52 BULLETIN 1294, U. S. DEPARTMENT OF AGRICULTURE 
Sample plots on burned ground showed that trees up to 6 feet in 
height were uniformly destroyed, and the reproduction, considering 
the area as a whole, is more patchy in its distribution as a result of 
this fire. The thinning of the smaller individuals is not of itself 
undesirable and may at times even be a benefit, but it was in these 
dense stands that the increase in the amount of litter since the fire 
was most striking. 
This fire reemphasized the conclusion previously reached on the- 
Lassen County burn that reproduction standing in squaw carpet is 
practically immune to light surface fires, because this low-spreading 
plant is sufficiently fire resistant to stop the progress of such fires. 
The most striking contrast between the Lassen County and Sierra 
County burns is in the direct and indirect costs. On one area, heavy 
cash investments in protecting merchantable timber were completely 
successful in eliminating damage to this class of material. On the 
other area, with no investment in protection of merchantable timber, 
material loss to mature trees resulted. 
DETAILED STUDIES OF HAZARD REDUCTION—SHASTA AND SISKIYOU COUNTIES 
An experimental light-burning area in Shasta County, in the mixed 
conifer type, was burned in March, 1911, with an exceptionally light 
fire, burning only the top layer of the litter and killing much of the 
reproduction without consuming it (22). The clumps of brush in 
the burned area were also killed by the fire, but again without con- 
suming the stems, twigs, or even the foliage. This experiment cov- 
ered only a few acres and was so small that no effort was made to 
study the effect of the burn on merchantable timber. Instead, efforts 
were concentrated in determining the effects on reproduction and in 
reducing inflammable material. Periodic examinations were made 
of the condition of litter, brush, and general inflammability on a 
number of detailed plots set out on the burn, the results of which 
are given in the following paragraphs: Within a year following this 
light surface fire the inflammable material had reached its original 
amount and it contimued to increase during the period of the experi- 
ment. This feature of light burning has appeared so uniformly that 
it can only be regarded as an inherent result of a surface fire. 
Examination of March, 1911, directly after the fire 
Condition of litter.—Where less than one-half inch deep, all the litter was con- 
sumed, but where deeper only the top layer burned. 
Condition of brush.—Killed and partly consumed, but much of it retaining 
scorched leaves. 
Degree of hazard.—Amount of inflammable material much reduced, to the extent 
that fire could not have spread again at this time. 
Examination of October, 1911, six months after the fire 
Condition of litter.—Amount now equal to that on adjoining areas, produced by 
dead vegetation, mainly fire killed. 
Condition of brush.—New sprouts varying from 10 to 20 inches. ~ 
Degree of hazard.—Amount of inflammable material now equal to that before fire. 
Examination of August, 1912, approximately 18 months after the fire 
Condition of litter.—Very heavy under dense sapling stands; moderately heavy 
elsewhere. 
Condition of brush.—Sprouts now 24 to 36 inches long. 
Degree of hazard.—As before, or slightly increased, with half of needles still 
hanging on fire-killed reproduction. 
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