74 Halsted ; Mycolooical Notes 



It is seen from tliis that in a field when the diseased roots out- 

 weigh the sound ones, the presence of hme in tlie soil has the 

 wholesome effect of reducing the disease to near four per cent, of 

 its abundance upon untreated land. 



It should be said in addition that under the method of inspec- 

 tion any root that showed the slightest indication of the club-root 



group of sound specimens and, 

 therefore, this was a discrimination against the treatment, for the 

 diseased roots grown in the limed land were usually only infested 

 to a small extent, while those upon the untreated soil were, as a 



rule, badly diseased and frequently offensive and of course unmar- 

 ketable. 



fungus was excluded from the 



■tijicial Introduction of 



Smut-infested soil was 



obtained from a field of a large onion grower in the southern part 

 of the State where Urocystis ccpulac Fr., had been so fatal that 

 the growing of onions was abandoned. The dry soil thus obtained 

 was added to the open row before the onion seed had been sown 

 and an equal amount upon the covered row, making in all one 

 bushel of the soil to the belt or at the rate of 1 20 bushels per 

 acre. The seed was sown upon April 23d, and owing to unfavor- 

 able weather, germination was slow and the smutted seedlings 

 were first found upon June 8th, and in abundance ; but only in the 

 belt where the soil had received the earth from the far away old 

 onion field. A white variety " Pearl " and a red variety " Red 

 Weathersfield " were in alternate rows, and there seemed to be no 

 difference in susceptibility between the two kinds. No smutted 

 onions were found outside of the belt under treatment, which indi- 

 cates that the disease does not spread rapidly over the field unless 

 the soil is transported, which may be by implements of culture, by 

 winds or the flow of water over the surface of the soil. It is 

 demonstrated that the smut germs can be artificially transferred, 

 very effectively, in small amounts of soil and onion growers should 

 bear the fact in mind in contending with this serious enemy. 



if Blight as a Test f 



The beet has 



been grown in the Experiment Area for the past five years, and is 

 found with us to be one of the best plants for testing of fungicides. 

 There are two fungous diseases that infest the foliage in particular 

 and one of these, Ccrcospora bcticola Sacc. is so abundant as fo h^ 



