5io Bulletin 283. 



weeks. Japan plums should not be sprayed with Bordeaux. Geneva Bulletins 

 98 and 117. 



POTATO. 



There are different kinds of potato blights and rots. The most 

 Blight and rot. important are early blight and late blight — both fungous dis- 

 eases. Early blight affects only the foliage. Late blight kills the 

 foliage and often rots the tubers. Two serious troubles often mistaken for blight are : 

 (i) Tip burn, the browning of the tips and margins of the leaves due to dry 

 weather; and (2) flea-beetle injury, in which the leaves show numerous small holes 

 and then dry up. The loss from blight and flea-beetles is enormous — often one- 

 fourth to one-half the crop. For blight, rot, and flea-beetles, spray with Bor- 

 deaux, 5-5-50. For addition of insect poisons see potato ,flea-beetles. Com- 

 mence when the plants are 6 to 8 inches highland repeat every 10 to 14 days 

 during the season, making 5 to 7 applications in all. Use 40 to 100 gallons per 

 acre at each application. Under conditions exceptionally favorable to blight 

 it will pay to spray as often as once a week. Geneva Bulletins loi, 123, 221, 

 241, 264, 267, 279, 290 and 311. 



Scab is caused by a fungus that attacks the surface of the 

 Scab. tubers. It is carried over 



on diseased tubers and in 

 the soil. Treat tubers before cutting by soak- 

 ing in formalin solution, i pint to 30 gallons 

 water, for 2 hours, or in corrosive sublimate, 

 I oz. to 7 gallons, for ij hours. Plant in 



/ 



clean soil. In general, when land becomes MB^TS..- "" ,«s -^ 



badly infested with scab it is best to plant it f^'^>i%^ 



with other crops for several years. Vermont • ' 'S^^ 



Bulletin 85 and IMaine Bulletin 141. 



QUINCE. 

 T £ J T-i 'i This is a fungous disease 



Leaf and Fruit p^^^^^i^g round, reddish 



P ' brown spots on the leaves 



^' °' and fruit. Spray three times ^ 



with Bordeaux as for apple and pear scab. 

 Cornell Bulletin 145. Fig. 220. Fruit spot on quince. 



RASPBERRY. 



Anthracnose is very destructive to black raspberries, but not 



Anthracnose. often injurious to the red varieties. It is detected by the circular 



Fig. 222. 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, it may not be profitable. 



If spxaying seems advisable, make the first application when the new canes are 6 to 



S inches high and follow with two more at intervals of 10 to 14 days. Geneva 



Bulletin 124. 



