Section IV., 1903 [ 149 ] Trans. R. S. C. 



VIII. — On the Relaiion of Moisture-content to Hardiness, in Apple 



Twigs.^ 



By Frank T. Shutt, M.A., F.I.C., F.C.S., 



Chemist, Dominion Experimental Farms. 

 (Read May 19, 1903), 



For several years past, the writer, associated with the Horticulturist 

 of the Experimental Farm, Mr. W. T. Macoun, has been carrying on a 

 series of experiments in the farm orchards at Ottawa, to ascertain the 

 effect of various methods of cultivation and treatment on the soil's 

 moisture-content at different periods throughout the growing season ; the 

 present research was suggested by certain results obtained in that in- 

 vestigation. 



It has of recent years been generally conceded that the manage- 

 ment of the orchard soil, under ordinary circumstances, should be 

 such as to furnish during the spring and early summer months an abund- 

 ance of moisture for the growth of the tree and the development of 

 its fruit, but tlïat, later in the season, vegetative growth should 

 be checked and the " ripening " of the wood promoted by the with- 

 drawal of excessive moisture from the soil by the growth of a " cover 

 crop." Eegarding this as correct, and in the adoption of any system 

 that (has for its object, or rather for one of its objects, the early 

 ripening of the season's growth, it is obvious that we indorse the view 

 that in the ripening of the wood there is a loss of water from its 

 tissues ; in a word, that ripening may be considered largely as a drying 

 out process, and that those varieties whose growth ripens best (loses 

 most water) will prove the hardiest.^ We should expect to find 



^ This paper is to be regarded merely as a preliminary note. The investi- 

 gation is still being carried on, and, if subsequent results confirm those 

 here recorded, it is proposed to make a fuller presentation of the subject at 

 the next meeting of this Society. 



^ Hardiness, or the ability of the new growth to pass the winter without 

 injury, is a very important consideration when selecting varieties for a com- 

 mercial orchard in a northern latitude. The term, naturally, is a relative 

 one. There are among varieties of apple, well recognized degrees of hardi- 

 ness; and, even for the same variety, the hardiness may vary according 

 to the severity of the winter and possibly certain other factors, e.g., the 

 location of the orchard, the character of the soil and the time in the autumn 

 at which vegetative growth ceases. It is thus seen, that while hardiness 

 may be largely an inherited quality, it is one that may be influenced by 

 environment. 



