1905] WHITFORD—FORESTS OF FLATHEAD VALLEY Niaee 
ature has anything to do with the difference in the character of the 
vegetation, it must be the temperature of the non-growing rather 
than of the growing season. 
It is too often assumed that during the non-growing season physio- 
logical processes of plants are inactive.? Of course, this is true of 
growth; indeed, growth is checked and ceases rather early in the 
season; but photosynthesis is known to occur during the winter 
Experiments by MryAkE'° show that this process is active 
at temperatures in the neighborheod of o° C. Among the evergreen 
leaves experimented upon were species of pine and spruce. One 
of MIyAKe’s conclusions is that starch is formed in winter, though 
Peer Lee EEL 
Pere eet] 26 a a 
Chott : ~ 3 
HEE SS SOC 
rc? EE “SRC 
2 ‘aa WT 
x ia 
aa Oe 
+ ++ 
10° 
HH COPS 
Seen aes), Sees 
0 a aaean~S 
Sree S 
Sanu LY SSC 
oe? CLEEerrr v Eae@ 
= a8 
RCT rth CoC 
2 7 tt t 3 
SAE 2 8 a 7 Corr 
csu0 Chey 
anes rhe 
—I0 Lice 
Ja F Mr Ap My je ji Ag = a. ee 
), Kalispell ( 
Fic at seeps temperature wn Seattle ( ), 
eaten Falls ( +), and Marquette ( —-====— ; the figures are temperature 
Centigrade; winter r temperature for nai mans high, for Marquette low, 
for Kalispell and Columbia Falls intermediate; summer temperature for all stations 
nearly the sam 
in small amounts, and its translocation occurs in the same season. 
His work was conducted at Tokyo, Japan, where the mean tem- 
perature of the three winter months is as follows: December, 5.1° C.; 
January, 2.7°C.; and February, 3.5° C. If trees can do photosyn- 
9 Meastan « ays that ‘‘in computing the sum of the positive or effective tempera- 
t a minimum of 6° C. has been assumed as marking the inception of the period 
of physiological activity in plants and of reproductive activity in Sa Miaheem, 
‘od ife zones and crop zones of the United States. U. S. Dept. Agric., Div. 
Biol. foes » Bull. ro: 4, note 2. 1808. 
Migs » K., On the starch of evergreen leaves and its relation to photosyn- 
thesis during a aiaaee: Bort. GAZETTE 33: 321-340. 1902. 
