58 



dollars-and-cents point of view. The Department expends for work of 

 this kind about |20,000 annually. It is known from careful and re- 

 liable data collected in 1890 that about 5,000 grape growers in this 

 country treated their vines in accordance with the directions issued by 

 the Department. Of these only 10 per cent, met with indifferent suc- 

 cess. The remainder, or about 4,500, estimated the increase in their 

 crop as a result of the treatments all the way from 15 to 80 per cent. 

 From a money point of view this meant for some as high as |2,000, 

 while for others the amount was as low as $10 ; the average, however, 

 is about |50. But let us put it at the very lowest figure, say half this 

 amount, or $25 profit for each v^c the 4,500 who used the remedies suc- 

 cessfully ; this will give us a total profit of $112,500, or nearly six times 

 the amount expended by the Department in the entire ^ork. It must 

 be remembered that this is for only one disease. Fully as good a show- 

 ing could be made with others, such as potato rot, apple and pear scab, 

 pear, plum, and cherry leaf-blight, etc. 



A few words now in regard to the modern method of warfare 

 against the insect enemies of plants. People as a rule are sufficiently 

 familiar with the manner in which insects cause the loss of crops to 

 know that in fighting them two methods may be adopted, namely pre- 

 vention and cure. By prevention is meant such means as stamping out 

 these pests before they have an opportunity of spreading ; taking ad- 

 vantage of their habits, and planting such crops as they are likely to 

 destroy at times when they can do the least damage, and other similar 

 means. The importance of work of this kind cannot be over-estimated, 

 as is shown by a case in New England which is now attracting wide- 

 spread attention. A few years ago there was introduced into Massa- 

 chusetts an insect from Europe which was thought to have value as a 

 silk producer. This insect, known as the gypsy moth, already had a 

 bad reputation ; but despite this, it was brought over here and, not- 

 withstanding precautions were taken to keep it within bounds, it got 

 away and soon began to multiply rapidly, carrying destruction to vege- 

 tation of nearly all kinds wherever it went. It is probable that by 

 prompt and energetic action the foe could easily have been wiped out 

 in its incipiency, but it seems that matters were allowed to take their 

 own course, so that now the pest covers a territory of at ^east fifty miles 

 square. At last the people of Massachusetts have their eyes open to 

 the serious nature of the matter, and have gone to work in earnest to 

 wipe out the pest. Last year $50,000 was expended in the work alone 

 and even more will be expended this season. 



The curative method of dealing with these foes resolves itself into 

 two distinct lines ; first, that of killing the pests outright, such as by 

 hand picking, mechanical devices, applications of poisonous liquids, 

 powders, etc. ; and, second, the introduction and encouragement of their 

 material enemies mainly in the shape of insects themselves. Thanks 

 to the efforts of the National as well as State Governments, the first 

 method, and especially the application of poisons such as Paris green, 

 London purple, etc., is in a general way now pretty well understood. 

 In fact, it does not seem like an exaggeration to say that the money 

 saved each year to the husbandmen of this country by work of this kind 

 is more than enough to pay the total expense of the Department of 



