agricultural experiment station. 143 



Remedies. 



The experience of Bailey, Henderson and Munson would lead 

 one to conclude that there is no remedy at present known that is 

 entirely effective. 



Henderson writes us that one of the best remedies is Fir Tree 

 Oil, and another very good one is Cole's Insect Destroyer but the 

 cost of the latter almost prohibits its being used in large quanti- 

 ties. Prof. Bailey has had considerable experience with Fir Tree 

 Oil but does not find it entirely satisfactory, though of considera- 

 ble value. 



Prof. Munson says he has used an alcoholic tincture of Pyreth- 

 rum and finds it quite satisfactory. There is a general belief that 

 the red spider is readily destroyed by a copious use of water and 

 will not flourish in a moist atmosphere. The impression of those 

 who have had most experience with this mite, is that it may be 

 very bad in a moist atmosphere. Prof. Munson relates one 

 instance of a cucumber house where the plants were badly infested 

 though the atmosphere was kept quite moist. We believe, however, 

 that spraying the plants frequently with water, would help hold 

 them in check by reducing the temperature. They seem to enjoy a 

 high temperature. 



Henderson believes an ounce of preventive is better than a 

 pound of cure and if the plants are kept in good health they will 

 resist the disease. He has frequently noticed that where plants 

 become pot-bound it would make its appearance while others 

 potted at the same time and shifted as the occasion required would 

 be perfectly free from it, thus showing that the disease is alto- 

 gether the result of imperfect conditions of growth. We have 

 commented upon this elsewhere under the head of host plants. 



Fir Tree Oil can be obtained from August Rolker & Sons, 136 

 W. 24th St., N. Y., at a cost of $3.25 per gallon, in five gallon 

 lots, less ten per cent, for cash with order. It should be diluted 

 about one hundred times with water and applied with a syringe or 

 atomizer. 



