raspberries, but not often injurious to the red varieties. It is detected by the circular or elliptical gray scab-like spots on the canes. Avoid taking young plants from diseased plantations. Remove all old canes and badly diseased new ones as soon as the fruit is gathered. Although spraying with bordeaux, 5-5-50, will control the malady, the treatment may not be profitable. If spraying seems advisable, make the first application when the new canes are 6 to 8 in. high and follow with two more at intervals of 10 to 14 days.
Cane-blight or wilt is a destructive disease affecting both red and black varieties. Fruiting canes suddenly wilt and die. It is caused by a fungus which attacks the cane at some point and kills the bark and wood, thereby causing the parts above to die. No successful treatment is known. In making new settings, use only plants from healthy plantations. Remove the fruiting canes as soon as the fruit is gathered.
Red-rust is often serious on black varieties, but does not affect red ones. It is the same as red rust of blackberry. Dig up and destroy affected plants.