GENERAL INFORMATION 17 



abnormal conditions may be classed under three 

 heads, viz. : — 



1. Discoloration, 



2. Abnormal outgrowths, 



3. Death, 



the two latter of which may, or may not, be pre- 

 ceded by the former. Change in colour, however, 

 may be said to be one of the most frequent results 

 of disease attack ; such change may be reduction 

 ot the natural colour generally, or, what is of more 

 frequent occurrence, the local formation of new 

 colour. 



We see then how important It is that the farmer 

 should train his eye — already quick at observing 

 most things — to detect any change In colour in 

 part, or the whole, of his crop ; for if disease be 

 present, it may still be possible, by applying stimu- 

 lating manures to the soil, or fungicides to the leaf, 

 to mitigate the extent of the attack ; growth of the 

 plants being assisted by the former, and healthy 

 plants protected by the latter. 



Diagnosis of Disease. — Abnormalities of any 

 kind having been noticed In a few or many plants, 

 it is essential that some idea should be formed as 

 to the cause. If preventive measures are to be 

 adopted to limit the extent of the attack, and here 

 comes the farmer's difficulty. A small pocket 

 magnifying glass will often reveal much that is 

 obscure to the naked eye — no student of agri- 



