244 AGRICULTURE ON THE PACIFIC SLOPE 



to tree by bees and other insects which visit the flowers. 



^ The disease 



tjlk may enter 



||\ / through small 



I ^tiHUtafc* branches such 



JB B^B B^ as the infected 



1^, M| A one shown in 



y^ WlA B^^S I fi S ure 142 - 

 yP^ ^r The only rem- 



edy is to cut 

 out and burn 

 all diseased 

 twigs, disin- 

 fecting all the 



FIG. 143.-Walnut blight on leaves. t()olg ^^ 



with a 5 per cent solution of carbolic acid. (Idaho 

 Experiment Station, Bulletin 39; 

 Utah, 65; Washington, 83.) 



WalnuLJ)light. This is also 

 caused by bacteria. It makes 

 black cankered spots on the 

 young nuts and causes them to 

 fall early or makes the kernel 

 decay. In bad cases the twigs 

 are also killed. (Oregon Exper- 

 iment Station, Bulletin 92.) FIG. 144. walnut blight 



Olive knot. This is due to 

 bacteria which cause swellings or " knots " on the 



