811 



JOURNAL OF FORESTRY 



The difference between the samples is quite striking when compared 

 with the first list. It is readily seen that with the first rain of any 

 consequence, the seeds of herbaceous plants in the surface soil and 

 litter are almost entirely removed from the area, and that there can 

 be no question as to the source of the plants which spring up on 

 the area after a fire. The almost total absence of plants from the 

 eroded and burned area is readily explained, and it is conceivable 

 that more seed is lost by erosion than by the fire itself, though a fire 

 which consumes all the litter probably destroys a large amount of seed 

 through heat action in addition to th^t burned. 



Those seeds which escaped the fire and erosion are heavy seeds, 

 except Brodiiim cicutarium, and have hard seed coats. In addition 

 they were from ten to twenty days later in germinating than the same 

 species from the alluvial fan. The only explanation possible for this 

 phenomena is that these seeds were buried in the surface soil and 

 were seeds from previous years and had been lying dormant for a 

 considerable time, while the seeds found in the washed material were 

 relatively fresh and from plants that had grown in the chaparral stand 

 more recently. 



The character of the soil as to its physical and chemical properties is 

 being made a subject of investigation, as well as the effect of the dif- 

 ferent soil classes upon the rate of growth and development of plants. 



