36 o 
Journal of Agricultural Research 
Vol. V, No. 9 
old sample, as all the leaves and straw were partially or completely 
withered at this period. The 18- to 48-day-old samples had no withered 
leaves, so that these analyses represent the whole plant aboveground. 
Table II .—Ash analyses of vegetative parts of the rice plant at various periods 
If 
|8 
Percentages 
in dry mat¬ 
ter of— 
Percentages in carbon-free ash of- 
Part of plant. 
Age of plant. 
O g 
V QJ 
II 
I 
ft 
Carbon-free 
ash. 
Nitrogen 
(N). 
Silica (Si02). 
A 
l 
i 
Magnesia 
(MgO). 
A 
i 
ft 
A 
23 
ft 
1 
s-' 
Phosphoric 
acid (P2O5). 
S u 1 p huric 
add (SO3). 
a 
53 
43 
0 
Green leaves and 
stalks. 
Do. 
Days. 
18 
26 
18.7 
SO. 2 
17 - 75 
14.97 
4-02 
56.88 
56-34 
2.21 
2.40 
3.69 
4.24 
0.75 
• 35 
22.91 
17.28 
I. 55 
9 - 76 
7-94 
6.65 
9.24 
5-81 
4-47 
Do. 
48 
14 - 6 
22. 21 
1.89 
62. 56 
I- 73 
3 * 11 
. 21 
14.66 
9-57 
4.00 
4.41 
4. xo 
Do. 
73 
20.1 
16. 95 
1-93 
64.82 
i* 73 
3.04 
.18 
16.88 
4-55 
3 - 39 
3 - 89 
5-37 
Do. 
103 
21. 5 
13- 28 
1.01 
67. 71 
2.12 
3* 26 
. XI 
9*54 
10.31 
4.96 
3- 61 
4-52 
Withered leaves and 
stalks. 
123 
28. 7 
20. 23 
.62 
74.00 
1.83 
2. 27 
■ 32 
12.65 
4*85 
1.80 
2. 52 
3. 26 
Withered leaves. 
73 
37*4 
30* 12 
1.16 
83-51 
3 * I? 
3.08 
•97 
6.44 
i- 3 i 
1-33 
1. 73 
1.69 
Do. 
103 
61. 0 
27. 60 
.41 
85.10 
3-00 
2.84 
.72 
2. 74 
2 - 33 
.67 
1. 20 
.80 
Panicles immature.. 
103 
48.5 
8.86 
1.18 
78.15 
I. 17 
2.68 
.07 
6.80 
3> 20 
6.91 
3 - 72 
.68 
Panicles with ripe 
seed. 
123 
72.8 
4. 82 
1. 26 
68.93 
I. 31 
4.91 
.06 
9 - 74 
x. 04 
14. 67 
5-6o 
The percentage of iron in the ash of the green straw and leaves decreased 
regularly and rapidly with the maturity of the plant, the greatest decrease 
being from the 18-day-old to the 26-day-old sample. 1 The withered 
leaves had a relatively high percentage of iron. This may be due to the 
other samples, consisting of both leaves and stalks, or to the fact that 
the withered leaves of the 73- and 103-day-old sample were the leaves that 
appeared first—i. e,, those forming a large part of the first samples. 
The varying percentages of iron in the ash of the green straw and 
withered leaves agree with some of the results obtained by Arendt 2 with 
oats. He found that the lower leaves of wheat, which must have been 
withered at the later periods of analysis, contained increasing percentages 
of iron, which were much greater than the percentages of iron in the ash of 
the upper leaves. 
The lower percentages of potash, phosphoric acid, sulphur, chlorin, and 
nitrogen in the ash of the withered leaves may be due to translocation of 
these elements preceding death of the leaves or to loss by leaching after 
death of the tissue. 
In Table III is given the ash composition of the roots and of the whole 
plant aboveground. The roots for analysis were washed with great care, 
1 These results are in accord with many analyses of green rice straw made previously. Four samples of 
rice straw from plants grown in four different soils for 25 days contained from 2.76 to 1.98 per cent of iron 
(FeaCh) in the ash, while samples from a crop grown 84 days had 0.31 to o.r8 per cent, and samples from a 
129-day-old crop had but 0.12 to 0.10 per cent of Fes03 in the ash. (Gile, P. L., and Ageton, C. N. The 
effect of strongly calcareous soils on the growth and ash composition of certain plants. Porto Rico Agr. 
Exp. Sta. Bui. 16, p. 31, 1914-) 
2 Arendt, R. F, E., Untersuchungen iiber einige Vorgange bei der Vegetation der Haferpfianze. In 
Landw. Vers. Stat., Bd. 1, p. 31-36. 1859. 
