BUGS, AND OTHER INSECTS: 



HOW TO KNOW THEM -HOW TO DESTROY THEM. 



BABK-LICE OF THE APPLETBEE. 



— There are two species of bark-lice that 

 attack the apple-tree in the United States. 

 The first, which is a native North 

 American insect, is now known as Harris' 

 Bark-louse. The color 

 'of the scale is dirty 

 white, and its form is 

 irregular, being usually- 

 egg-shaped; but, how- 

 ever variable in outline, 

 is always quite flat and 

 causes the infested tree 

 to wear the appearance 

 of Figure i ; while the 

 minute eggs which are 

 found under it in winter 

 time are invariably 

 blood-red or lake-red. 

 This species has scarce- 

 ly ever been known to 

 increase sufficiently to 

 Fig i. do material damage, for 



'the reason doubtless that there have, hith- 

 erto, always been natural enemies and 

 parasites enough to keep it in due 

 bounds. 



The second species, which is known as 



.the Oyster-shell Bark-louse, is by no 



means so harmless however, for it is one 



vof the most pernicious and destructive 



.insects which the apple-grower in the 



Northern States has to contend with. 



"This species may always be distinguished 



from the former by having a very uniform 



muscle-shaped scale, of an ash-gray color 



(the identical color of the bark), and by 



these scales containing, in the winter 



time, not red, but pure white colored 



eggs. 



There is scarcely an apple- orchard in 

 ■Northern Illinois, in Iowa, or in Wiscon- 

 sin, that has not suffered more or less from 

 its attacks, and many an one has been 

 slowly but surely bled to death by this tiny 

 sap-sucker. Its extension southward is un- 



doubtedly limited, for though so abund- 

 ant in the northern half of Illinois, ob- 

 servation has clearly proved that it can- 

 not exist in the southern half of the same 

 State. 



The oyster-shell bark-louse produces 

 but one brood annually, and these eggs, 

 therefore, remain under the scales for 

 more than nine months of the year, sub- 

 jected alike to the continuous warmth ot 

 the fall months, and to the severe frosts 

 of winter; freezing and thawing again 

 and again, without their vitality being in 

 in the least impaired. 



Remedies. — These may be summed 

 up in a very few words, and consist for the 

 most part in prevention, and we again urge 

 a strict examination of every young tree 

 before it is planted. If an orchard is 

 once attacked before its owner is aware 

 of it, much could be done on young trees 

 by scraping the scales off in winter, but 

 on large trees, where it is difficult to reach 

 all the terminal twigs, this method be- 

 comes altogether impracticable, and it 

 will avail but little to cleanse the trunk 

 alone, as most of the scales containing 

 living eggs will be found on the terminal 

 branches. Alkaline washes, and all other 

 washes, except those of an oily nature, 

 such as petroleum or kerosine, are of no 

 avail when applied to the scales, for the 

 simple reason that they do not penetrate 

 and reach the eggs, which are so well pro- 

 tected by these scales; and it is very 

 doubtful whether any solution can be used 

 that is sufficiently oily to penetrate the 

 scales and kill the eggs without injuring 

 the tree, especially while the sap of the 

 tree is inactive. Hence, the bark-louse 

 can only be successfully fought at the 

 time the eggs are hatching, and the young 

 lice are crawling over the limbs. The 

 time of year in which this occurs has al- 

 ready been indicated, and the trees should 



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