CHAPTER XVII 

 INSECTS INJURIOUS TO BEETS AND SPINACH * 



The Beet-aphis f 



THIS species was first described by Mr. W. R. Doane in 1900 

 and seems thus far to have been found only in Washington and 

 Oregon. " Attention was first called to this pest/' he says,f " in 

 1896, when it was found that a field of two or three acres of beets 

 was generally infested, a strip of twenty-five to a hundred yards 

 being so badly injured that the beets were nearly all soft and 

 spongy, and the plants much smaller than the average. 



" It has been even more destructive in Oregon than in Wash- 

 ington, at least a thousand tons of beets having been destroyed by 

 it in one year in a single valley devoted largely to beet-culture. 

 Like very many other beet-insects, this species infests also several 

 wild or useless plants. 



" The smaller rootlets of the beet are first attacked by this 

 aphis, and if it occurs in considerable numbers these are soon all 

 destroyed, and the leaves thereupon soon wither, and the whole, 

 beet shrivels and becomes spongy. This wilting of the leaves will 

 frequently, in fact, be the first thing to attract the attention of the 

 beet-grower. The actual injury to the crop will, of course, depend 

 largely upon the time when the attack of the aphis is made. If the 

 plants are small they may be readily destroyed, while if they are 

 practically full grown the loss of the small rootlets will not 

 materially affect them. 



* See Forbes and Hart, Bulletin 60, 111. Agr. Exp. Sta., and F. H. Chitten- 

 den, Bulletin 43, n. s., Div. Ent., U. S. Dept. Agr. 

 t Pemphigus betas Doane. Family Aphidae. 

 J Bulletin No. 42, Wash. Agr. Exp. Sta. 



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