632 
Journal of Agricultural Research 
Vol. V, No. 14 
It will be seen from these figures that the integrated transpiration for 
wheat and oats slightly exceeds the integrated radiation and that the 
reverse is true for rye, sorghum, amaranthus, and alfalfa. The transpi¬ 
ration curves for sorghum, amaranthus, and alfalfa lie almost wholly 
within the radiation curve. The ratio of the transpiration area to the 
radiation area is also low in the case of spring rye, owing to the com¬ 
paratively low rate of transpiration during the morning hours. 
Fig. i 6.—Comparison of the form of transpiration graphs with the graphs representing the total radiation 
and the vertical component of the radiation. 
TablF XXXVI .—A comparison of radiation and transpiration based on the area in¬ 
closed by the graphs in figure IJ 
Plant. 
* 
Area bounded 
by— 
Ratio 
of tran¬ 
spira¬ 
tion to 
radia¬ 
tion 
area. 
Transpiration. 
Radia¬ 
tion 
graph. 
Tran¬ 
spira¬ 
tion 
graph. 
Area 
for day¬ 
light 
hours. 
Day¬ 
light. 
Night. 
A. M. 
P. M. 
11 a. m. 
to 3 
p. m. 
Per 
Per 
Per 
Per 
Per 
cent . 
cent . 
cent. 
cent . 
cent. 
Wheat. 
302 
310 
1.03 
298 
96 
4 
44 
56 
37 
Oats. 
289 
303 
1.05 
286 
94 
6 
44 
56 
39 
Rye. 
357 
306 
.86 
290 
95 
5 
38 
62 
36 
Sorghum. 
283 
253 
.89 
240 
95 
5 
43 
57 
45 
Amaranthus... 
346 
284 
.82 
275 
97 
3 
42 
58 
40 
Alfalfa. 
3 i 5 
271 
.86 
264 
97 
3 
44 
56 
43 
