THE INSECT PESTS OF CLOVER AND 
ALFALFA 
By J. W. FOLSOM, Assistant Professor of Entomology:, 
University of Illinois 
Introduction 
This account contains a large amount of new information on the 
most injurious of the clover insects, and on some of the less important 
species as well. Unless otherwise indicated, the observations were 
made by the writer during three summers in which he was employed 
by the State Entomologist, Dr. Stephen A. Forbes, for the special pur- 
pose of studying these important insects. 
The volume of the results obtained — many of them as yet unpub- 
lished — is due in no small measure to the help of an assistant, especially 
in the routine work of the insectary ; and in this capacity there have 
served at one time or another, Messrs. E. V. Bronson, E. O. G. Kelly, 
R. L. Webster, and J. J. Davis. Their names appear later wherever 
their personal observations have been used. 
The present account contains not only new material, but also every- 
thing of importance that has previously appeared in our literature of 
the subject. The literature is large, but the greater part of it is a mass 
of more or less useful repetition, which traces back to a few sources. 
All the original articles are cited in the lists of references, as are also 
the more useful of "the compiled articles. These references, tho not 
voluminous, are comprehensive, and sufficient to guide one directly to 
all the authentic sources of information on each subject treated. 
Most of the illustrations were drawn for the State Entomologist 
by Miss Charlotte M. Pinkerton, Mr. F. Knab, and Mr. W. C. 
Matthews. Several electrotypes were obtained from the Bureau of 
Entomology thru the courtesy of the Chief, Dr. L. O. Howard. 
In the account that follows, consideration is given primarily to the 
insect pests of red clover, and secondarily to those of mammoth clover, 
white clover, alsike, and alfalfa. The last-named plant, introduced 
into Illinois some ten years ago, is cultivated here and there in almost 
every county, and has been adopted as a food plant by a large number 
of the red-clover insects; but none of them have as yet injured it con- 
spicuously, so far as the writer has been able to learn. 
Injury to Clover by Insects 
A field of red clover in full bloom is alive with insects. Such a 
profusion of insect visitants, both as regards number of individuals and 
number of species at one and the same time, is afforded by no other 
plant that we know of, with the possible exception of alfalfa. In the 
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