Mycological Notes.— IV 



By Byron D. IlALsria:* 



Mould of the Paconia, — During the last week of May a most 

 remarkable development of Botrytis vulgaris Fr. was met with 

 upon garden paeonias. At that time the plants were in an appar- 

 ently vigorous condition ; they w^ere pushing their flower stalks 

 and the buds beginning to show pink color. While the outer 

 leaves of the clumps were In a healthy condition all the inner ones 

 hung brown and lifeless upon the stems and were overrun with a 

 surprising growth oi Botrytis. 



This fungus is not uncommon upon the old leaves late in the 

 season and the flowers may show it occasionally ; in fact no, 

 2459 ^^ Ellis and Everhart's N. A, Fungi is this species collected 

 upon paeonia petals by Dr. Kellerman. 



In the present instance the fungus was playing no saprophytic 

 role, but flourished as a parasite upon the rank spring herbage of 

 the host and, at the time examined, was spreading upon the outer- 

 most leaves of the clusters. It seems to be a clear case of an un- 

 usual outbreak of a comparatively harmless paeonia fungus de- 

 stroying all the foliage that was not directly in sight, ■ 



The conditions favoring this are the many rainy days that pre- 

 ceded the time of the inspection, there having been eighteen out of 

 the twenty-eight upon which showers had fallen, and the exces- 

 sive cloudy weather — the month up to that time having a record of 

 twenty dark days. 



The wTiter has had no better illustration of the influence of 

 rainfall and consequent absence of sunshine upon fungous growth, 

 for in this case only the outermost leaves exposed to the sun and 

 air were healthful^ while all within the umbrella-like 

 these made were dead or dying and literally covered with a dense 

 growth of conidiophores and the multitudes of spores. The young 

 foliage that otherwise might have been normal was destroyed by 

 the Botrytis that had been highly favored by continued moisture, 

 lack of sunshine and the confinement of the spore-laden air in the 

 interior of the clumps. 



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