ISiEVV YuKK A'JlliCL'LTUUAL Exi'EUKMKXT STATION. 1 oO 



down the hill on the new bed the plants were naked and gray- 

 black with Dariuca and the winter stage of the rust. As in all 

 the other fields both stages of the rust were found. The peculiar 

 belts of brown plants with little foliage, yellowish-green plants 

 with some foliage, and last the green plants showing very little 

 rust, all following the contour of the hill and not limited to the 

 new bed, were verv marked. If these belts had been limited to 

 the new bed and to only a small portion of the old bed adjoining, 

 all the conditions might be accounted for by assuming that the 

 rust had started early in June on the new bed and had gradually 

 spread to the older bed after the cutting season was over. If 

 the new bed had been so situated that prevailing winds could 

 carry the rust to the older portion of the field, the conditions 

 found could have been considered the result of the rust starting 

 early on the new bed and spreading in curves by aid of the winds. 

 As a matter of fact the rows run east and west, and the contour 

 lines of the hill extend from south to north northwest, the slope 

 being east northeast. The new bed is on the east end of the field. 

 The slightly rusted portion of the field was on the crest of the 

 knoll. Undoubtedly the rust had attacked the new bed early in 

 the season, but this would not account for the rust belts follow- 

 ing the contour of the hill and infecting the old bed on the north 

 side. It was said that the rust affected the field in the same man- 

 ner the previous year. 



As far as known there are no tests showing that it is abso- 

 lutely essential for the spores of the summer stage of the rust 

 to have a nidus of water in which to germinate under natural 

 conditions. It is an assumed fact among pathologists that the 

 spores of all kinds of fungi, including the rusts, require drops 

 of water in which to germinate. Water certainly is required tj 

 germinate them under artificial conditions. If this is a correct 

 assumption, then the fact that an abundance of moisture had 

 been furnished for the germination of the rust spores in the form 

 of dewdrops, might account for some of the conditions found in 

 the above field. Now it is often observed that low lands and 

 those adjoining streams get heavier dews than does the high 



