22 SCALE INSECTS, 



neither the parasitic nor predacious insect enemies will 

 remove the responsibility of keeping this pest in check 

 from the horticulturist. 



Artificial Remedies. Climatic conditions are an im- 

 portant factor under this head. Successful methods of 

 treatment in California have failed in states farther east. 

 As before stated, a knowledge of life-history shows that 

 treatment in this section of country will vary with season 

 of year. If applied when young are emerging, those ex- 

 posed will be destroyed, while later broods will safely come 

 forth. 



Washes or Sprays. Applications, then, which are 

 etfective during winter months when all scales are in same 

 stage, and when death to the individual means death to its 

 jjrogeny, are certainly the most to be desired. Such washes 

 then shall be discussed. Many washes have been used. 

 The effects of all have been noted upon the plant as well 

 as upon the jjest. It will suffice here to give the one which 

 has proven the most satisfactory, and which happily is not 

 the most expensive, nor the most difficult to apply. The 

 most effective is the whale - oil - soap wash. Mr. Robert 

 Emery, of Chestertown, Md., first called attention to its 

 special merits against this scale, though previously rec- 

 ommended as a general wash against scales by Comstock. 



Composition of the Soap "SVash. Two pounds whale- 

 oil soap; one gallon water. Apply warm, thoroughly 

 drenching the tree. (The best grade of whale-oil soap 

 costs 4 cents per pound.) 



Time OF Application. Twice a year. (1) In fall, after 

 foliage has fallen. (2) Just before blooming, in spring. 



Causes for Varying Results. The destruction of in- 

 sects may not be noticeable for several weeks after appli- 

 cation. Time is required to allow solution to soak through 

 waxy covering of scale. Should rainy weather follow the 

 time of treatment, the results will not be so great. This, 

 coupled with the fact that one application may not wet all 

 parts of the tree, makes it necessary to give the tree two 

 thorough drenchings, at times stated above. The strength 



