NATURAL REGENERATION OF DOUGLAS FIR. 25 
duff. If a fire occurs in this type during a period when there is no 
mature seed in cones on the trees there is little possibility of seed be- 
ing left to restock the area. 
When the loose mineral-soil is exposed it becomes dry, and the 
establishment of seedlings, even in the vicinity of trees from which 
seed is distributed after fire, is very rare. Seedlings which do be- 
come established usually occur under logs or, as has often been 
noted, in the hollows of burned-out stumps, where the moisture is 
retained. | 
Another large burn known as the Two Lakes fire of July, 1918, 
in the upper Cispus region, showed a striking correlation of soil 
conditions and distribution of young growth. ‘The forest floor under 
mature timber in this upper region is quite different from the forest 
floor of the lower valleys. The layer of dry needles and moss was 
completely consumed in the drier localities and the loose, porous, 
ashy soil beneath was severely heated. Stored seed could not sur- 
vive such severe burning, so that what restocking there was had to 
come from seed from the remaining living trees. 
Although 1918 was a good seed year for all of the species of this 
region the condition of the area after the burn showed that the dis- 
tribution of the young growth was not dependent on the remaining 
seed trees. On the other hand, on areas where the entire forest had 
been killed by a crown fire, a consistent relation between the condition 
of the soil and the occurrence of young growth was found. The dry 
slopes and ridges were barren or very sparsely stocked, and the 
moist valleys and north slopes were well stocked. In some places 
there were as many as 40,000 seedlings to the acre. The relation 
between soil conditions and distribution of young growth is shown 
by a typical transect which illustrates conditions on the burn as a 
whole. (Table 11 and fig. 5.) | 
TaBLE 11.—Number of seedlings per acre found on a belt transect one year after 
mature timber had been killed by the Two Lakes fire of July 12-18, 1918o% 
Number of seedlings per acre. 
Chains! distant | 
from green tim- 
ber. Douglas Noble Silver Western Western |Engelmann otal 
fir. fir. fir. hemlock. | redcedar. | spruce.? ; 
1 a pat roo A S20 uae weer see 246 CUA Fea See SOee 80 720 
DES EES ARIS cay areca 80 SOR ree Mae Se SO see neal se 80 320 
Bees tc ullyal eee es A A cat tA I eS a SOM tie eR a 2 80 
CEES ieee eas oa ete PEMD) i Oa aad Ll gts Fe Ease ok ae 80 160 
Os ce eV Ares pe seiner ea bah nk altarar cea ebaga eet aye cok aie a IO SON Seon e ues 80 160 
GR Tes eRe Baa ko IG Sale a iy Me NP Pt Lt Ma eh Ga eR i Ne ota 0 
a ae eee | SSS) SHPO set It BS a ONT LY Si SI by CN Ne 80 
Pa NP Ea tC A eas SNS ER BRD ee SB Sep Spa yo SOF SE we eae epee 80 
QU CREE HR Mn Het ACA As A er 80 LGUs eee en ees | ee ee 240 
BN a aE ate Sed RTI ca | eee ey eee nc aH oy eS LENE aU STs ey LOg EN i Le Cea 0 
5 Uo Spay pane Sele aS 21D RE AUR DALY Oe A OP ae Ok BPA Ve ee See ie 2 Ee a ie ae 320 
Ot, Maneater gies | HAE SeSeaC DOMAIN a sah SANE AN PVN EG ea a a i a RN 240 
iL SE Ri SE [ESS SC iC a nt lta is Teta 8 ch i ia ee Ni Lan 0 
1A BR ae | BPEL) Petes Pa PT CESS TY RU Sa a A 320 
FS SE OSES TE eI Ol eae TES ree eH es EI a ea LPN a a ee eee a ELSE Es AO aR Va a SC 0 
1 (G4) 2 ate a rae Bec Hie a9. Tea a Re Open ae N eM ane aa! Sol AN. Oak ML epee gear a gat 0 
TEE AE A eee R A Somes 5 Be eae Nes Sel Pepe Ane BO ern M glee eh dete emery anya me NG wie ee 0 
EP REE Sa Sr mela a pay ni Ks PMN LN epeta Sal Se ec a DU T) LL eat RR GOL dee Na NM EA Oe MI ae (aft 0 
LO LLANE LLL SPE ode cael ce oe ciel BS le ca df Yo Se BS aE A A PE a 0 
Q0seke ssi ds ceed Petiee: = SOU SO ec EEE a Eee Mee By 3 ie Ra ese eye Ses SA ae Pes Ce 0 
7 We am ie SESS Sits Sees eal lic eee a ried al eta eae aU PERC Bes Pali, AN TBSS RG UN he 80 
Cpa EE Uyb ayia ehh ene Wea ti eieette UR Bt It Re Seger aan oid ris aa gt | Pe Bg ea (i 0 
PRY. didi ese TSE est ep tS cls Eat se | RR a OR BR DAE ee | Lr ae AE i 0 
DEE SA ADO PS ee Ma OY A ORE REY V8 TS Dane a8 QO) area hy: oe ers ann es 80 
11 chain equals 66 feet; 40 chains equal one-half mile. 
60634244 
2 Picea engelmanni Engelm. 
