CHAPTER XXII 



INSECTS INJURIOUS TO THE STRAWBERRY * 

 The Strawberry Root-louse t 



IF bare spots are found in the strawberry bed and the neighbor- 

 ing plants are unhealthy, the presence of the root-louse may be 

 suspected, especially if ants are abundant around the plants. 

 If present, the small dark green or blackish aphides will be found 

 clustered on the roots and stems, caus- 

 ing the plants to wither and die. The 

 individual aphid is only about one- 

 twentieth inch long, and deep bluish 

 or greenish-black when mature, the 

 younger stages being lighter, and 

 somewhat pear-shaped as shown in 

 Fig. 315. 



Injury by this pest was first noted 

 in southern Illinois in 1884 and a few 

 years later it became troublesome in 

 Ohio. In the late '90s it ruined 

 many beds on the Maryland-Delaware 

 peninsula and became established in 

 New Jersey. Since then it has become distributed on plants 

 throughout most of the States east of the Rockies, injury having 

 been noted in New Hampshire, Michigan, Minnesota, Kansas, 

 Texas, and Kentucky. Injury is most severe on light sandy 



* See L. Bruner, Report Nebraska Horticultural Society, pp. 49-100; 

 J. B. Smith, Bulletin 225, N. J. Agr. Exp. Sta.; A. L. Quaintance, Bulletin 

 42, Fla. Agr. Exp. Sta.; S. A. Forbes, 13th Report State Ent. of 111., pp. 

 60-180. 



t Aphis forbesi Weed. Family Aphididce. See Sanderson, Bulletin 49, 

 12th, 13th and 14th Reports, Del. Agr. Exp. Sta. 



441 



FIG. 315. The strawberry 

 root - louse (Aphis forbesi 

 Weed): wingless viviparous 

 female of late summer 

 greatly enlarged. 



