606 Journal of Agriculture, Victoria. [15 Oct., 1919. 



RE-PRUNING OF VINES DAMAGED BY FROST, 

 HAIL, ETC. 



F. de Castella, Government ViticuUurist. 



October is the month during which vines are most liable to damage 

 by spring frosts. The means by which these disastrous visitations can 

 be parried, or, at least, mitigated, are well known. Smudge fires 

 judiciously arranged and well timed have often permitted the saving 

 of a considerable part, and sometimes even of the entire yield. In this 

 connexion frost prediction by means of the wet and dry bulb thermo- 

 meter is of the greatest value. Warned of the impending danger at 

 sunset the previous evening, all arrangements can be made for the 

 lighting of the smudges between midnight and sunrise.* 



The measure of success which can attend such palliative steps 

 depends, of course, on the intensity of the frost. Smoke protection, 

 which would be quite effectual in the case of a fall in temperature ta 

 2 or 3 degrees below freezing point, would be useless against a frost of 

 9 or 10 degrees below zero. 



Vines which suffered owing either to lack of precautions or to the 

 extreme severity of the frost, must receive immediate attention. This 

 is necessary, in the first place, in order to insure healthy and well- 

 developed wood for the following winter's pruning, but also for the 

 additional reason that it is often possible by prompt action to insure a 

 crop in substitution for the one which has been destroyed by frost, and 

 during the same season. 



It is not sufficiently recognised that even if the entire crop has been 

 destroyed all is not lost; by means of proper treatment, and especially 

 in the case of a good many varieties of vines, a fair crop may still be 

 relied on. 



The buds of the vine are not single, as they usually appear to be. 

 Of course, obviously double and even triple buds are sometimes to be met 

 with; in these two or three large buds are plainly visible. Even where 

 a bud is to all appearances single, however, it is alwavs accompanied by 

 a varying number (from two to four as a rule) of subsidiary buds, which 

 are so small as not to be apparent, even on careful inspection with the 

 naked eye. These latent buds usually fail to develop ; in the case of 

 damage to the main bud, however, one or more of them will sprout in its 

 place, the largest, which we may term the secondary bud, forms a shoot 

 similar to that produced by the main bud, which often yields fruit.f 

 These shoots are mvich more fruitful with some sorts of vines than with 

 others. Though they never equal the primary cane in this respect, they 

 are capable, in the case of some varieties, of producing half or even three- 

 quartfer crops. Vines of this type present the precious quality of yield- 

 ing, subject to proper treatment, a fair crop, even though the first crop 

 may have been completely destroyed by fro?t. 



It is not, however, a question of fruit alone. The wood for the 

 following season's pruning must also be considered, and the frost- 



• Soe Journal for SUipt.cmber, 1910. A reprint of the article on spring frosts is obtainable on 

 application to thn Department. 



t The remiininc; sub-iirllary bud'', which may for convonionce be termed tertiary bud'!, thouch 

 reallv of th'^ sa ne order as the secondary buds, arc of lesser value. They usually bear no fruit and 

 produce weak canes. Should a reeurrenre of frost destroy the secondary shoots, they develop in their 

 turn and provide wood of a kind for the following winter's pruning. 



