378 Journal of Agrlcidture . Victoria. [10 June, 191 i. 



not to give an excess of potash, as that manure given in excess tends to 

 thicken and toughen the rind, as well as to increase the acid quality of 

 the fruit. Nitrogen is the greatest necessity of citrus trees, and a cover 

 crop of some leguminous plant will always benefit the citrus orchard. 



Well rotted .stable manure is always valuable and helpful, particularly 

 i"^ it is collected and stored so as to retain the urine as well as the solid 

 manure. In sandy soils, stable manure, by adding humus to the general 

 mass, is probably the best manure. As a stimulant, nothing is more suc- 

 cessful than sulphate of iron, applied at the rate of from i lb. to 2 lbs. 

 per tree. It may be dissolved in 10 gallons of water, and thus fed to the 

 roots, or it may be scattered broadcast between the trees before an irriga- 

 tion, subsequently ploughing or cultivating the soil. A top dressing with 

 new soil, sand, leaf mould, gutter or drain washings, and vegetable refuse 

 matter of any kind will always be helpful as plant food in the citrus 

 plantation. 



{To be continued.) 



SPRAYING FOR IRISH BLKxHT. 



D. McAlpine, Vegetable Pathologist. 



The efficacy of spraying is no longer called in question bv any one 

 who has given it a fair trial, but for those who have lost their potato crops 

 during the past season, the following facts should convince them that it 

 pays to spray, apart altogether from the increased yields. 



In the minds of many, the weather is the controlling factor ; but. during 

 this season, which has been the worst on record for the eiicouragement of 

 fungus diseases, the results obtained both with " Black Spot " of the apple 

 and " Irish Blight" of the potato, proved conclusively that spraying done 

 thoroughly at the proper time and with the proper mixture saves the crop 

 in spite of the weather. 



1. The following letter has just been received bv the Department from 

 a large potato-grower : — • 



Adverting to our previous corres'^onleuce, I desire to sa\' that I sprayed my 

 potatoes again about the beginning of March, and, although I have blight on my 

 farm, the sprayed potatoes are remarkably free from it. I have just dug 100 bags, 

 and there was not i per cent, infected; another paddock spraved twice is practi- 

 cally clean, and a strip not five chains away — a few rows that I did not spray — is 

 completely rotten. 



The disease in this district is in a most virulent form ; a series of hot, misty 

 muggy spells made a heart-breaking mess of things. The disease appeared simul- 

 taneously over a very large area, hardlv missing a farm, and leaving ruin every- 

 where. I used a 2 per cent, solution of bluestone with soda and a high-pressure — 

 140 lbs. to the square inch — to which I attribute my success. I do not think the last 

 word has been said in the matter of spr.iv pumps. The ])umps driven off the axle 

 seem to lack the necessary power, and T consider a motor an essential. Spraying 

 has failed in a good many Instances here, but I know a good many have only 

 sprayed as a matter of form. It does not seem any good monkeying with Irish 

 Blight. It is a most insidious foe, and we must fight it with the gloves off, but 

 I have seen enough to convince me that Bordeaux — if applieri strong enou'^h, and 

 with sufficient force — will, at least, take the sting out of it. Personally, I would 

 like to see spraying made compulsory, but I do not see how it could be done very 

 well. 



2. The good effects of spraying, even when done rather late in the 

 season, was shown in the experimental plots at Kardella conducted by 

 the Department. Over one acre of newly broken up land was planted wdth 

 seed potatoes which had been sent to the destructor, and were very badly 



