﻿OF THE STATE ENTOMOLOGIST. 85 



PRACTIC-VL, CONSIDERATIONS. 



The practical man may consider the illustration of these difier- 

 ences as unimportant and trivial, however much they may interest 

 the entomologist. Yet it is of much practical importance to know 

 how to distinguish between these two insects. From present knowl- 

 edge of the subject, it is highly probable that, just as the moths of 

 the one species appear mostly in early Spring, and of the other mostly 

 late in the Fall, so each is, in a general sense, confined to particular 

 plants — the Spring species preferring our fruit trees, and the Fall 

 species preferring the Elm, Thus the time to put forth our efforts to 

 catch and destroy the wingless moths will vary according to the 

 nature of the tree to be protected and the insect to be dealt with. 



In the case of the Spring species, the scraping of loose bark from 

 the tree and otherwise cleansing it of dead leaves, cocoons, larva- 

 cases, etc., a short time before the hatching of the worms, or before 

 the buds of the tree commence to open, will prove an effectual pre- 

 ventive measure; as thereby many of the eggs will be destroyed. 

 Moreover, a tree kept clean of loose bark will be less subject to its 

 attacks. The same argument will not apply to the Fall species, which 

 attaches its eggs in any exposed position. It would seem, also, that 

 the mode of trapping the moths will have to be somewhat modified, 

 according to the species to be dealt with ; lor while Dr. LeBaron 

 found the tin and rope trap described last year so eflectual with the 

 Spring Canker-worm, it does not appear to afford any barrier to the 

 Fall species, judging from the following notes, kindly furnished by 

 Mr. Mann : 



Nov. 8, 1873. Warm last night, with rain, which still continues. Found 25 $ and 

 one (^ pometaria. Found 4 of the $ above the LeBaron zinc band. 



Nov. 9. Found 2 cj', 37 $ pometaria ; 2 2 above the zinc band. 



Nov. 12. Snow last night, followed by cold sleet. Found 9 $ pometaria, 1 above 

 the zinc. 



Nov. 15. Only 6 § pometaria ; none above the band. Last three days freezing- 

 cold, but not stormy. 



Nov. 18. Several days of rain and snow. 1 $ pometaria. 



Nov. 22. 6 2 , 2 cf pom.etaria. 



Dec. 4. Yesterday tbavving, to-day also. The weather since Nov. 22 has been 

 cold, with occasional snow, and the ground has been frozen, and I have failed to find 

 any Anisopieryx pometaria:, but to-day I cauifht 11 rf, 102 §, 2 $ above the zinc band. 

 I have no doubt that tliesmallness of the number ot $ found above the bands of zinc is 

 due to my promptness and diligence in detecting and destroying them before they liave 

 had tin)e to mount the tree ; because, according to the theory on whieli the experiment 

 was tried, the $ ought to be found on the outside of the strips, if their ascent has been 

 prevented by them ; wliile in fact, (excluding those lound on the house or fence, etc.,) 

 the majority of the 5 have been caught befure they reached the bands; further, be- 

 cause I tried the experiment with 3 or 4 5. and found that as soon as they reached the 

 top of the band, they climbed over it, anO began to ascend the tree. Being sati.^lied by 

 this positive evidence, which would outweigh any amount of negative evidence Irom 

 those who have not seen it, 1 put printers' ink on the outside of the zinc strips. (I 



