656 



Agricultural Gazette of N.S.W. 



[Sept. 2, 1920. 



conditions of culture, or under irrigation, makes it imperative that a system 

 allowing of full development of the vine shall be adopted. Thus we find 

 that there is a tendency to resort to double- and treble-decked modifications 

 in order to curb the vigour of this particular vine. 



Whether such a practice is the best in the long run is questionable. The 

 simpler the construction of the vine the better the ultimate results, and 

 if this strength of the vine will warrant say 12 feet of main arm well 

 furnished with secondary arms, it is better to have this built up all on the 

 same level than to have the vines half the distance apart with double-decked 

 arms. The only point to be considered is that the one arm may take longer 

 to build up. 



The same systems may be applied to strong-growing table grapes in rich 

 soil. It is at times asserted that the long arms have been a failure, but 

 when this has been so it will usually be found that the failure is the result 

 of one of two faults in construction. 



Fig. 14. — The Thomery Spaller, spur-pruned. 



Firstly, there is a great tendency to extend the arms too quickly from 

 year to year, resulting in an excessive number of buds to be nourished. It 

 then happens that the individual growths from these buds are very weak, or 

 else that a portion of them fail to burst, leaving a poorly-furnished arm. 

 The secret of successful formation lies in the establishment of a stout arm, 

 liberally furnished with strong, vigorous canes to start the secondary arms. 

 None but a strong cane should be used to start a main arm, and it should be 

 so extended that all the buds will give rise to good-sizetl canes. 



The second mistake lies in extending the length of the arm to such a limit 

 that it overtaxes the ability of the root system to nourish the amount of 

 wood and fruit which it is capable of carrying. This is a common trouble 

 in vines of only ordinary vigour. The trouble becomes accentuated when 

 the sun, through lack of foliage, dries up the main arm, interrupting the free 

 flow of the sap. Weak or dead secondary arms ultimately arise, and 

 frequently nature asserts itself in forcing numerous water shoots from the 

 stem or other healthy portions of the vine. 



For these conditions modifiefl forms of the systems are used, having, as a 

 rule, short main arms, upon which the fruiting wood is renewed from year to 

 year in the form of spurs and rods. 



