THE BOOK OF THE PEONY 



pathologists who have reported on the disease. 

 It is very probable that we have under the name 

 of root rot several different diseases. They are 

 very likely due to fungi or bacteria, though 

 Winter injury may sometimes be responsible. 



Control. — Removal and destruction of dis- 

 eased roots and the planting of peonies on other 

 land are the only suggestions to be made with our 

 present knowledge of root rots. 



Diseases of the Stem, Leaves, and Flowers 

 The Mosaic Disease. 



So far as I am aware this is the first record of 

 this very peculiar and interesting malady of the 

 peony leaf. I have observed this disease now for 

 several seasons in the peony plantation at Cornell 

 University. It has doubtless been observed by 

 others, and is probably of wide distribution. It 

 does not appear to be a serious malady. 



Symptoms. — The symptoms are very strik- 

 ing. Usually only one or two stalks in a cluster 

 are affected. The leaves show rings of concen- 

 tric bands of alternating dark and light green 

 color. The spots are sometimes large, with broad 

 bands; in other cases small with narrow bands, 

 the spots densely crowded over the leaf. I have 



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