Sept. 1, 1925 
TTiermostasy of Growth of the Date Palm 
435 
Table II.— Interior temperatures of the date palm compared with air and soil 
temperatures of corresponding hours, March 1 to 6 
Time 
Air 
Soil at 
2 feet 
Bud 
zone 
(by 
ther¬ 
mom¬ 
eter 1) 
Trunk 
(by 
ther¬ 
mom¬ 
eter 2) 
Time 
Air 
Soil at 
2 feet 
Bud 
zone 
(by 
ther¬ 
mom¬ 
eter 1) 
Trunk 
(by 
ther¬ 
mom¬ 
eter 2) 
Mar. 1: 
°F. 
°F. 
°F. 
°F. 
Mar 4—Contd. 
°F. 
°F. 
°F. 
°F. 
6.20 a. m_ 
a 46.40 
62.60 
b 63.05 
6.30 p. m_ 
67.55 
68.00 
65.30 
8.00 a. m_ 
63.95 
_____ 
63.14 
63.05 
7.30 p. m_ 
66.65 
68.90 
65.30 
10.00 a. m_ 
71.60 
_ _ 
6140 
63.05 
9.00 p. m_ 
64.85 
_ 
68.90 
66.20 
12.00 a. m_ 
73.85 
__ 
62.60 
62.60 
10.00 p. m.__ 
63.50 
_ 
68.90 
66.20 
1.00 p. m.__ 
78.85 
60.5 
62.60 
62.15 
Mar. 5: 
3.30 p. m._. 
76.55 
62.15 
62.15 
6.15 a. m_ 
56.75 
___ 
70.70 
67.10 
4.30 p. m„ _ 
74.30 
62.60 
62.15 
7.00 a. m_ 
59.45 
71.60 
67.10 
7.0ft p. m 
58.10 
63.95 
60.80 
7.45 a. m_ 
68.90 
72.50 
68.00 
Mar. 2: 
8.20 a. m_ 
72.05 
72.50 
68.00 
10.00 a. m_ 
74.30 
65.80 
63.50 
9.00 a. m_ 
72.50 
72.95 
67.55 
12.00 a. m_ 
78.80 
63.50 
62.60 
10.00 a. m_ 
74.30 
72.95 
67.28 
2.00 p. m.__ 
79.70 
63.50 
62.15 
10.30 a. m_ 
77.45 
72.50 
67.10 
3.30 p. m_ 
78.80 
63.05 
61.70 
11.00 a. m_ 
77.90 
71.15 
67.28 
7.00 p. m___ 
55.40 
61.5 
64.40 
63.05 
12.00 a. m_ 
79.25 
70.34 
67.10 
9.00 p. m_ 
57.80 
65. 75 
63.95 
1.00 p. m_ 
77.90 
62.5 
69.08 
66.74 
10.00 p. m_ 
54.50 
66.20 
63.50 
2.15 p. m___ 
79.70 
_ 
68.54 
66.20 
Mar. 3: 
3.00 p. m_ 
76.55 
_ 
68.45 
65.30 
6.15 a. m_ 
47.75 
_ 
67.10 
65.80 
4.00 p. m_ 
74.75 
69. 36 
65.75 
7.15 a. m_ 
57.95 
_ 
67.55 
65.30 
5.15 p. m_ 
71.60 
______ 
68.36 
66.20 
11.00 a. m_ 
78.80 
67.55 
64.40 
6.30 p. m___ 
67.55 
_ 
69.80 
66.20 
1.00 p. m___ 
79.70 
62.0 
65.30 
63.50 
7.30 p. m_ 
65.30 
_ 
70.70 
67.10 
2.00 p. m_ 
79.88 
__ 
63.50 
63.14 
9.00 p. m.__ 
65.30 
_ 
71.60 
68.00 
4.15 p. m_ 
77.90 
_ 
63.50 
63. §5 
Mar. 6: 
6.30 p. m___ 
61.25 
66.20 
63.50 
6.10 a. m_ 
54.95 
71.78 
69.80 
7.30 p. m___ 
56.75 
66.20 
64.40 
7.45 a. m_ 
61.25 
71.37 
68.90 
9.0ft p. m 
67.55 
67.55 
64.40 
8.30 a. m_ 
62.78 
72.50 
68.90 
Mar 4; 
9.40 a. m_ 
67.55 
72.50 
68.90 
6.10 a. m_ 
45.95 
71.60 
67.10 
10.30 a. m—- 
66.65 
78.68 
68.90 
7.45 a. m __ 
58.55 
70.70 
67.10 
11.00 a. m_ 
69.80 
73.40 
68.45 
8.45 a. m _ 
61.70 
72.05 
67.10 
12.00 a m_ 
69.98 
72.95 
68.00 
10.00 a. m _ 
66.65 
72.50 
67.10 
1.00 p. m_ 
69.44 
72.05 
67.55 
11.00 a. m_ 
71.15 
72.50 
66.65 
2.00 p. m.__ 
70.70 
62.5 
70.70 
67.55 
12.00 a. m_ 
75.20 
_ _ 
71.15 
66.20 
3.00 p. m___ 
69.35 
_ 
72.05 
67.10 
1.00 p. m___ 
77.00 
_ _ 
69.35 
65.75 
4.00 p. m_ 
67.55 
_ _ 
69.98 
67.10 
2.00 p. m___ 
77.90 
62.5 
68.00 
65.30 
5.00 p. m___ 
65.48 
_ 
69.89 
67.10 
3.00 p. m_ 
78.08 
_______ 
67.28 
65.30 
6.20 p. m.__ 
63.05 
_ 
69.80 
67.10 
4.00 p. m___ 
77.90 
_ _ 
67.10 
65.30 
8.00 p. m_ 
60.80 
71.60 
67.10 
5.00 p. m___ 
72.05 
67.10 
65.30 
9.00 p. m___ 
59.90 
71.60 
67.10 
a Figures in bold-face indicate lowest temperatures for the day. 
b Figures in italic indicate highest temperatures for the day. 
Table III shows similar records from March 26 to April 1, inclusive, 
during which time the minimum air temperatures passed above 60° 
while the maxima for March 30 and 31 were above 95°. Table IV 
and Figure 6 show the records of both upper and lower thermometers 
in the Zaheedy tree for the period from April 21 to 27, inclusive, where 
the holding down of the temperature of the lower trunk interior is 
most pronounced. 
