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mains bare of vegetation through the first season following the 

 intense heat of a high brush pile. During the next season one is 

 likely to find certain members of the moss group starting their 

 invasion near the periphery, and possibly small scattered colo- 

 nies starting in other portions. Frequently a few discomycetous 

 fungi are also found. These are usually scattered about the in- 

 terior of the circle. A close inspection may even disclose members 

 of other divisions of the fungous group. 



Among the early invaders one will usually find such moss 

 genera represented as Bryum, Ceratodon and Funaria, with 

 possibly Polytrichum as a later arrival in dry localities. Among 

 the fungi one would naturally expect to find Pyronema confluens 

 appearing as the most common example. Such others as Asco- 

 bolus carbonarius, Geopyxis cupularis, Peziza pustulata, Peziza 

 violacea and Rhizinia inflata may be encountered, and there is 

 always the chance of making new acquaintances. 



The following season the mosses usually become more gen- 

 erally dispersed over the plot, and flowering plants may begin 

 their invasion. This latter naturally begins near the margin of 

 the area, where the effect of the fire has possibly not been so 

 great. A few casuals may be seen among the earlier moss patch- 

 es in the inner portion. It must be recognized, however, that 

 any sequence of events is easily altered by varying conditions 

 of locality. 



With different soil, moisture, acidity and temperature factors 

 retardation or hastening of plant development may be expected. 

 These factors also regulate the sequence in the series of plants 

 to develop prior to reestablishment of the pre-fire state. An 

 open sand or compact clay soil, a naturally dry or damp situa- 

 tion, a hollow, a knoll or a sloping hillside will each tend to 

 induce variation. Sufficient moisture and adequate drainage 

 are important aids in hastening re vegetation, provided they 

 operate in proper conjunction with one another. 



Seaver and Clark 2 and Seaver 3 have shown that intense heat 

 may materially increase the soluble matter in the soil, and that 

 flowering plants may be retarded in their growth by this con- 



2 Seaver, F. J. and Clark, E. D. Biochemical studies of soils subjected to 

 dry heat. Bioch. Bull. 1: 413-427, pi. 7. 1912. 



3 Seaver, F. J. North American Cup-fungi. 1-284, pis. 1-45+figs. 1-15. 

 1928. 



