177^ The Trees of Great Britain and Ireland 



Leaves ovate-cordate, nearly as broad as long, 4 to 7 in. long, 3 to 6 in. 

 wide ; pale beneath, with regular serrations except at the base, where they are 

 few and wide apart. i^- H.) 



The Raising of Poplars from Seed 



No good description or illustration of the germination of poplars seems to have 

 been published in England before that of Miss Florence Woolward^ in 1907. 



I have never found in England a poplar grown from seed either naturally or 

 by nurserymen ; and though Grigor ^ describes the process, it seems doubtful whether 

 he ever practised it ; and all my own attempts to raise poplars from seed were fruit- 

 less, until I followed nature as closely as possible. Having observed that poplars 

 only germinated freely on the sandy banks of rivers, I sowed seed as soon as ripe 

 on a pot of sand, and placed the pot in a pan of water in the full sun. Germination 

 was then extremely rapid, according to Miss Woolward, in ten hours to two days. 



1 found that after four days no more seeds came up, and that in all cases the pro- 

 portion of germinating seed was quite small. In five or six days the cotyledons are 

 well developed, but the growth of the young plants is very slow and does not exceed 



2 to 5 inches in height in the first season. Some one-year seedlings of P. nigra, sent 

 me from the banks of the AUier in central France, were only 3 to 4 inches above 

 ground, though their thick rather fleshy root was 6 to 10 inches long. Some seedlings 

 of P. monilifera from the banks of the St. Lawrence in Canada, collected by 

 Mr. Jack, were equally small ; as were some of P. nigra raised by Mr. Hankins from 

 seed collected at Bury St. Edmunds. 



Miss Woolward and I also raised P. canescens from seed collected at Upcot 

 near Colesborne, where both sexes of this tree grow on my own property ; and 

 she raised P. marilandica from seed of a tree in Kew Gardens. In both cases the 

 seedlings were much less vigorous than cuttings from the same trees. 



I also raised seeds collected under a tree, which I believe to be P. monilifera, 

 of American origin, in the botanic garden at Padua, which was perhaps fertilized 

 by a P. alba, the only poplar growing near it ; but none of those seedlings have 

 shown the least sign of hybrid origin, and have grown slowly and seem tender as 

 compared with poplars raised from cuttings. 



I am therefore convinced that, though we may succeed, by crossing different 

 species, in obtaining new races of superior vigour, like P. Eugenei and P. robusta, the 

 raising of poplars from seed is not a practice which can be recommended for general 

 purposes. Some species of poplar are said to be difficult or impossible to strike from 

 cuttings, among which Grigor includes P. alba and P. canescens, but I have found no 

 difficulty in the case of the latter. In the case of species which will not strike, 

 recourse must be had to layers, root-suckers, or grafting. (H. J. E.) 



'^ Journal of Botany, xlv. 417, t. 487 (1907). 

 yrboriculture,jz%^,%%^). Hickel, \t. Bull. Soc. Dend. France, No. 25, p. 88 (,9.2), gives directions for raising 

 poplars from seed, which he has followed with success at Versailles. 



