2 
Journal of Agricultural Research 
Vol. XXVI, No. x 
from these investigations that for certain crops nitrites may be bene¬ 
ficial in small amounts, but harmful in larger quantities: also, that nitrites 
affect germination and retard early growth of young plants. Further 
investigations must be made, however, before definite conclusions 
can be drawn relative to the effects of nitrites on plant growth. 
In view of the results obtained by previous investigators, the rapid 
oxidation in the soil of nitrites to nitrates seems desirable, and necessary 
for the best development of the plant. Accordingly, the work reported 
herein was undertaken in order to learn whether nitrites when used 
in quantities comparable to those used as a fertilizer changed rapidly 
to nitrates in Oregon soils. 
EXPERIMENTAL PROCEDURE 
The different soil types used in the experiments were prepared by 
passing the air-dried soil through a io-mesh sieve with as little grinding 
as possible. Four hundred gm. of soil on the dry basis were then weighed 
out and enough distilled water added to obtain a slightly moist, crumbly 
condition. The soil was transferred to suitable pots and allowed to 
stand 24 hours. The various pots containing each soil type then received 
treatment as indicated in the tables. Throughout the experiment, 
whenever sodium nitrite was applied 0.4 gm. of the salt was added to 
each pot of 400 gm. of soil. Although the chemically pure salt was used, 
0.4 gm. of sodium nitrite contained 0.012 gm. of nitrate calculated as 
N 0 3 . In order to facilitate thorough mixing with the soil, the sodium 
nitrite was first dissolved in 25 cc. of water. Finally, a fresh soil infusion 
was added, together with enough water to obtain optimum moisture 
content, as judged by the physical appearance of each type. The initial 
moisture content was maintained throughout the incubation period by 
the addition of water, except as otherwise stated, and the soils were kept 
at a temperature ranging between 18 0 and 24 0 C. Immediately after 
each pot was prepared, 10-gm. portions of the soil on a dry basis were 
weighed out for nitrite and nitrate determinations. Water extraction 
was made by shaking in a mechanical shaker for about an hour, after the 
addition of a small amount of aluminum hydrate for clarification of the 
soil solution. The bottles were then centrifuged to settle suspended 
particles and nitrite and nitrate nitrogen were determined in the clear 
solutions. Determinations were subsequently repeated at the intervals 
indicated in the tables. 
OBSERVATIONS AND RESULTS 
In choosing the soil types, attention was given more to the reaction 
of the soil than to its physical characteristics. Consequently, acid soils, 
of varying degrees of acidity as measured by the Veitch (7) method, 
neutral soils, and alkaline soils were selected. For convenience the 
soils were divided into two series. The first series as reported in Table 
I are acid soils, while the second series, in Table II, are neutral and 
alkaline soils. A brief description of the soils used in the first series is as 
follows: 
Soil No. 11076 is classified as a clay loam having a lime requirement 
of 1.5 tons of calcium carbonate to the acre of 2,000,000 pounds. 
Soil No. 11077 is a gravelly loam having a lime requirement of slightly 
less than one ton to the acre. 
