. Pig- 53- Occurrence of stern mst (Fuccinia f;raminis) and leaf rust (Puccinia simplex) of barley during I92I. Net blotch caused by Helminthosporium teres Sacc. Helrninthosporium teres was observed in eleven states: Nev/ York, Illinois, Michigan, Wisconsin, I'innesotaj North Dakota, South Dakota, Montana, Colorado, Oregon, and California. Melhus estim;^ted that the net blotch reduced the yield in lov/a by Evans reports that he had seen a dozen fields in South Dakota in which this disease had completely ruined the crop, and he estimates the reduc- tion in yield for the state at 3%- The maximum

This image is a public domain image, which means either that copyright has expired in the image or the copyright holder has waived their copyright. Alamy charges you a fee for access to the high resolution copy of the image.

This image could have imperfections as it’s either historical or reportage.

. Pig- 53- Occurrence of stern mst (Fuccinia f;raminis) and leaf rust (Puccinia simplex) of barley during I92I. Net blotch caused by Helminthosporium teres Sacc. Helrninthosporium teres was observed in eleven states: Nev/ York, Illinois, Michigan, Wisconsin, I'innesotaj North Dakota, South Dakota, Montana, Colorado, Oregon, and California. Melhus estim;^ted that the net blotch reduced the yield in lov/a by Evans reports that he had seen a dozen fields in South Dakota in which this disease had completely ruined the crop, and he estimates the reduc- tion in yield for the state at 3%- The maximum percentage of the disease which he found in any one field was 100. The disease also v/as destructive in certain localities in Oklahoma as is indicated by the follov;ing memorandum from Dr. H- B. Humphrey to Dr. G. R. Lyman: (Referring to specimens from Robert Stratton, station plot.) "Specimen No. 7 consists of barley plants affected with net blotch. These specimens represent an unusually serious attack and if they are representative of the condition of the barley field from which they were taken, my recommendation would be to plov/ the whole thing under, in order to avoid the possible further spread of spores from such diseased material. Helrninthosporium teres, as you know, has its perfect stage in a species of Pleospora." Net blotch evidently was unimportant in the other states from which it was reported; only in lov/a, South Dakota, ard in some localities in Oklahoma v/as it really destructive.