784 
Journal of Agricultural Research 
Vol. XXIV, No. 9 
KXPJ^RIMENTS WITH VOI^USIA SII,T I,OAM SOU, 
Volusia silt loam soil has a brownish-gray color, is low in organic 
matter, and contains considerable clay. It requires about 2,000 pounds 
of calcium carbonate per acre foot to neutralize its acidity. 
About 500 pounds of this soil were obtained in a pasture field on 
Turkey Hill, Tompkins County, N. Y. The soil was well mixed and 
allowed to air-dry. Representative samples were taken for determina¬ 
tion of the total and water-soluble manganese. 
The total manganese content was determined by the potassium 
bisulphate fusion and the colorimetric periodate method. The amount 
of manganese found by this method was 0.08 per cent, or 800 parts per 
million of the air-dry soil. The amount of manganese dissolved by 
digestion with distilled water was 6.25 parts per million of the air-dry 
soil. 
For pot experiments, 4,000 gm. portions of the air-dry soil were 
weighed into clean i-gallon earthenware jars without drainage. Two 
series of 12 jars each were prepared, one with and the other without 
calcium carbonate, as shown in Table I, each treatment being made in 
duplicate. The mineral nutrients consisted of 10 gm. calcium nitrate, 
10 gm. dipotassium phosphate, and 5 gm. magnesium sulphate per jar. 
TabliS I .—Pot treatments in Series I and II 
Pot No. 
Treatment, Series I. 
Treatment, Series II. 
I and la... 
No treatment. 
20 gm. CaCOa. 
2 and 2a... 
Mineral nutrients only. 
Mineral nutrients and 20 gm. CaCOs. 
3 and 3a... 
Mineral nutrients and 5 parts 
per million Mn. 
Mineral nutrients, 20 gm. CaCOs and 
5 parts per million Mn. 
4 and 4a... 
Mineral nutrients and 10 parts 
per million Mn. 
Mineral nutrients, 20 gm. CaCOs and 
10 parts per million Mn. 
5 and 5a.., 
Mineral nutrients and 50 parts 
per million Mn. 
Mineral nutrients, 20 gm. CaCOs and 
50 parts per million Mn. 
6 and 6a... 
Mineral nutrients and 100 parts 
per million Mn. 
Mineral nutrients, 20 gm. CaCOa and 
100 parts per million Mn. 
Purple-top radish seeds were sown in each pot and the moisture con¬ 
tent of the soil in each pot was brought to one-half saturation, by weight, 
with distilled water. After the seedlings were up they were thinned to 
10 plants in each pot and the moisture content kept at approximately 
one-half saturation with distilled water during the time the plants were 
making their growth. 
Immediately after the crop of radishes was harvested soybeans were 
planted in each of the pots without further treatment of the soil. After the 
beans had reached the proper size they were thinned to 6 plants in each 
pot and allowed to grow until they were approaching maturity, the 
moisture content being meanwhile kept up to about one-half saturation 
' with distilled water. 
Plate I, A, represents five pots from series No. i. Pot No. i is one of 
the control pots and represents the productivity of the soil without 
treatment. Pot No. 2 shows the effect of the addition of appropriate 
amounts of phosphorus, potassium, calcium, magnesium, nitrogen and 
sulphur to the soil. This is one of the pots that received mineral nutrients 
