214 AGRICULTURE ON THE PACIFIC SLOPE 



are but little injured by phylloxera and on which the Euro- 

 pean vines can be grafted. Riparia Gloire de Montpellier 

 and Riparia Grande Glabre are am'ong the best of these, but 

 in dry places Rupestris should be planted. In selecting 

 resistant roots you should take great care to get a sort which 

 is^adapted to your particular soil and which will be the right 

 sort of stock for the particular European variety you wish 

 to grow. The cuttings of the European varieties should be 

 freed from phylloxera eggs, when brought into a region 

 which is free from phylloxera. This may be done by putting 

 the cuttings into a box or barrel, pasting paper over the 

 cracks, and placing a saucer full of carbon bisulphid on top 

 of them and closing with a tight-fitting cover. In an hour 

 and a half, or in some cases a less time, the cuttings may be 

 taken out. (Carbon bisulphid is poisonous and easily catches 

 fire if brought near a light.) 



In very sandy soils the phylloxera does little harm, but in 

 clayey soil the damage is* very great. By means of its beak 

 the insect sucks out the juices of the root. The roots become 

 covered with swellings, and on the larger roots large spots of 

 decay form. In a short time the rooTdies~Below the injured 

 place. In midsummer the insects occasionally become winged 

 and come out of the ground. They may fly for short distances, 

 or be blown longer distances by the wind. (California Experi- 

 ment Station, Bulletin 192; Idaho, 46.) 



White fly. This is a very serious pest to oranges and 

 lemons in the East, and has recently been found in California. 

 The eggs are laid on the trees, and the young, when first 

 hatched, look very much like young scale insects. After 

 wandering about for a few hours they fasten themselves by 

 their mouth parts to the leaf and secrete wax, which soon 

 fills the space between the leaf and the body of the insect. 

 There are several broods in the course of the season. Its 



