1G4 AOmCULTUKAL ArPKOPRIATIOX BILL, Hr24. 



ditions and heavy infestation, it lias led a good many wheat growei-s 

 to beliovo it is. 



IMr. AxDKRsoN'. Well, I think that is partiallv responsiMe for the 

 fcehng on the ])art of some farnuTs that the barhorrv (Tathcation has 

 not produced results. In otlier words, they make no distinction 

 whatever between black rusts and red rust. It is all rust and if they 

 get this red leaf rust and it spoils the crops or damages them, they 

 make no (hstinction with regard to that at all. They just assume 

 that the eradication of the barberrv has failed to eliminate rnst. 

 That is my impression as to one of the reasons why tlu^ farmers are 

 more skeptical about the relation ])etween bjuherry and rust than 

 thev would be otherwise. 



Doctor Kellermax. I think that is true, Mr. Chairman. There is 

 one thing further. It is not only a different species of rust, but other 

 totally different species are considered by them as stem rust. I 

 know that farmers have considered wheat scab, which does not show 

 any of the same symptoms except that you get your swiveled grain, 

 as rust of wheat scab infections. I know that many farmers have 

 said all of the time that it was nothing but stem rust or black rust, 

 and as such they have actually considered it. when there was not 

 any black rust on their plants at all. And there is a very grent 

 confusion of ideas about these different diseases, but no disease has 

 sho^^^l the epidemic character of the black rust. There is no disease 

 of wheat that we have now that has been able to destroy such enor- 

 mous areas of grain in such a short time as during the 1914 and 1010 

 epidemics of l3lack stem rust. There have l)een. it is true, hx-al 

 epidemics even in areas that have been reported as cleaned up during 

 the past year. As far as I am aware, every one of those areas has 

 on reexamination been found to have been not perfectly cleanctl. 

 There is scattered an occasional barberry. 



Mr. Andersox. Has it been definitely demonstrated that if we get 

 rid of the barberries there is not some other plant on which this stuff' 

 will winter over? 



Doctor Keli.erman. Not north of the Nebraska line. I tlank that 

 it is safe to say that in the average winter the spores will not live 

 over on other plants. In the southern plains several species of native 

 grasses will carry the rust over winter, but in the Northern areas 

 that we commonly refer to as the spring wheat areas black stem 

 rust can over-winter only on the leaves of the common barberry. 

 There are two or three species of barberrv and of nndionia that can 

 carry the rust over winter; these are nil used only as ornamentals. 

 Generally speaking, the common barberrv is the only plaTit that has 

 been widely used and the only one that has been planted under such 

 conditions that it is beginning to s])rei'.(l as a wild |)lant From tlu> 

 standpoint of the rust-control camj)aign, therel\)rc, the comnion bar- 

 berry is the only important factor. 



Mr. BrcHAN.VN. Is that the north Nebraska line ^ 



Doctor Ke[j.f.kmax. Yes; the sju'ing wbcat area sliown on this 

 map [iiulicating] will have enidemics of black stem rust if the barberry 

 is not completely eradicated. In the South the riist will winter over 

 on native grasses, but, as you know, black stem rust is not a very 

 serious facloi" on wiiiter wheat. 



Mr. JU'cnANAN. "^'ou say thut you \V(Uild not lind over-wintering 

 spores north of the Nebraska line < 



