320 



FORESTRY INVESTIGATIONS U S. DEPARTMENT OF AGRICULTURE. 



Soil iemperaUoes — Continued. 



+ 1 































s»— ""*'«. 



.-T^!*S 



— 



."^Jv 



















,-tfss; 

 .»•» 



-1° 









3> 













S / 



* 

 * 

 * 



- 2>° 











v — 



\ 

 \ 











/ , 

 / / 



/ / 



* 

 * 

 * 





-3° 











... „„. 









/S/ 



/ 





-4° 











\ \ 



\ 







/ J 



/ / 



* 

 t 







-5° 











\\ 







- r "/n" 









-B° 













V 



**»■»••*• 



• / 











-7° 



























-8° 











... . .. 



















WINTER. 



SPRING 



SUMMER 



AUTUMN 



Fig 41 — Difleienco ot soil temperature ( F— 0), all stations— Gorman obsen itioiiq 



1 



AT SIX INCHES- AT FOUR FEET 

































^-— "~ 



— — — 



— ^ 



\ 

















^ — 



- 1° 





. 







»». 













— y*. 



m' 



-2° 







" 



N 













/ 







-3° 











"XV 



X- ii ii- 









s 

 / 



/. - 



/ 



r 





-4° 











* 



V 















- 1° 













\" 



****'■ «^«. ■** 



.— •-"" 



y 







sr.rrr,r.: 







^, 



« 























- \° 









N "" 



V 













/ 

 / 



,/. 



r »»"* 



,-*""" 



-2° 





• 





> 



I 













y* 





-3° 











sV - 

















-4° 











w 



, 





/ 











- 5° 













\ 















+ r° 



■*c.C.-.. .." 



"""-'ILL 









i, i 



«--.-!'' 



's 

















"V 



















s" 





£ 



D 

 CO 



*- 



< 







— I 







» , n 



\ 













/ 



/ 



^«.- ■ 



-2° 







1 





; 











/ 



X 





— 3 







: 



-5 



v ■ 









/ 



f / 







-4° 





'" ■■" 





\ 



V 



> 

 i 







A 



' 







-5° 













- i 







tf 









-6° 











\\ 







*m 











*— 7° 













VV""- 

 \ - 



-.,—.-*' 



y 











™j_o 















;" , .. l > , 

















WINTER 



SPRING. 



SUMMER 



AUTUMN. 





Fig. 46 —Differences of soil temperature (woods and open fields) Comparison of ele 



^ ationa above w a le\ el ( TT— 0) 



j, t surface ■ At 6 inches lelow surface At 4 feet Mow surface. 



Fig. 47 — Difiercnces oi temperature for joung trees, Lmtzel Station, woods and open fields (W— O) 



