TIMBEE GROWlIs^G AlN^D LOGGING PRACTICE IX CALIFOEXIA 13 
One company has recently experimented with smnmer broadcast 
burning of slash on relatively small areas of 5 to 25 acres sur- 
rounded by fire lines, on the theory that the fires would not be de- 
structive if they did not become extensive. Study on the ground 
makes it clear that this, like other forms of broadcast slash burn- 
ing in the yellow pine type, is disastrous in its elfect on the forest. 
A sample strip on this area showed the following effect of summer 
slash fires on advance reproduction : 
Number of seedlings per acre before fire 705 
Number of seedlings per acre after fire 86 
Percentage of reproduction left 12 
Percentage of plots with reproduction, before tire 80 
Percentage of plots with reproduction, after fire 31 
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Fig. 3. 
F- 156377 
-BROADCAST BURNING OF SLASH CREATES BRUSHFIELDS 
Slash fires not only destroy the advance reproduction, but commonly kill many 
seed trees as well, leaving the land to the vigorous invasion of valueless brush 
species. 
Extreme care w^as taken on this area to prevent the spread of fire 
to ^irgin timber, and as a matter of fact, the cost per acre was as 
great as if the slash had been gathered into piles and burned. Never- 
theless, the advance reproduction was nearly wiped out, as illustrated 
in Figures 4 and 5, and this, coupled with the clear cutting, makes the 
future productivity of the area very doubtful. 
The uncertain action of fire is illustrated by another instance, 
where a splendid stand of nearly pure yellow pine has followed 
cutting and broadcast slash burning in the mixed conifer type on a 
north slope. This is one of the unusual cases resulting from a rare 
combination of factors — good seed crop ripened before logging, fire 
removing competing vegetation the same season as logging, and 
favorable subsequent seasons. That such special conditions can not 
be relied on is shown by the adjacent south slope, where the same 
fire resulted in denudation. Several other areas showing favorable 
