37 



FOR PERNICIOUS SCALE. 



Aspidiotus Pevniciosus. 



For badly infested orchards I recommend: One and one quarter gal- 

 lons of whale oil; twenty-five pounds of sal soda; dissolve the sal soda in 

 twenty-five gallons of water and heat it to boiling. When boiling pour 

 the whale oil in. Apply the wash when cooled to 130 degrees F. The 

 whale oil forms a kind of emulsion, most of the oil remaining free. After 

 allowing this dose to act for three or four weeks, apply caustic solutions in 

 this proportion: One pound of concentrated lye (American), of 80 per 

 cent; or four fi^fths of a pound of powdered caustic soda, of 98 per cent; or 

 one pound of solid caustic soda, of 76 per cent; or one and one half pounds 

 of solid caustic soda, of 63 per cent. Any one of these to one half pound 

 of commercial potash, at 52 per cent. To be dissolved in six gallons of 

 water. 



Mode of Preparing Washes. 



The easiest way to prepare the alkali washes, especially the solid concen- 

 trated lye, is by suspending the material in a barrel of water, either putting 

 it on a perforated piece of tin or colander. Being thus suspended the dif- 

 fusion is quite rapid, and the material will require but little looking after. 

 By using hot or boiling water the action, of course, is hastened very much. 

 When dissolved thoroughly, each kind having been kept separately, they 

 are mixed and stirred well, so that they become thoroughly mixed. The 

 liquid should be strained through a fine sieve (brass) or a cloth, so that no 

 clogging is possible when the wash passes through the nozzle. 



The San Jose nozzle has been and is very generally used, but for lye washes 

 it is, in my opinion, inferior to the Imperial and the Cyclone. The latter 

 has the advantage of throwing the stream better on the underside of branches 

 and foliage. When a pump with two outlets is at work, the two kinds of 

 nozzles may be used to advantage. One man may work principally on the 

 upper part of the tree with the Imperial (because its spray, being thrown 

 straight, hits the more vertical branches squarely), while the other man 

 will reach the lower more horizontal branches with the Cyclone spray, car- 

 rying, as it does, either upward or downward. 



A very good nozzle is that invented by John Crofton, and sold by H. P. 

 Gregory and Woodin & Little. It has the advantage of clearing itself by 

 a turn of the bib. Its spray is similar to that of the Cyclone nozzle. 



Caustics. 



The object to be obtained by using the caustics after the sal soda and 

 whale oil is to saponify any oil that might have remained on the tree, and 

 which would have a tendency to clog the poi'es of the bark. I believe this 

 treatment will prove the most eflicacious yet recommended. 



The cost of whale oil is 30 cents a gallon, in fifty-gallon barrels; 35 cents 

 in cases. As to caustic, it must be remembered that the price will vary 

 according to quantity, and that the purest product is the cheapest. The 

 green bank, 98 per cent, is considered the best and the least varying; next 

 to this, American concentrated lyes; George F. Lewes, Menzies & Co. seem 

 to be most reliable. 



In the moist coast counties we would recommend the caustic in this pro- 

 portion for pears, apples, and plums, the trees to be perfectly dormant: One 

 pound of solid concentrated lye (American), of 80 per cent; four fifths of 

 a pound of powdered caustic soda of 98 per cent, one pound of solid caustic 



