47 



especially on the latter. In the southern part of the State it iujured 

 the tomato crop to a considerable extent. Spraying with Paris green 

 and with other arsenical compounds was tried with considerable success 

 previous to the ripening of the fruit, but there is considerable danger 

 in its use and it is best to thoroughly drench the plants that have been 

 treated with clear water a day or two after the use of the insecticide. 

 Experiment on a limited scale shows that it can be kept from corn by 

 the same remedies, but how far this would be practicable in the field 

 has not jet been demonstrated. 



The Striped Flea-beetles (Phyllotreta vittata and P. sinuata) did not ap- 

 pear at all on early Crucifers, nor have they been observed in any con- 

 siderable numbers in this vicinity at any time during the growing sea- 

 son. Whether this notable riddance was due to atmospheric conditions 

 or to the scarcity of the fostering weeds, Lepidium and Arabis, I am not 

 able to decide. 



The Corn Flea-beetle (Chcetocnema pidicaria) was reported to me from 

 various localities as unusually numerous aud injurious. Mr. Falcon, of 

 St. Clair County, feared that he should lose his first planting from its 

 attacks, but from later accounts the plants recovered more rapidly 

 than he had expected. 



The Plum Curculio was much reduced in numbers during winter, and 

 as there was in this section, and indeed throughout the State, an almost 

 entire failure of stone fruit crops, with the exception of the sour cher- 

 ries, which the insect rarely attacks, tbere was very little of the work 

 of the latter observed. A small proportion of the few early peaches 

 that set were punctured, but that the midsummer drought prevented 

 the development of the larvse was indicated by the fact that such late 

 peaches as there were did not show a single one of the food punctures 

 which commonly so disfigure them. On one tree which the previous 

 year had suffered so much in this way that the fruit was absolutely 

 worthless, was a single peach that reached perfection without one 

 stroke from the beak of a curculio ; and similar observations were 

 made on other trees on which a very little fruit ripened. Nor was I 

 able to find Conotrachelus breeding in apples, although during June 

 aud July I examined nearly six hundred specimens of fruit, a few of 

 which showed punctures that might have been made for food. Should 

 other conditions be favorable, I think, so far as this insect is concerned, 

 we may predict for 1891 fine crops of stone fruits. 



Plant lice, always quite abundant in the spring, amounted this year 

 almost to a scourge. Trees, shrubs, and herbs alike suffered, and for 

 many plants there was no after-recovery. The species causing the most 

 appreciable loss was probably the Grain Aphis (Siphonophora avenw). It 

 occurred throughout the State on all small grain, even on rye, causing, 

 undoubtedly, some shrinkage of that crop as well as of wheat, but its 

 most disastrous attacks were on oats. About the middle of May farm- 

 ers began to be alarmed for the safety of this crop, and subsequent 



