198 Proceedings of Indiana Academy of Science 



barberries in LaGrange, Steuben, and DeKalb counties. In DeKalb 

 County, ten acres of wheat across the road from a heavily infected bar- 

 berry bush were ruined and other fields nearby were badly injured. 

 Wild barberries were found on twelve farms in this county and in 

 every case wheat and rye fields near the barberries were badly rusted. 



Leaf rust {Pncciiiia tHticina) , which is frequently mistaken by 

 growers for stem rust, occurred in epidemic form in southern Indiana 

 this year, and according to Jackson this was the worst outbreak of 

 leaf rust during the last five years. Gregory noted extremely heavy 

 infection in Gibson County and other points in southern Indiana early 

 in June and reports of serious damage were received from Dubois, Vigo, 

 and Jay counties. According to Mains, leaf rust obtained an earlier 

 start than usual, was somewhat worse on spring wheat than on winter 

 wheat, and outside of the barberry areas was much more important 

 than stem rust. Mains and Jackson agreed that very material reduc- 

 tions in yield was to be attributed to leaf rust this year partly because of 

 the extreme severity of the attack itself, and partly because of the fact 

 that the numerous leaf-rust lesions rendered the plants much more sus- 

 cejjtible to serious drouth injury during the hot dry weather of late 

 May and June. Mains reported losses as high as fifty per cent in cer- 

 tain fields, and a seven per cent reduction in yield for the state as a 

 result of this disease. 



Scab caused by Gibherella sdttbitieiii made a late appearance and 

 was not very prevalent this year, although it was slightly more abund- 

 ant than in 1920. Gregory noted very little of this disease. Mains 

 noted only a small amount near Bedford, Lafayette and Wanatah. A 

 trace was noted in Hancock County, and specimens were received from 

 Marion and Putnam counties. 



Rosette occurred only in the experimental field near Wanatah, but 

 its ability to persist thi-ough one season without a susceptible crop and 

 to attack the susceptible wheat variety again the third season was dem- 

 onstrated. The other infested fields were planted with resistant wheat 

 varieties and none of the disease was found. What had every appear- 

 ance of being the true Australian "take-all" disease occurred in two 

 fields on a farm in Knox County. Jackson examined the fields and 

 found the affected plants stunted and the heads not filled out. This 

 condition occurred in patches and in scattered individual plants. A 

 black layer of mycelium was found about the bases of the stems under 

 the lower sheaths and the roots showed evidence of infection. Jackson 

 found characteristic asci and ascospores of OpJiiobolus graminis associ- 

 ated with this disease. 



Forest and Shade Trees. — Burkholder has found great difficulty with 

 evergreens and other trees planted for ornamental purposes in the north- 

 western part of the state because of sunscald and winter injury. The 

 winter climate of Lafayette seems especially severe on conifers, probably 

 due in part to the desiccating eff"ect of the high' winds. The drouth of 

 June and July of this year was also very hard on conifers. During 

 the extreme heat of July there was considerable sunscalding of the 

 foliage of hard maples along city streets. Rhytisma punctatum was 

 found on the leaves of hard maple in Orange County in October as was 



