194 BOARD OF AGRICULTURE. [Pub. Doc. 



insect life and fungous diseases, and no sooner does a new 

 destructive insect or fungus appear than the scientists con- 

 nected with the stations in the various States vie with each 

 other in throwing search-lights upon every possible phase of 

 the subject, and soon we learn that by providing certain 

 conditions or by the skilful application of certain remedies 

 our crops can be saved. Not only do the station workers 

 learn the best remedy or preventive for insect or fungous 

 pests, but they often, by careful and extended experiments 

 in the field, determine how to apply remedies in the cheapest 

 and most effective way. This is "practice with science." 

 It is hardly possible, however, for the stations, within the 

 limits often available, to always settle these important ques- 

 tions. The practical, wide-awake business farmer, gardener 

 or fruit srrower must take the matter in hand and settle the 

 question as to whether there is any profit in using insecticides 

 or fungicides. 



Our time is limited to-day, and we can only discuss a few 

 of the most important insect and fungous pests, and the 

 application of fungicides and insecticides for their destruc- 

 tion. 



You are all more or less familiar with the history of insect 

 life, and in this discussion no explanation of the terms used 

 will be needed for a full understanding. Insects are gener- 

 ally visible, but fungous diseases cannot be seen by the 

 unaided eye except by the results they show on the host 

 plant ; and a brief outline of the history of the development 

 of a fungus may better enable us to understand each other. 



A fungus is a minute plant growth, destitute of green col- 

 oring matter, which feeds by means of minute, thread-like, 

 transparent roots, that penetrate the material aflbrding it 

 food. These roots, known as mycelium, are much like 

 bleached cotton fibre in appearance. I can think of no 

 illustration that will give one a better idea of their structure 

 than this, very much reduced in size, of course, and aggre- 

 gated, or compacted into close masses. 



Fungi are divided into two groups, the saprophytic and 

 the parasitic fungi ; the first represented b}^ the mushroom, 

 and the second by the grape mildews, the grain rust or the. 

 potato blight. Taking the potato blight, which is more or 



