288 



Plant-Lice on Mangolds. 



[AUG. 



The quantity to be applied per acre is about 120-150 gallons 

 where the foliage is fully developed ; it might be somewhat less 

 in the earlier stages of growth. The plants should be sprayed 

 from underneath, as well as from above, so as to reach the 

 fungus on the under sides of the leaves. Machines can be 

 obtained which spray the plants from below, or which, in other 

 ways, secure that the solution shall reach the lower side of the 

 leaves. 



The cost of a single spraying need not exceed 8s. per acre, 

 .and, with certain horse machines, 30 acres can easily be treated 

 an a day. The operation should be done before any symptoms 

 •of disease show themselves, say towards the end of June or early 

 in July, according to the locality and season. The first spraying 

 should be as soon as there is a good development of haulm, the 

 treatment being repeated about three weeks later, when the 

 growth is complete. If only one spraying is given it should 

 take place about the middle of July. Early blight (leaf curl), 

 which comes in dry seasons when the plant is only a few inches 

 high, should be treated in the same way. 



Complaints have recently reached the Board of considerable 



damage to the mangold crop due to the attack of a small black 



aphis or plant-louse, which lives in colonies 



Plant-Lice on tne un derside of the leaves. Where 

 on Mangolds. , . • 1 , 



a spraying-machine is available the crop 



should be treated with one of the approved washes in use 

 against green-fly, care being taken that the spray is directed 

 upwards, so that it reaches the underside of the leaves. A 

 suitable wash consists of 8 lb. of soft soap in 100 gallons of 

 soft water. To this should be added the extract got by boiling 

 61b. of quassia chips in 2 gallons of water. Instead of the 

 quassia, ii gallons of paraffin may be added to the 100 gallons 

 ■of soap wash, care being taken to thoroughly incorporate it 

 by means of vigorous stirring. These quantities will suffice 

 for one acre, though more may be applied in the case of 

 ,a bad attack. 



