June 2 ,1923 
Effect of Manganese on Plant Growth 
787 
TablK III .—Analyses of composite samples of radish tops grown in Volusia and Dunkirk 
soils, with and witho2it the addition of nutrients, manganese sulphate, and calcium car¬ 
bonate (results calculated on moisture-free basis) 
Acid reaction of soil. 
Neutral reaction of soil. 
Element. 
Soil. 
No 
treat¬ 
ment. 
Miner¬ 
als 
Miner¬ 
als plus 
5 parts 
per 
million 
Mn. 
Miner¬ 
als plus 
lo parts 
per 
million 
Mn. 
CaCOa. 
CaCOa 
plus 
miner¬ 
als. 
CaCOa 
plus 
miner¬ 
als and 
5 parts 
per 
million 
Mn. 
CaCOa 
plus 
miner¬ 
als and 
10 parts 
per 
million 
Mn. 
CaCOa 
plus 
miner¬ 
als and 
50 parts 
per 
million 
Mn. 
Per 
Per 
Per 
Per 
Per 
Per 
Per 
Per 
Per 
cent. 
cent. 
cent. 
cent. 
cent. 
cent. 
cent. 
cent. 
cent. 
A cln 
/Volusia.,.. 
21. 89 
25. 60 
25 - 51 
24-45 
22. 06 
24. 96 
25-49 
26.00 
21. 71 
.. 
1 Dunkirk. . 
20. IS 
24. 83 
24. 58 
26. 76 
17-55 
19.06 
25. 08 
25-56 
25 - 45 
Fe. 
/Volusia.... 
.077 
•059 
• 050 
. 091 
.047 
•09s 
. 096 
.071 
. 08 
1 Dunkirk., 
•073 
•073 
•073 
•073 
• 074 
. 084 
•095 
. 091 
. II 
fVolusia.... 
. 046 
•03s 
• 058 
•94 
•054 
. 046 
. 070 
. 087 
I- 15 
iVXll .. • 
1 Dunkirk., 
. 024 
. 024 
• 056 
.67 
. 019 
. 021 
•034 
•059 
.84 
Ca 
/Volusia..., 
3-86 
3 - 59 
3- 12 
3 - 25 
3-01 
4 - 39 
4.44 
4 - 54 
2. 81 
... 
iDunkirk.. 
3.10 
3-32 
3 - 23 
3 - 95 
2. 72 
2. 85 
2. 91 
2. 96 
2. 98 
Ufo- 
/Volusia.... 
.46 
•45 
.41 
•38 
•43 
•38 
.40 
•44 
•38 
Alg . 
1 Dunkirk.. 
•43 
.40 
.42 
•43 
•45 
.42 
.41 
.42 
•34 
T3 
/Volusia.... 
• 25 
•25 
•78 
• 72 
• 24 
• 70 
• 70 
•65 
.68 
Jr . 
/Dunkirk.. 
. 27 
• 56 
• 55 
• 50 
• 25 
•59 
•58 
. 61 
. 60 
TT 
/Volusia.... 
4 - 56 
4 - 72 
6.67 
7-47 
6. 94 
4-33 
5 - 55 
6. 52 
6.35 
. 
/Dunkirk. . 
4-56 
4 - S6 
7.69 
7 - 99 
7-31 
3-52 
3- 16 
7-83 
7. 24 
V 
/Volusia.... 
6. 04 
6. 79 
6.58 
6. 71 
6. 15 
6. 48 
6. 52 
6- 45 
7.81 
. 
/Dunkirk. . 
5-56 
6. 77 
7. 22 
6.51 
3 - 19 
3-58 
5 -17 
5-04 
5 - S6 
An examination of the results shown in Table III reveals some points 
of interest. The plants which grew in the untreated soil contained less 
mineral matter than did those to which mineral nutrients were added. 
The addition of manganese to the soil in series No. i did not increase the 
mineral content of the plants receiving it, whereas it appears to have done 
so in the neutralized soil, except in pots 9 and 10, in which toxicity was 
produced. About as much mineral matter was taken up by the plants 
grown in the soil to which calcium carbonate was added as where it was 
omitted in the corresponding control pots of soil in series No. i. A 
little more calcium was taken up by the plants under neutral conditions 
of the Volusia soil than under acid conditions; however, a little less 
calcium was found in the plants that grew in the neutralized Dunkirk 
soil than in those theft grew in the acid soil. A larger percentage of 
potassium was found in the plants that grew in the acid Volusia and Dun¬ 
kirk soils to which manganese was added than in those plants that grew 
in the soil to which no manganese was added. There was an increase in 
the percentage of nitrogen in the plants to which manganese was added 
in the neutral Dunkirk soil, while the percentage of nitrogen was nearly 
constant in the other experiments. 
It appears, therefore, that in the soils dealt with in the foregoing 
series of experiments with radish plants, there has been a slight gain in 
each of the soils where manganese was added to the neutral soil in con¬ 
nection with mineral nutrients. Under acid conditions there has been a 
diminution in the yield of the plants receiving manganese when com¬ 
pared with the pots receiving mineral nutrients alone. All the soils 
have responded vigorously to an application of mineral nutrients when 
compared with no treatment. 
An inspection of the green and dry weights of the soybean plants in 
Table II indicates that a more favorable growth was obtained in the 
neutralized soil plus manganese than in the acid soil to which manganese 
