ROLE OF FIRE IN CALIFORNIA PINE FORESTS OT 
TABLE 12.—EHffects of light fire on young growth 
[Sample plots covering 14,725 square feet (0.338 acre), Sierra County, 1921] 
Diameter of trees breast high | Total killed Total alive 
| 
| Number | Per cent | Number | Per cent 
Undermezinehes'(secdilings) 2). 22 Nooo. ea Cee ee | 427 97 14 
DANCES same eaae wet rey eos se b5 a ee a ae Re ae | 163 | 88 | 23 | 37 
GUT) CHES yee cree EONS aL ee eh a 38 | 63 22 | 36 
CUD ae) AVI E Ss pee as MAR 2 ole Pee SM ie aie Be 8 OSE emee, ethaus «(pias Om Le 22 37 | 38 | 67 
HinieG ese mmemecne nates. Us A oe es Bel ee 10 33 20 | 23 
GY TI GLVGS oes eee eee terete ee Se a SE es ee Je 3 18 | 14 2 
We II CICS peat ee eee eerie SMa UENO eo ee eee ee ee 0 0 ff) 100 
Si imch ecm secre ewe eam eee as! Ok de ot Ses 2 33 4 | 67 
Quin Gh esses eee eat com aad ee ol ee ain whe Ws see 0 0 9 | 100 
PRU) TS Lp a a RS ae Ne | 2 pe a 0 0 4 | 100 
A iG Re Sa eee ener ae eens les ye dete a eed Lt | 0 0 2 | 100 
TPIT) ea Se = 15 Head see ee mp ms | 0 0 6 | 100 
SUSIE a Es aa alsa) ee ae Ae an 665 | 80 163 | 20 
A similar condition was found on the Red River burn. Here, 
as shown in Table 13, the seedlings were almost completely wiped 
out; but a greater and greater percentage of the trees survived as 
the size increased. On the area of the plots, covering a little more 
than a fifth of an acre, 22 per cent of the young trees lived, an 
equivalent of 676 to the acre. Because of the good distribution and 
the fair amount of living reproduction, the fire had been beneficial or 
at least neutral in its effect on reproduction. On this, as on the area 
previously described, not all the land within the exterior boundaries 
of the fire was covered by the flames. 
TABLE 13.—Effect of light fire on young growth of western yellow pine 
{Sample plots totaling 9,000 square feet (0.207 acre) in area, Lassen County] 
Diameter of trees breast high Total killed Total alive 
e Number | Per cent | Number | Per cent 
Wrder2 inchesk(Scedlin gs) see eet! ARE EAE eke 222 97 8 | 3 
Du OS eee eee Be ge Wee a 188 78 53 | 22 
SY GHEE eee Dh a ee ea A i ea ee 53 | 55 43 45 
AINGNGS= = = aoe eee MOOt ete tes) Mee boot Soto 14 | 45 17 55 
Bh hag Ss SE 2 Rag ecg > eee ee re 7 44 g 56 
GuNiChes feat eS Pa i a 5 OE BIRR ries 2 Ea actibes cates 1 25 3 75 
Ze Mba Ga ght se a EBS SS 2c ae Ly gil i ae Oe era) 2a nk ge ed 3 | 43 4 | 57 
Rin chesuee eee eee ae ey ee ee a hp eae Se 0 | 0 | 3 | 100 
Sop al resent MOON Se oe ep 488 78 | 140 22 
With summer fires, these dense groups of reproduction, even in the 
sapling and pole stages, are peculiarly ee to crown fires, just 
as the larger second-growth stands are. Hven where the thinning 
effect of leks fire is apparently beneficial, basal scars are formed on 
many of the surviving trees, as shown on the areas already cited. 
There can be little doubt that these scars are likely to prove a source 
of weakness during the life of the trees. 
RELATIVE SUSCEPTIBILITY OF VARIOUS SPECIES 
In a plot on the White Horse burn, Modoc National Forest, in a 
mixed stand of reproduction, all the species were intermingled, and 
the trees were less than 4 inches in diameter. The data given in 
