QIQ JOURNAL OF FORESTRY 



fairly good cover of annuals composed chiefly of species with hard 

 seeds which lived through the fire either in the soil or in the litter 

 itself. Much of the area was completely stocked with these annuals 

 wdiich form a most excellent protection against erosion. Where erosion 

 is at all serious few plants and few species are found, the number 

 present being largely controlled by the amount of erosion. That the 

 seeds were in this finer material which was carried away by the first 

 storms cannot be doubted, as the same species found on the slopes 

 were obtained from the first alluvial deposits at the mouths of the 

 draws, mixed in with fine leaf mold, litter, and soil. 



The flow of the streams shows the same characteristics during the 

 later storms as at first. There is a very sharp rise in the peak, a 

 decidedly sharp fall, and a relatively low high-water stage following. 

 From the areas with a brush cover the rise is not so steep, the fall 

 is not so rapid, and there is a longer period of high water. Through- 

 out the winter the water at the normal daily discharge from the 

 burned lands was exceedingly dirty and samples of the water collected 

 at flood heights in Dalton Canyon after light storms m March, 1920, 

 show that as high as 90 per cent by volume was soil and only 10 per 

 cent water. The percentages were determined by settling for ten 

 days in pint jars. The total amount of sediment thus carried during 

 the winter is beyond computing; and it is worthy of note that the 

 same kind of litter and silt carried out from the burned areas was 

 found in the San Gabriel River at the ocean, so that a large part of 

 this most fertile material was carried to the harbor as well as being 

 deposited in the overflowed lands during the high-water stage. 



The deposits at the close of the rainy season showed that the bulk 

 of the material had eroded from the steeper slopes and deeper soils 

 and that as the season progressed coarser material and larger sized 

 particles were being moved. A larger number of landslides were 

 started and the shoe-string type of erosion was common everywhere 

 on the slopes. Gullying by cutting and undermining was prevalent in 

 many of the small dams, which will result in the lowering of the 

 water-table- and lead to still further erosion. The first of March it 

 was estimated that 50,000 cubic yards of material had been moved 

 from the Little Dalton Canyon since the fire and this figure was 

 probably increased by the subsequent storms. The check dams built 

 in the canyon were filled to capacity, and the original gradient of the 

 stream re-established, but at an increase in height of about three 



