No. 6. DHPARTMBNT OF AGRICULTURE. 149 



ment. It is remarkable to what extent orcharding is developing 

 in the State of Pennsylvania at the present time, and the keen in- 

 terest in this subject naturally causes many persons to write to this 

 office for help along the line. As a rule, the communications per- 

 taining to other subjects than those which we regard as belonging 

 properly to that of Economic Zoology are referred to respective 

 specialists for reply. We give the public to understand that our 

 specialty includes pest suppression and related subjects, as well as 

 general entomology, zoology, etc. 



2. INVESTIGATIONS AND EXPERIMENTS 



The work of the office in correspondence, publication, inspection 

 (of nurseries and private premises), and demonstrations has been so 

 heavy during the past year that to a great extent the investigations 

 and experiments were reduced in numbers. However, those that 

 were conducted brought out some points of great value. Among 

 these are the following: 



(a) Spraying loitli Lime-sulfur Solution. It has been proven be- 

 yond controversy that the lime-sulfur solution is the best, safest and 

 cheapest material to use in spraying all trees, shrubs and vines 

 while dormant, and proper horticultural practice calls for the thor- 

 ough spraying of all stone fruits, whether infested with scale insects 

 or not. We have been surprised with the cheaimess and ease with 

 which the concentrated lime-sulfur solution can be made. In an 

 ordinary galvanized iron boiling tub over a crude furnace we boiled 

 lime-sulfur solution fast enough to keep one tractor sprayer going 

 all the time, and did not demand the services of an extra man to 

 do the boiling. By simply putting the powdered sulfur into the 

 water, and putting in the fresh quick lime, and stirring it a little 

 to keep it from settling to the bottom before boiling commenced, we 

 were able to thus start the boiling, which continued while the pre- 

 viously boiled and diluted material was being sprayed out of the 

 tank. On return from the orchard the spray tank was filled with 

 the boiled product, diluted and properly tested with a hydrometer, 

 and while one man was making the solution to the proper strength, 

 the other was preparing the next batch for boiling. A brisk fire with 

 an abundance of fuel was than kindled, and the boiling left to itself 

 until the return for another spray tank full — thus requiring but two 

 men to do the spraying and boiling at the same time. 



Variation of the Lime-sulfur Formula: We have further proven 

 our earlier statement that the lime-sulfur solution can vary a great 

 deal and at the same time always bring good results, if used strong 

 enough and thoroughly applied. The easiest prepared formula which 

 we have used calls for two jjounds of quick lime and one pound of 

 sulfur, boiling for one hour in each gallon of water, using these pro- 

 portions for a larger quantity. A modification of this formula shows 

 that good material can be made by boiling sixty pounds of fresh 

 lime with one hundred and twenty-five pounds of sulfur in fifty 

 gallons of water for one hour. Several other modifications of the 

 concentrated formula are given and will do well. Thus we have en- 

 tirely forsaken the old home-boiled "seventeen-twenty-two-fifty" for- 

 mula. This is for the purpose of getting rid of the sediment and mak- 

 ing a storable solution. After the material is boiled by the concen- 



