6 
Journal of Agricultural Research 
Vol. V, No. i 
Table III .—Quantity of dry matter {in grams) produced by wheat and sugar-beet plants 
raised in soil containing alkali salts in various concentrations 
Dry matter. 
Concentration 
of salts (p. p. m. 
of dry soil). 
Wheat. 
Sodium 
chlorid. 
Sodium Sodium 
carbonate, sulphate. 
Magne¬ 
sium 
sulphate. 
Sodium 
chlorid. 
None. 
ioo. 
500 
1,000 
2,000 
o. 131 
• 095 
.185 
. <ko 
.034 
o. 131 
. 142 
. 082 
. no 
. 117 
O. 131 
. IOO 
. 070 
. 103 
. 121 
o. 131 
. 118 
. 117 
. 147 
. 114 
O. 020 
. Ol6 
.032 
•034 
. 017 
Sugar beets. ' 
Sodium 
carbonate. 
Sodium 
sulphate. 
O. 020 
. IOI 
. 007 
• 01.5 
.023 
O. 020 
. 019 
. 012 
. 020 
.005 
Magne¬ 
sium 
sulphate. 
O. 020 
.013 
.017 
. 018 
. 027 
3»°o° 
4,000 
$,000 
6,000, 
7,000 
. 098 
. 080 
. 119 
. 090 
•039 
•075 
. 078 
. 080 
.088 
. 052 
. 114 
. 108 
•073 
. 144 
. 060 
.005 
023 
026 
026 
013 
002 
•033 
*039 
. 048 
•035 
•035 
. 029 
.031 
.013 
.023 
•037 
8,000 
9,000 
10,000 
.034 
. 010 
. 036 
. 048 
. 029 
. 129 
.094 
. 126 
. 025 
•015 
■015 
.038 
•033 
•035 
While the data in the tables are somewhat irregular on account of the 
comparatively small number of plants used, a few facts come out rather 
clearly. Probably the most conspicuous of these is the relatively high 
toxicity of sodium chlorid (NaCl) in Greenville soil when compared with 
other salts. 
Two thousand p. p. m., or 0.2 per cent, marked the limit of growth 
for wheat, while three thousand p. p. m. was the limit for sugar beets. 
There was germination and growth with considerably more sodium car¬ 
bonate (Na 2 C 0 3 ) than sodium chlorid, although the carbonate dissolved 
the organic matter from the soil, producing a very bad physical condition. 
Magnesium sulphate (MgS 0 4 ) was only slightly toxic at a concentration 
of 1 per cent of the soil, while sodium sulphate (Na 2 S 0 4 ) was more toxic, 
but produced fair crops where 1 per cent was present. The percentage 
of germination, the height of plants, and the dry weight all correspond in 
showing where the growth began to be retarded by salt. 
In order to determine the effect of the percentage of soil moisture on 
the toxicity of alkali, tests were made with soils having 12.5, 15, 17.5, 
20, 22.5, 25, 27.5, and 30 per cent of water on the dry basis. At the 
one extreme the soil was about as dry as plants would grow in, while at 
the other it was completely saturated. The soil used w r as Greenville 
loam, and the seed planted was New Zealand wheat. The methods 
were the same as those already described, with 10 seeds in each glass. 
The seeds were planted on August 16 and the plants harvested on 
September 27. The results are shown in Table IV. 
