148 President's Address. 



has resulted in great pecuniary losses to nurserymen, as 

 well as to the vexatious disappointments of plant growers, 

 it must be kept in mind that such unwelcome results are 

 not dependent in the case of any individual plant on the 

 mere fall of the temperature to a stated or even an 

 approximate low point, but that the amount of injury 

 sustained by the said plant is largely dependent on the 

 influence which the previous growing season may have 

 had upon the maturation or non-maturation of its growth. 

 Thus the Lombardy poplars around Edinburgh and in 

 other districts were either killed or irrecoverably injured to 

 an extent formerly unknown by the slightly above zero 

 temperature of December 1879, happening after an un- 

 precedentedly late and unfavourable autumn for perfecting 

 their growths, although in previous seasons they had 

 endured fully as low temperature without injury ; and 

 although extensively grown in America they do not there 

 suffer from the much greater intensity of the winters. 

 Again, orchard or standard peach trees that have had their 

 annual growths ripened or matured by the summer and 

 autumn warmths of Canada and the Northern United 

 States retain perfect health and fertility, although the 

 winter temperature is often 30° below zero, while it is only 

 in a few of the most favoured Scotch gardens that they are 

 occasionally so far matured on the warmest southerly 

 exposed garden walls, as to withstand our winters and 

 produce fair crops of fruit. 



IV. Plants that take less time than others to mature 

 their Growths. — It is a generally known as well as an 

 easily confirmed fact, that plants of the same species 

 which expand their buds earliest often do not mature their 

 autumn growths earlier, or even so early as others which 

 do not put forth their young leaves till all chance of 

 injury from late spring frosts is past. Orchard ists and 

 horticulturists are familiar with the fact that varieties of 

 pears and apples {Pyrus communis and P. 3Ialus), as well 

 as of other fruit trees which are latest in budding and 

 blooming, are often the best growers as well as the most 

 regular bearers ; and that kinds which ripen their fruit 

 comparatively early frequently continue growing so late in 

 autumn that their young shoots, as well as their blossom 



