PRACTICAL ENTOMOLOGY. 



NOTES FROM THE ENTOMOLOGICAL LABORATORY OF THE MICHI- 

 GAN AGRICULTURAL COLLEGE. 



BY PROF. A. J. COOK. 



THE '• BLACK ARMY-WORM." 



Agrotis /e?iuica, Tauscher.— Family Nociuidcu. Order Lepidoptera. 



Daring tlie past few years, many new insect pests have crowded upon ns. 

 Hardly a season passes by, daring which some part of oar country is not 

 devastated. One year the meadows and clover fields of New York are 

 stripped of their herbage ; then the strawberry fields of Illinois are pilfered 

 of their delicious fruit. Thus every season comes freighted with new evil. 

 The present summer is peculiar in ushering in two serious pests, neither of 

 •which has ever before attracted the least attention anywhere in the country. 

 What is most remarkable, both of these new raiders made their advent in 

 Michigan. One of these new pests has been known as a rare moth, and has 

 been taken in California, the Northern and Eastern States, and in Canada. 

 This year it swarms down upon Michigan in such multitudes as to earn and 

 receive the sobriquet of Army-worm. The other insect is a beetle of the 

 weevil family. This I have known to be common in Michigan for 15 years ; yet 

 no one has complained of it as an enemy; indeed, its habits as a larva were 

 all unknown. This year it girdles the crown of the strawberry so as to do no 

 inconsiderable mischief. Why insects usually rare siiould all at once come 

 in multitudes, and why well known insects should suddenly change their 

 habits, are questions which as yet we may hardly answer with certainty. The 

 greater abundance may result from favorable seasons, in respect to climate 

 and absence of insect and bird enemies; while changed habits may result 

 from a scarcity of native food plants, consequent upon the cultivation of the 

 soil by man. 



The Black Army-worm, to use a name given by the gardners where this 

 new enemy has wrought its mischief, has been very common and destructive 

 at Bay City, Portsmoutii, Saginaw City, on the shore of Lake Huron as far 

 north as Harrisville, and also on the Lake Michigan shore at Traverse City. 

 More lately I have received this same insect from Mr. L. S. Abbott, of the 

 Lewiston, (Maine), Journal. Mr. Abbott states that the insect is new to Maine, 



