tok * 
LIFE HISTORY OF LODGEPOLE PINE IN ROCKY MOUNTAINS. 5 
“TABLE 1.—Climate within the lodgepole region—Continued. 
Ap- Killing frost. 
proxi- 
mate : 
Type of land or forest penieg en Spring. Fall. 
Station. at station—tim bered nich 
or open. whic snow- 
aver- fall 
ages Average | Latest | Average | Earliest. 
are latest. | known. | earliest. | known. 
| based 
Colorado: Years.| Inches. 
Gunnison. ..... Below timber line...-.. 21 46.5 | July 10 (1) Aug. 20 tY 
Moraine........ OLIOW, PiNGsck Mss 5552 23 96.1} June 17}, () Aug. 18 @ 
Marblescc: oc ee oe ee ee 4 157.4 | June 16} July 5] Aug. 26} Aug. 3 
SUSE A 2 be 00 (0 5 173.2 (2) (2) (2) (2) 
Georgetown. . ¥élloy pine (cut over). 11 94.0 (7) (2) (2) (2) 
Longs Peak. ... .| Lodgepole. See eae 18 119.5 | July 10 (@) Aug. 28 (1) 
Hed clive Sse he BORE eco ec oes 20 205. 4 2) (2) () ty 
Columbine. ....| Engelmann spruce.... 3 21105 (2) (2) (2) (2 
Frances. SE ek 6 27 010) (oe 8 183.5 | May 29] June 14] Sept. 10| Aug. 25 
Breckinridge. - SLO ee ees 24 193.9 | July 21 (1) Aug. 9 () 
Spruce Lodge... :| Engelmann spruce.... 5 270. 7 2 2 2 (2) 
Leadville....... Minera: £25 SF 15 134.9 | June 15 | June 21] Aug. 31| Aug. 3 
Garons=s co s2cek Above timber line..... 6 346.5 | July 18 Aug. 19 (4) 
Wyoming: 
Centennial. ....| Below timber line..... 10 134.8 | June 23 | July 9/{| Sept. 8} Aug. 25 
Woodrock3..... odsepoles. hse 2258 1 321.1 3 (3) 
Dome Lake. ..| Alpine................ 2 2 
Yellowstone Na- 
tional Park: 
Fort Pes ae UiSrerig) ee ae 9 
ston 
aaa Falls5... Wouclas ins =. a2. 2 3 
Riverside5.....| Lodgepole.-........... 4 
Sylvan Pass 5...]..... OF eacc = =. 4 
Snake River5...|..... Oe ae Rae ge ee 4 
Fairview 5...... DWouelas fir ss. se). 65 2 6 
Fountain 5...... Lodgepole............ 3 
Geyser Basin5..|..... CO Se 4 
INOLRIS DE. -o ce nob acess LO en bom alls 3 
Lake Yellow- |..... OBa ees Hest 5 
stone.5 : 
Grand Canyon5,.|..... OS. 88 Fase 2 1 SSH 5b este een ete oss | cree [ eee es oe 
Montana: 
HIDIGHR Ecos eat Below timber line..... 33 54.7 | May 7/| June 9 | Sept. 28| Sept. 5 
Livingston. ....|..... oe: SEN ale eR 14 40.4 | May 20} June 20 | Sept. 17 ty) 
BOZEMAN wee es eo GOS et se eee a 33 ile tal May. i28il sed Osee sp SCD lan dal eAUea. Lo 
Anaconda... AUPE TOYS ee ie eee a 11 40.6 | June 17| July 8| Sept. 6| Aug. 14 
Buttes: esa-2 <6 Below timber line...-. 18 55.2] June 5] June 26] Sept. 15 | Sept. 5 
Pipestone Pass.| Douglas fir............ 3 LOIS) | seeaaeecee | Fecrsres sich stall Recents eae eeecioerae tay 
Bowenr-c* fei 5.2 Below timber line..... 6 LOMIE |Eaeseee Haart neem (eae ayaa aS eee 
Fish Creek. -...| Lodgepole............ 3 182.5 
1 Midsummer. 
2 No data. 
3 Probably reaches freezing every month; no temperature record. 
4 Likely to get freezing temperature any month. 
5 Freezing temperatures every month in year. 
In southwestern Montana lodgepole occurs at elevations as low as 
4,500 feet on northern exposures, where there is the greatest atmos- 
pheric humidity and the least evaporation from the soil. South 
slopes at this elevation, if timbered at all, usually support only such 
Species aS juniper (Juniperus scopulorum) or Douglas fir (Pseu- 
dotsuga taxifolia), which require less soil moisture than lodgepole 
and are better constituted to resist transpiration. Lodgepole is found 
on southern exposures at about 6,000 feet, provided the gradient is 
less than 10 per cent. A steep south slope is generally too dry for 
the species. 
At the upper limit of its range lodgepole gives way to other and 
more tolerant trees. Increase in soil and atmospheric moisture en- 
courages such species as Engelmann spruce (Picea engelmanni) and 
