50 CEANBEERY DISEASES. 



will be continually moist. l)iit not wet, keeps the plants in the most 

 healthy condition. 



DESTRUCTIOX OF DISEASED VINES. 



It is also important that steps should be taken so far as practicable to 

 prevent the distribution and reproduction of the diseases by destroy- 

 ing all dead vines and leaves before the fungi have had opportunity 

 to mature and set free their spores. Small areas of vines frequently 

 die from the attacks of fungi and from other causes. All such vines 

 should be pulled or cut and collected early in the season, at least 

 within a week after the water has been drawn from the vines, and 

 burned. Vines which have been cut in raking bogs to prepare them 

 for scooping should also be destroyed in the same manner ; otherwise 

 the spores of the cranberry fungi develop in great numbers upon them 

 and are a fertile source of infection for the young leaves and fruit. 

 Little is to be feared from full-grown rotten berries, as the fungi 

 very rarely produce any spores upon them. 



SELECTION AND BREEDING OF RESISTANT PLANTS. 



The selection of individual plants showing ability to resist the 

 diseases is also an important means of avoiding them. It is a matter 

 of common observation that some of the varieties are much more 

 subject to disease than others. It may also be noticed that in any 

 badly diseased area of vines there is occasionally one which bears 

 sound fruit. By selecting and propagating these apparently resist- 

 ant plants a variety much less subject to injury could probably soon 

 be produced. 



APPLICATION OF FrNGICIDES, 



After determining the life histories of the most seriouf4 parasites 

 causing the diseases it seemed very probable, judging from their 

 relationships and the manner in Avhich closely related species attack 

 other fruits, that they could be successfully combated by the applicr.- 

 tion of fungicides, the same as their relatives were. Experiments 

 and tests of fungicides have l)een conducted for the past four year-. 

 Several kinds were used the first season, as already mentioned. Bor- 

 deaux mixture applied in the form of a spray proved much more 

 satisfactory than any of the others. Besides these a dust Bordeaux 

 mixture has been used quite tlioi-oughly by one of the cranberry 

 growers, but without any decided benefit. 



110 



