496 



which have reached maturity, as the fungi very rarely produces any 

 spores on such berries. 



It is a matter of common observation among growers that some 

 varieties rot or scald worse than others. Hence, in setting new bogs 

 or replanting old ones the most hardy varieties should be used. By 

 giving careful attention to the selection of disease-resistant plants for 

 propagation, a practically immune variety can probably be event- 

 ually secured. (F. B. 221.) 



Summary. The cranberry blast, scald, and rot are caused by 

 parasitic fungi. Spraying experiments have demonstrated that these 

 diseases can be controlled by a proper application of Bordeaux mix- 

 ture. To make the mixture effective it must be carefully prepared 

 and thoroughly applied, with the addition of resin-fishoil soap or 

 some other spreading and adhesive mixture. Careless or partial 

 spraying is worse than useless. At least five applications should be 

 made during the season. No interval of more than fifteen days 

 should elapse between the applications. The last application should 

 not be made earlier than August 15. It is necessary to use at least 

 four barrels per acre at each spraying. The fruit and vines must be 

 thoroughly covered in order to protect them. The barrel and cart or 

 barrel and wagon spraying outfit, with two 20-foot lengths of hose, 

 has been found most satisfactory. The cost per acre for spraying 

 five times during the season should not, according to the methods 

 described here, exceed $15. (F. B. 221.) 



CURRANT DISEASES. 



Leaf-Spot of Currants. This is referable to two species of fungi 

 (Septoria ribis; Cercospora angulata) of which only the Septoria has 

 been discovered in Ohio. These fungi produce early spotting and 

 premature dropping of the currant foliage; in some instances the 

 leaves drop even before the fruit has ripened. Bordeaux mixture 

 applied is effective against this disease, though late applications may 

 render it necessary to wash the fruit. For this reason, if for no 

 other, the first application should be made very early and followed 

 by about two more at fortnightly intervals. 



Rust. A rather common rust fungus (Puccinia ribis) has been 

 discovered upon currant. Warning has been recently sent out 

 against a second fungus (Cronartium ribicplum Peridermium stro- 

 bi) which attacks the seedlings of white pine in the aecidial stage, 

 and passes its uredo and teleuto stages upon the leaves of currants 

 and gooseberries. This fungus is to be sought for with care since 

 its occurence in the United States may have niuch to do with the 

 success of forest plantings of white pine. (Ohio E. S. B. 214.) 



Cane Blight. The first effects of acute disease in the plant are 

 seen in the wilting of the foliage, and the premature coloration of 

 the fruits. The leaves turn yellow, dry up and fall away. The fruit 

 clusters on affected plants and usually much smaller and more thinly 

 fruited than on healthy ones, while the berries are colored prema- 

 turely, shrivel and fall away with the leaves, so that the canes are 

 barren. The latter then die rapidly and soon dry up. Frequently 

 the central canes of the bush die in the manner described, while the 



