122 BULLETIN 903, U. 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 phylloxera? 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 
phylloxera? would all be hibernants, and these would die as the stump 
decayed. 
SUMMARY. 
HISTORY. 
The grape phylloxera was introduced into California about the 
year 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 
