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tion of this apparent white meal is examined under a microscope, 

 it will be found to consist of numerous upright branches, each bear- 

 ing a dense cluster of spores or reproductive bodies at its tip. 

 These spores when ripe are carried away by wind or rain, and those 

 that alight on peony stems germinate on the surface. The germ- 

 tube penetrates the stem and forms a mycelium in its interior, from 

 which a crop of spores is eventually formed on the surface, the 

 time required for this development varying from six to ten days, . 

 depending on the amount of moisture and temperature present. 

 This condition of things continues throughout the summer — that 

 is, if the diseased plants are not promptly removed and burned. 

 When diseased stems are nearly dead, the fungus ceases to produce 

 the kind of fruit described above, but the mycelium present in the 

 cortex, or outermost portion of the stem, becomes resolved into 

 myriads of very minute brown nodules called sclerotia. As the 

 diseased stems decay, these sclerotia are deposited on the soil, where 

 they remain in an unchanged condition until the following spring, 

 when they give origin to several slender branches, each of which 

 bears at its tip three or four chains of very minute conidia. At 

 maturity the conidia forming these chains separate from each other, 

 and further, each conidium is capable of germinating and forming 

 a mycelium; and if this germination occurs in contact with a young 

 and tender stem of a peony just above the ground line, infection 

 takes place and the summer form of the fungus quickly follows." 



Professor Massee goes on to state that the heat of manure is 

 sufficient to encourage the growth of these summer spores, but as 

 only sclerotia are usually formed on dead matter, the manure con- 

 tains large quantities of sclerotia. When fresh manure is use 1 

 freely over the peony beds, these sclerotia are brought in contact 

 with the young stems as they push through, and infection easily 

 follows. 



The following preventive measures are suggested: 



" Remove and burn all drooping stems the moment the first symp- 

 toms are observed. 



" Where the disease has previously existed — or better, under 

 any circumstances — remove the surface soil early in spring, and 

 replace with fresh soil mixed with cjuicklime. 



" Do not use green manure as a top dressing. 



" The mycelium of the fungus is not perennial in the root of the 

 peony, so that the latter starts life perfectly free from its enemy 

 each year, and can only become diseased through inoculation from 

 sclerotia lying in the soil, from germs contained in the manure, or 



