B OSE SPIN A CH 281 



Control. Steam-sterilize the soil before planting. 

 CLUB-ROOT. See under CABBAGE (p. 266). 



Raspberry. ANTHRACNOSE (Glceosporium venetum). Circular or 

 elliptical, gray scab-like spots on the canes. 



Control. Avoid taking young plants from diseased plantations. 

 Remove all diseased canes as soon as the fruit is picked. Practice 

 frequent rotation. 



CROWN-GALL or ROOT-GALL (Bacterium tumefaciens] . Tumerous 

 outgrowths on the roots, especially on red varieties. It is con- 

 tagious and destructive. 



Control. Never set plants which have galls on the roots. 

 Avoid setting on infested land. See under PEACH (p. 276). 

 RED or ORANGE RUST (Gymnoconia interstitialis) . A dense red 

 powdery growth on the under side of the leaves of black varieties 

 and of blackberries. The fungus hibernates in the roots. 



Control. Dig up and destroy infected plants. 

 Rice. BLAST, BLIGHT or ROTTEN-NECK (Piricularia oryzce). An ex- 

 tensive paling and drying of leaf and stem, and a partial failure 

 of the heads to fill. 



Control. The selection of early maturing varieties is advis- 

 able. Burn stubble and trash left in the fields. 

 Rose. BLACK LEAF-SPOT (Actinonema rosce). Attacks the full-grown 

 leaves, first appearing as small black spots, but later covering 

 nearly or quite the whole surface with blotches. The spots have 

 frayed edges. 



Control. Spray with ammoniacal copper carbonate, beginning 

 with the first appearance of the spots and continuing at intervals 

 of one week until under subjection. 



MILDEW (Sphcerotheca pannosa). A white powdery mildew on the 

 new growth. 



Control. For greenhouse roses keep the steam pipes painted 

 with a paste made of equal parts lime and sulfur mixed with 

 water. Out-of-door roses should be dusted with sulfur flour 

 or sprayed with potassium sulfid, 1 ounce to 3 gallons of 

 water. 



Spinach. There are numerous fungous diseases of this crop, but a 

 practical method of control has not been developed. The best 

 that can be done is to rotate crops. 



