kind of soil 

 upon which it grows. It thrives best on loamy 

 or sandy land ; on anything like stiff" clay soils it 

 is apt to become dry in the top. Though it 



