

BY E. IIAVILAND, F.L.S. 175 



As to any remedy, or means of destroying the fungus, when once 

 in the plant, I know of none of any real value. As the mycelium 

 of Oidium does not as a rule penetrate the leaf, but confines its 

 destructive power to the surface, it would appear easy enough to 

 get rid of it, and perhaps to a certain extent and in the case of a 

 single plant or so in a garden, this may be done ; but to the farmer, 

 the value of a remedy would consist only in its beiug applicable to 

 crops on a large scale. In many cases amongst our small farmers 

 the loss of a crop, even of pumpkins, is severely felt, especially as 

 at this time, when their chief product, the maize, has been destroyed 

 also. I think, however, that in all cases of disease likely to attack 

 field crops, immunity must be sought rather in preventive measures. 

 More careful drainage, and irrigation where possible ; especially 

 avoiding the repeated planting of the same ground with the same 

 crop ; and generally endeavouring to ensure vigorous plants ; for 

 it may be considered almost an established fact, that fungoid 

 diseases rarely attack strong healthy growing plants. 



Dr. Carpenter in his " Vegetable Physiology" speaking of the 

 spores of micro-fungi says : "It may be considered as certain, that 

 an admixture of the spores of any of these fungi with the corn- 

 grains will endanger the plants raised from them ; but it is equally 

 certain, that the fungi have little tendency to develope themselves 

 in plants that are vegetating with perfect heal thf illness." In 

 another place speaking of Peronospora infestans (commonly known 

 as the "potato disease ") he says, "Just as the yeast plant will not 

 vegetate, save in a fermentable fluid ; so does it seem probable, on 

 consideration of all the phenomena of the potato and vine diseases, 

 that neither the Peronospora of the one, nor the Oidium of the 

 other, will vegetate in perfectly healthy plants." Perhaps it would 

 be well if our farmers in this colony, would take hold of the fact, 

 that it is the opinion of the highest authorities and of practical 

 farmers, both in Europe and America, that careful cultivation will 

 produce plants of such vigour as may be almost considered proof 

 against the attack of these fungoid parasites. 



