13 



As the Buhach at first merely paralyzes the insect, it is necessary 

 that this influence upon the latter should continue until death results. 

 To accomplish this some viscid substance should be combined with the 

 solution of Buhach and water, in ordei to cause the solution to adhere to 

 the insects for a sufficient length of time to deprive the latter of their 

 lives. One of tbe best known substances of this kind is glucose, a semi- 

 liquid refuse of sugar refineries. This substance combines readily with 

 the Buhach solution, and does not appear to have an injurious effect upon 

 the plants that have been sprayed with it. A low grade of brown sugar 

 would doubtless answer the same purpose, although not in an equal 

 degree, not being so viscid when mixed with water. 



Besides using the Buhach in a dry form, and mixing it with water, it 

 is sometimes also mixed with alcohol, in the proportion of 1 pound of 

 Buhach to a quart of alcohol ; this should stand in a closed vessel for an 

 hour or so, when it may be diluted with water to any extent required. 

 In regard to this solution Prof. E. W. Hilgard, of the University of Cali- 

 fornia, writes as follows to the Pacific Rural Press of May 5, 1883 (p. 

 413): 



" I find that the effect of the Bnhach is materially increased in dura- 

 tion when instead of the tea the diluted tincture is used, as was sug- 

 gested by Professor Riley two years ago. The reason is that the alco- 

 hol extracts with the essential oil also a green resin, which prevents 

 the too rapid evaporation of the volatile oil, and makes it stick to the 

 insect. 



" A quart of alcohol to a pound of powder is the best proportion, but 

 less alcohol may be used. The alcohol may simply be left on the powder 

 for an hour, and the whole then put into 45 or 50 gallons of water, if to 

 be used through a ' San Jose nozzle.' But it is far better to let the 

 alcohol percolate through the powder, and thus get a clear tincture, of 

 which aliquot parts may at any time be used through any nozzle what- 

 soever, after proper dilution with water. Thus it becomes a great con- 

 venience, since the insecticide solution is ready at any moment without 

 need of boiling or dissolving, and thus the work may be done just when 

 wanted without any preparation. I find a solution made as above 

 quite strong enough for any ordinary insect, including the hairy cater- 

 pillar, which at first seems not to mind it much, but after a while tum- 

 bles down and succumbs after vain efforts to crawl away. I have not 

 had an opportunity of trying it upon the Diabrotica or 'spotted lady- 

 bug,' but am told that it also succumbs despite its ability to eat almost 

 anything from tobacco to belladonna and henbane. All the aphids 

 yield to it at once, as does the Red Spider when, hatched ; but it will 

 not kill eggs." 



In using the Buhach out of doors tin; best effect will be obtained 

 when the weather is still and rather cool. In very hot weather the in- 

 secticidal properties of the Buhach evaporate too rapidly, thus render 

 ing its time of action so brief as to permit the insect in many cases to 



