SPOILAGE OF CRANBERRIES AFTER HARVEST. 7 



caused by Penicillium spp., is rather common on fruit held late in 

 storage, but is usually associated with other rots, and is not of great 

 importance. Ripe-rdt develops at a lower temperature than any 

 of the other rots, except end-rot, and is most frequent in Massa- 

 chusetts. 



CONTROL OF FUNGOUS DISEASES. 

 Bog Management. 



Since all the fungi which cause important storage rots of cran- 

 berries are found on the bogs and in large part gain entrance to the 

 berries before they are picked, control measures should begin with 

 the bog. Not all of the factors which determine the abundance of 

 fungi are understood at present; in fact, it sometimes seems as if 

 a bog is free from rot-producing fungi in spite of the treatment it 

 receives rather than because of its management. Certain phases of 

 bog management seem, however, to have a direct relation to the 

 keeping quality of the fruit produced. An excessive growth of vines, 

 whether produced by too much nitrogenous plant food or some other 

 cause, generally results in diseased fruit. 



Many cranberry growers believe that frequent flooding to prevent 

 injury from early frosts in the fall seriously affects the keeping qual- 

 ity of the fruit, although this is not uniformly the case. The writers 

 had under observation one bog which during the fall of 1917 was 

 completely submerged on 12 nights, and the fruit still showed excep- 

 tional keeping quality. 



If the water is held for a considerable period continuously, how- 

 ever, the result is very likely to be disastrous. Cranberries of the 

 Early Black variety on the Massachusetts State bog, which had been 

 submerged for two weeks after the bulk of the crop was harvested, 

 showed a great increase in the rot of the flooded fruit as compared 

 with the fruit harvested before the flooding. In this case, indeed, 

 a serious infection of Sporonema oxy cocci (ripe-rot) occurred on the 

 berries which had been submerged. Only a few of the berries picked 

 before this flooding were found to be infected with this fungus. In 

 northern cranberry regions during cold periods bogs are sometimes 

 flooded and the water held so long that the fruit may be actually 

 smothered. This practice is certain to injure the fruit. 



The holding of winter flowage until mid-July, thus sacrificing one 

 season's crop, is occasionally practiced in both Massachusetts and 

 New Jersey as a means of reducing pests; this is one of the treat- 

 ments recommended by Franklin (4) and by Scammell (7) for the 

 reduction of several destructive insects. During the year following 

 this treatment a large crop of berries of excellent keeping quality is 

 said to be obtained, and the benefits, both in the reduction of field 

 rot and in the improvement of keeping quality, are frequently said 

 to persist for several years. 



