568 Agricultural Journal of Victoria. 



neither was the quality of the fruit of American vines improved by 

 grafting on improved varieties of Vinifera. 



Die-back- 



This term, so generally employed to indicate the dying back of 

 branches of fruit trees, is a somewhat unfortunate one. The expres- 

 sion as used in this State embraces the injury resulting from the 

 various fungi which cause "root rot," principally the honey agaric 

 (Armillaria tnelleaj , the symptoms presented by trees attacked by 

 the root borer {Le/ptops hopei), as well as the common failui-e due to 

 unsuitable physical condition of certain soils. As in the first two 

 cases we are able to point to certain parasites as the cause of the 

 trouble it would be more satisfactory if the use of the term " die- 

 back " were restricted to the evils resulting from influences less 

 obvious, such as improper physical conditions of the soil. In this 

 latter connection, referring to the trouble as manifested in the dry 

 climate of California, whei'e fruitgrowing is carried on under irriga- 

 tion, and where the conditions existing are aproximately the same as 

 those in many of the northern districts of this State, Professor E. 

 W. Hilgard, of the California University Experiment Station, 

 makes the following trenchant remarks : — " Few persons outside the 

 Experiment Station can have an idea of the extent to which the 

 planting of orchards on shallow soils underlaid by hard pan or heavy 

 clays has caused pecuniary loss, often almost ruin, to old-timers as 

 well as new-comers to the State. Everj^ few days there comes to us 

 at Berkeley letters transmitting samples of tree branches having the 

 "die-back," and asking about the means of relief. We might 

 usefully stereotype the first letter in reply to such inquiries, briefly to 

 the effect : ' Examine your subsoil ! ' In nine cases out of ten^ it is 

 either the hard pan, or an impervious clay substratum, which deflects 

 the roots sideways after the second or third year, and, of course, 

 prevents a normal development towards the moist depths of the 

 soil, where abundant plant food awaits them in all good orchard 

 lands. More rarely it is a layer of coarse sand, or gravel, which 

 prevents the rise of moisture from below ; sometimes it is the rise of 

 the bottom water which causes the disease of the deeper roots, and 

 also starves the tree. Almost invariably the question is asked : 

 ' What fertiliser must I apply to remedy the trouble ? ' Well in 

 most cases no fertiliser of any kind will remedy the difficulty, the 

 existence of which should have been ascertained before planting the 

 orchard, or, better, before buying the land at all. . . . However 

 important is the presence of ])lant-food ingredients in the soil, the 

 fundamentally needful point is p)roper physical condition without 

 which no amount of fertilization, or natural productiveness is of any 

 avail. All understand the need of moisture ; but unless care is taken 

 to see that it gets where it will do the most good, and that the roots 

 can perform their functions in the depths of the soil, water, work, and 

 fertilisers may alike be wasted." 



