157 



to drop at various stages, either when they first appear after push- 

 ing out from the sheath or even when they are nearly full-grown. 



The disease extends from the flower bud along the stalk of the 

 adjacent leaf, causing it to turn a yellow colour, and spreads along 

 the stem itself, until finally it reaches the "cabbage" and kills the 

 tree. 



Although bacteria have been found in great numbers in diseased 

 spots, it is not yet decided whether they constitute the disease it- 

 self, or whether they are only the accompaniment of another 

 disease. 



But the practical point is that by means of experiments which 

 have now been carried on for some time, it has been shown that 

 this disease can be checked by two methods. One plan is to fire 

 the tree by putting a light to the fibrous material, the so-called 

 " strainer," at the base of the leaves during dry weather. The fii'e 

 burns the leaves, and scorches all the tender parts, killing the 

 disease. 



Another plan is to spray the head thoroughly with Bordeaux 

 mixture. Several instances can be pointed- out where trees have 

 been sprayed, and are now healthy-looking and are holding their 

 nuts. It is advisable, however, to spray diseased trees every six 

 months, for say two years, as a prevention against its breaking 

 out again. 



Firing a tree is the easier method, and there is no expense for 

 spray pump and for the Bordeaux mixture : but the leaves have 

 been burnt, and it will take about two years before any fruit is 

 obtained. If the average annual crop is worth 4s., this delay 

 means a loss of 8s. a tree. 



The expense of the Bordeax mixture and its application is esti- 

 mated to cost about 2d. a tree, without counting the cost of the 

 spray pump. 



The spray pump can be worked by two boys, one to climb the 

 tree, and point the nozzle at the end of the hose downwards all 

 round the head, while the other works the pump. 



When the cabbage is rotten, or when a tree dies, it should be 

 cut down, and the head with its leaves should be thoroughly 

 burnt, otherwise it remains a source of infection to other trees, not 

 only in the neighbourhood, but probably for long distances round. 



BORDEAUX MIXTURE. 



Bordeaux mixture is best made according to the following for- 

 mula : — 



Blue Stone (Copper Sulphate) 6 pounds 

 Unslacked Lime 4 pounds 



Water 50 gallons 



It requires careful mixing, or the ingredients will not combine 

 properly. Put 25 gallons of water into a barrel. Tie up 6 pounds 

 of copper sulphate in a piece of coarse sack, and hang this by a 

 stick laid across the top of the barrel so as to be just beneath the 

 surface of the water until it has slowly dissolved. 



