CONTRIBUTIONS ON THE CORN ROOT-APHIS. Ill 



corn or an infested aster bed, they will not be troubled with this pest, 

 provided the wild food plants of the pest were removed from the 

 vicinity of the bed as mentioned above. 



OTHER CULTIVATED FOOD PLANTS. 



A root-aphis was reported, in October, 1908, by the M. Crawford 

 Company, of Cuyahoga Falls, Ohio, to be injuring strawberry plants 

 in a field which had been in corn the year before. This aphis was 

 identified by Mr. Theo. Pergande as Aphis maidi-radicis. 



Mr. C. H. Popenoe, of this Bureau, collected it from the roots of 

 cabbage at Doncaster, Md., July 24, 1907. These specimens were 

 also identified by Mr. Pergande as Aphis maidi-radicis. 



These aphides were found to be injurious to pumpkin and water- 

 melon at French Creek, W. Va., in July, 1908, as reported in a letter 

 from Mr. F. E. Brooks: 



I have found the aphis on roots of watermelon and pumpkin growing where 

 an old. sod of orchard grass was plowed down last spring. The cucurbits grew 

 about 100 yards from a cornfield that was infested last season. 



What is supposed to have been Aphis maidi-radicis was reported 

 from Dover, Del., to be injuring French artichoke. Mr. Theophile 

 Berneau, of Dover, in a letter to the Bureau of Entomology, August 

 25, 1908, says: 



I am cultivating French artichoke, Cynara scolymus, and have some trouble 

 with minute insects which settle on the roots and suck the sap, to the great 

 detriment of the plant. 



Mr. Berneau reported that these insects were accompanied b}^ a 

 great number of ants. 



This species was reported as injurious to dahlia at Longmeadow, 

 Mass., and at Springfield, Mass., in 190G. In a. letter from Spring- 

 field dated June 4. 1906, Mrs. T. G. Forster says : 



I have set out a few dahlia bulbs and find they will not grow. To-day on 

 unearthing some of them I find the roots and also the sprouts — the part in- 

 side the ground — covered with small white lice which seem to eat the small 

 new roots as they start to grow. Have had some trouble with them before. 



DESCRIPTION AND SYNONYMY. 



There is some question as to whether, in our study of this insect, 

 we are dealing with one or with more than one species. There is a 

 form which feeds on the fleabanes (Erigeron) and on wild asters, 

 described by Cyrus Thomas in 1879 as Aphis middletoni. This is 

 probably a distinct species, although further study may show that it 

 is the same as Aphis maidi-radicis, in which case both forms would 

 be known as Aphis middletoni Thos. 



Specimens found on the roots of corn, in Oklahoma, by Mr. T. D. 

 Urbahns, of this Bureau, and on cotton, in South Carolina, by Mr. G. 



