CHAPARRAL COVER, RUN-OFF, AND EROSION 



811 



feet ; and immense quantities of material moved out to the San Gabriel 

 River. 



To ascertain the effect of the fire on the chaparral a number of plots 

 v^^ere laid out in November, 1919, and examined in March, 1920. These 

 showed the species were rapidly recovering and the number killed and 

 those alive are expressed in per cent in the following table, the data 

 being given for slopes from ],200 to 3,000 feet elevation: 



It is thus seen that there is but slight loss to the stand due to the 

 fire and that the change in composition due to the loss of stools is 

 negligible. The heaviest losses are largely on those slopes where 

 the fire burned the more intensely ; on other slopes the killing was 

 in patches where the fire was intense, as evidenced by the almost total 

 consumption of the stems as against the less severe fire where the 

 stems were merely scorched and the smaller twigs burned. 



The intensity of the fire is probably to have a decided influence upon 

 the rate of recovery. It was yet too early at the time of examination 

 to form more than a hypothesis in this regard. Sprouts were forming 

 and growing, but the rate of growth appeared slow on those stools 

 where the fire had been most severe, and in a number of cases the 

 sprouts formed merely a fuzz. With the close of the present vege- 

 tative period, data on the rate of growth will be obtained as well as 

 the sprouting capacity. 



Some seedling growth was present, and those species which were 

 recf)vering the slowest and witii a higher per cent killed were repre- 

 sented by more ])l.-uUs tlian the others. Erosion, however, played an 

 important part in that many seeds were washed away so that the 



