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CALIFORNIA FRUITS: HOW TO GROW THEM 



cot, the olive tuberculosis, etc., are instances. Cutting back to 

 healthy wood (with tools dipped after each cut in corrosive subli- 

 mate, one part to one thousand parts of water), and burning all 

 removed parts is the best treatment which can at present be pre- 

 scribed. 



The walnut blight, demonstrated by Newton B. Pierce, of Santa 

 Ana, to be caused by a bacterium, has so far resisted treatment. The 

 disease is recognized by black sunken spots on the hull of the young 

 walnut; generally worst at the blossom end and usually first seen 

 there early in the season ; later the spots run together and encompass 

 considerable areas of the surface. As the disease progresses the nut 

 is transformed into a hateful black mass and is utterly destroyed. 

 The disease also affects the leaves and young wood. The recourse 

 seems to be toward resistant varieties, as stated in the chapter on 

 the walnut. 



Lemon Rot, a fungus disease destructive to the fruit in the 

 orchard and during curing or in transit, is fully expounded in Bul- 

 letin 190 of the University Experiment Station. 



Crown knot on peach just below ground. 



