FUNGOUS DISEASES. 65 



The Lecturer said that the Htmus paper method in the ground 

 was not rehable. A somewhat better way was to make an aqueous 

 extract of the soil by mixing it with water and after letting it settle 

 then apply the litmus paper test to the liquid. 



He said that an acid condition of the soil is unfortunate for many 

 plants. It should be more nearly neutral but what its condition 

 should be with respect to fungous disease depends upon the specific . 

 disease that is being treated. 



Robert Cameron asked concerning the diseases of the hollyhock 

 and aster. 



The Lecturer replied that the copper solutions are serviceable, 

 but objectionable, and that extensive experiments were now being 

 tried for the treatment of rust, the chief hollyhock disease. In 

 regard to the stem disease of the aster he said it was quite difficult to 

 prevent. It was caused by fungi gaining admittance to the plant 

 through the soil or through some injury to the stem. Destruction of 

 the infected stock was recommended and thorough aeration and 

 cultivation were the best remedies. Also sterilization of the soil 

 in the seed bed was advantageous. 



In answer to a question regarding the wilt of the melon the Lec- 

 turer said that the common wilt or bacterial disease of the melon 

 begins frequently before the plant has begun to blossom and spreads 

 rapidly. The leaves become affected, wilting and dr}ing up. 

 No effective remedial measures have yet been found. He advised 

 destroying the old diseased parts, for the bacteria may be carried 

 over the season in the soil. Seed selection from resistant hills 

 should be practiced where practicable. 



R. W. Curtis spoke of the peony disease which was causing much 

 trouble to peony growers. The Lecturer said that there may be 

 several peony diseases. Very few data are available at present, but 

 peony diseases are now receiving special attention by Prof. Whetzel 

 in the experimental plots at Cornell University. 



The question was asked as to the value of Bordeaux mixture as a 

 remedy for the asparagus rust. 



The Lecturer replied that Bordeaux mixture as a spray was 

 effective if used properly and with the right kind of apparatus for 

 spraying, but that the expense was large. Replying to an inquiry 

 concerning diseased roots, he said that asparagus rust ordinarily 



