WINE-MAKING IN CALIFORNIA. 45 



THE UNIVERSITY VINEYARD PLOT. 



The University vineyard plot, in which the field observa- 

 tions were made, and the specimens for laboratory work were 

 taken, is situated upon the north side of the University 

 grounds, and upon the extreme east of that part of the tract 

 which was placed under the control of the Agricultural De- 

 partment, and set apart for experimental purposes. It has a 

 southeast exposure, which renders it somewhat more favora- 

 ble than the lower lands to the earlier " putting out" of the 

 vine and consequent longer season which is needed in this 

 locality. 



The soil is a heavy, refractory clay loam, not easily culti- 

 vated except upon the surface, and is underlaid by a stiffer 

 clay at a depth of a few inches, followed at a slightly lower 

 depth, by an intermixture of coarse gravel and rocks, thus 

 forming a soil ill adapted to vine growth, and a sub-soil not 

 easily penetrated by the roots. The plot, which is from the 

 nature of the soil difficult to drain, is relieved of this trouble, 

 to a great extent, by the steep inclination and loose-walled 

 bank on the lower side. 



The total number of old vines (and some young ones in- 

 termixed, which have been grafted on resistant stocks) 

 amount to only sixty-eight, including, beside the common 

 vinifera varieties, some that in other countries have shown 

 special fitness for certain forms of the phylloxera, 'and which 

 are not found among the infected vineyards of our State. 

 Some of these are hybrids of stock, elsewhere bearing the gall 

 type of insects in abundance. 



Thus we have been specially fortunate in having a collec- 

 tion of varieties which, presumably, make it possible to pro- 

 duce and study all types that have been observed elsewhere. 



The Winter State of the Insect. -The first important point 

 to be considered was to determine the habits and movements 

 of the insect at different seasons of the year, and especially to 



