45 



clients in every conceivable proportion that the wit of man could de- 

 vise — have all been strongly recommended in print on what seemed to 

 be the very best authority. Yet, with the exception of two or three 

 of these articles — and these only if they be applied at a particular 

 period of the year — I believe them all to be equally useless and in- 

 efficacious. Indeed, after filling one volume with certificates from 

 the most respectable sources highly recommending, one after another, 

 every one of the above panaceas, it would be easy to fill another volume 

 with the doleful lamentations of men, who have tried them and found 

 them worthless. I know several orchardists troubled by this vile 

 pest, who have arrived at the conclusion, after experimenting in vain 

 with a dozen different remedies, that it is no use trying to fight it, 

 and that their apple-trees are irretrievably ruined and "gone up." 



As with all other Noxious Insects, before we can fight this Bark- 

 louse understandingly, it is necessary to know who and what she is, 

 how she is propagated from year to year, how she spreads from one 

 tree to another, and what are her peculiar habits and mode of life. [ 

 put her in the feminine gender, because, without a single exception, 

 all the scales that come under the notice of the fruit-grower contain 

 eggs under them, and are consequently all of them females. And 

 here, at the very outset, the inexperienced observer is often involved in 

 error and confusiop. There are two perfectly distinct Bark-lice, with 

 different habits and modes of life, commonly found in Illinois on the 

 apple-tree, which are popularly confounded together — by a very in- 

 definite application of the Definite Article — under the appellation of 

 "THE Bark-louse." The first — which is the one with which we are 

 now more immediately concerned — is a species introtluced into the 

 Eastern States more than seventy years a^o from Europe, but which 

 only penetrated into Illinois about fifteen years ago ; occupying at first 

 the districts bordering upon Lake Michigan, where it committed ter- 

 rible ravages, and thence spreading gradually Westward and South- 

 ward, till only a few years ago it touched the Mississippi River. The 

 second — which we will call "Harris's Bark-louse," and which will be 

 referred to more fully in the following Chapter — is a native- American 

 species, and has existed for time immemorial both in the East and in 

 the West, its original home being our native crab-trees, upon which I 

 observed it many years ago. The first cannot thrive except in com- 

 parativel}^ northern latitudes; for even in Champaign. Co., in Central 

 Illinois, as I am informed by Mr. M. L. Dunlap ("Rural"), although 

 it has been long known there, yet it does not increase so as to be at all 

 formidable; and, as I was told in Southern Illinois, it actually dies, 

 when it is introduced there upon young apple-trees brought from the 



