Elemental Composition of the Corn Plant 
847 
Mar. 15, 1924 
pulverized for chemical analysis. In the preparation of material the 
husks were placed with the leaves and the tassel with the stem. The 
cobs of the five plants were ground together and the analysis made of 
this mixture, so that the variation in the composition of these organs 
was not determined. 
TABrE II .—General description of the five corn plants at the time of harvesting 
* ! 
i 
! 
Plant No. 
Total 
green 
weight. 
Dry weight of— 
Per¬ 
centage 
of 
mois¬ 
ture 
in 
plant. 
Height 
of 
plant. 
Length 
of 
ear. 
Num¬ 
ber of 
leaves. 
Entire | 
plant, j 
exclud- j 
ingthe j 
roots. ! 
i 
Stems 
and 
tassel. 
j 
Leaves® i 
and | 
husks. | 
Grain. 
Cob. 
Grams. 
Grams. 
Grams. 
j 
Grams. 
Grams. 
Grams. 
Inches. 
Inches. 
I. 
2, 540 
776.3 
154-3 
209.4 
320. O 
92. 6 
69.4 
102 
12 
15 
2. 
2,923 
791.1 
191. 2 
252.4 
272. 2 
75-3 
72.9 
96 
13 
16 
3 . 
2,277 
659- 5 
l6l. O 
195.8 
232. O 
70. 7 
71. O 
IOI 
12 
14 
4 . 
2,716 
745- 8 
233-0 
235 - 5 
212. O 
65- 3 
7 2 * 5 
108 
II 
14 
5* .. 
3 ,o 95 
899-3 
263.5 
279.7 
268.8 
87-3 
7°-9 
120 
13 
17 
Average. 
2,710 
774-4 
200. 6 
234.6 
26l. O 
78. 2 
7 i -4 
I°5 
12 
15 
a Including sheaths. 
ROOTS 
It is practically impossible to collect all of the roots of a com plant 
grown under crop conditions in the field since one is unable to dis¬ 
tinguish or separate the finer roots that are interwoven with those 
of the adjacent plants. In order to obtain the entire root system, 
plants of the same variety of corn as that grown in the field were grown 
singly in soil in large galvanized iron cans. These cans contained 
a sufficient volume of soil to grow plants to maturity that in appearance 
were the equal in every regard of those growing under the conditions 
of the surrounding field. The methods used in growing plants in such 
containers have been previously described by Miller ( 8 , 9) 2 and will not 
be discussed here. When the plants in the cans had reached maturity, 
the aerial parts were harvested and discarded and the roots collected 
in the following manner: The soil contained in the can was emptied 
*upon a cleared space and the larger roots removed by careful sorting. 
The soil with the smaller roots was then placed in vessels and covered 
with a large excess of water which was stirred vigorously until the soil 
had disintegrated into fine particles. As soon as the stirring ceased, 
the soil settled to the bottom of the vessels while the remnants of roots 
floated to the surface and were removed by skimming with a fine sieve. 
The process was repeated several times until all the roots had been 
separated from the soil. The roots thus obtained were washed carefully 
until, in so far as could be seen, they were free from all soil particles, 
dried in a hot-air oven at 105° C. for 24 hours, and stored in sealed jars 
until chemical analyses could be made. A representative root system 
of one of the five obtained after this manner is shown in Plate 1, C. 
* Reference is made by number (italic) to “Literature cited," p. 859* 
