Bean Axthracxose. 287 



Removal of diseased seedlings. — In preparing the first bulletin on 

 this subject, the writer found that several investigators of this disease 

 had recommended the removal of diseased seedlings. Theoretically 

 this would undoubtedly be effective, but it is absolutely impracticable 

 except in short garden rows, and even then, as the writer has since 

 satisfied himself many times, only an expert would be able to do effective 

 work in removing them. Even if it were possible for the ordinary work- 

 man to recognize every diseased seedling, it would be an endless and 

 almost impossible task to go over large fields. Their removal, therefore, 

 may be entirely disregarded as a factor in controlling this disease. 



Spraying with Bordeaux mixture. — Several investigators have reported 

 remarkable results from spraying with Bordeaux mixture. After three 

 seasons* observations in large bean fields where the most up to date 

 machinery is used, machinery particularly adapted for the bean crop, 

 the writer is forced to the opinion, that spraying with Bordeaux mixture 

 is, to say the very least, unprofitable. It appears to be not only unprofit- 

 able, but entirel}^ ineffective in reducing the anthracnose. In bean 

 fields, side by side, one sprayed and the other unspra^^ed, grown from the 

 same seed on soil almost identical, anthracnose has been equally destruc- 

 tive. On the other hand, experiments conducted by the writer on a 

 few rows of beans in experimental plots, have apparently shown that 

 if thoroughly and properly applied, Bordeaux mixture is effective in 

 controlling the disease. The difficulty in the field, therefore, seems 

 to be that the present machiner}^ does not effectively cover the parts 

 of the bean plant that must be covered with the poison. If the disease 

 is to be controlled, not only the upper surfaces of the leaves, but the 

 stems and pods must be coated with the Bordeaux. We have been unable 

 to find a machine that will do this, after the beans have formed any 

 considerable top. Until a machine is put on the market that will 

 cover the stems and pods at any stage in the growth of the plant, little 

 or no results can be expected from spraying. It is stated in the bulletin 

 that three sprayings will be sufficient. Some growers have sprayed 

 their beans almost weekl}' throughout the season, but neither they 

 nor the writer could see any material results from the sprayings. 

 At the bottom of page 208, we find the statement that the writer "has 

 shown that one or two thorough sprayings, even if a large percentage 

 of the plants were badly diseased, will insure a clean and profitable 

 crop." He still stands behind that statement, but would point out, 

 that this was on small experimental rows where the work could be care- 

 fully done. That it may be possible to control the disease by spraying, 

 even under field conditions, the writer will grant. More than that. 



