172 INSECTS rXFESTIXG THE CRAPE. 



tion of this pest, nor an account of the damage done to vine- 

 growers by its ravages, as the reports of the State Board of 

 Viticultural Commissioners, the report of Charles A. Wet- 

 more, Cliief Executive Viticultural Officer ; papers by Prof 

 E. W. Hilgard and others, of this State, and Prof. C. V. 

 Riley's Missouri Reports, have given full information of its 

 natural history, habits, etc. 



Unfortunately the presence of the grape-root louse (Fig. 

 151) in some of the Wneyards of this State is established 

 beyond a doul)t, and that a large acreage of vineyard property 

 has been destroyed by the ravages of this pest many of the 

 vine-growers can offer substantial vfiilications. 



Various opinions have l)een expressed as to how this insect 

 spreads from one vine-growing district to another. A asserts 

 that the winged individuals tly from one vineyard to another, 

 as other species of Aphididse spread on their resj^eetive food 

 plants. B considers that the insect is spread l)y transporting 

 from infested vineyards rooted vines and cuttings on which 

 the Winter egg is deposited. C claims that the grape-root 

 louse was brought on his premises by boxes returned from 

 market in which grai)es had been sliij)i)ed. 1) insists that he 

 has not liad any boxes returned to his premises, that the cut- 

 tings he used were grown in his own vineyard, yet on a patch 

 of ground five rods square the vines are infested by the Phyl- 

 loxera^ although the latter are not found on his older vines 

 from which the cuttings were taken. The opinions of A, B, 

 C, and D, may individually or collectively be correct, and as 

 the pest has secured a foothold on their i)remises, the query 

 arises : ''What can be done to save the infested vines?" 



Since the first of .January, 1880, I have visited several locali- 

 ties in which I found grape-vines infested by the grape-root 

 louse, and in nearly every case the appearance of the vine 

 imlicated the presence of the pest. In conversation with the 

 \ iucyard owners, in relation to the decay of their vines, the 

 following questions and answers may be takeii as the result of 

 such investigations : 



Question — How many crops of grapes have you taken off of 

 these vines? Answer (from different growers) — From ten to 

 fifteen crops have bcnni taken from this vineyard. 



