122 BULLETIN 903, IT. S. DEPARTMENT OF AGRICULTURE. 



fore, that the planting of vines on land from which phylloxerated 

 vines have recently been pulled up is a dangerous procedure. It is 

 next to impossible to pull up grapevines without leaving pieces, of 

 roots in the ground. In the case of vine nurseries, this danger is very 

 apparent. 



OLD STUMPS. 



Since the phylloxeras may live under the bark of vine stumps to 

 several inches above the soil surface, it is apparent that these infested 

 stumps might possibly be a means of diffusion if sound vines should 

 be placed near them. Such stumps, however, soon decay after they 

 have been pulled from the ground and severed from their roots. In 

 the active season, however, any insects dwelling upon them would 

 hasten to leave and seek other food, so that in this season it is quite 

 possible for diffusion to occur from the stumps. In the winter the 

 phylloxeras would all be hibernants, and these would die as the stump 

 decayed. 



SUMMARY. 



HISTORY. 



The grape phylloxera was introduced into California about the 

 3 7 ear 1858, having been brought on vines imported by settlers from 

 the East. It thus appears that the pest arrived on the Pacific coast 

 at least as early as it reached France, where the first evidence of its 

 activity was vaguely noted in 1862. 



For many years previous to this introduction the Spanish settlers 

 and Missions had cultivated on a moderate scale the Mission grape, 

 and this, though a very susceptible variety, as was afterwards 

 proved, had flourished without disease. About the time of the advent 

 of the phylloxera grape culture was receiving a great impetus, and 

 many European varieties were being introduced which shortly showed 

 signs of disease in localities in which the eastern vines had been 

 planted. 



The phylloxera has since spread throughout most of the grape 

 districts of California wherever conditions have been suited to it, 

 but never has the pest assumed such disastrous proportions as it did 

 during the first years of its ravages in France. It is possible that 

 the insect has never reached such isolated vine districts as those of the 

 southern California counties, but in many of such isolated localities 

 the conditions are unsuited to the insect, and thus we can not be 

 certain that it did not reach these places and fail to establish itself. 



Coming upon the scene at the infancy of the commercial grape 

 industry, the phylloxera has been present throughout the growth 



