FERTILIZING EXPERIMENTS WITH ANHYDROUS AMMONIA AT KOTKANIEMI

Abstract. On spring cereals and in fertilization in connection with the sowing of winter cereals the effectiveness of ammonia is comparable to that of calcium ammonium nitrate. In tests that were arranged at Rikkihappo Oy’s experimental farm Kotkaniemi it was established that anhydrous ammonia given in connection with spring cereal fertilization and autumn cereal earthing is equal to CAN in effect. 16 tests were carried out during a period of five years using placement fertilization the soil being silty clay in most cases. Differences did not occur in the grain yield, the 1000-grain number hl-weight or in the protein content of the grain crop. Urea proved to be less effective than the two other fertilizers.

can seldom be carried out properly.Nor is ammonia suitable for winter cereals in spring because it may uproot the plants in connection with the injection (van Burg et al. 1967).
Autumn injection is often too risky in Western Europe because of larger N-losses in mild and wet winters.Under certain conditions, however, autumn application might be suc- cessful (van Burg 1969).
In Finland anhydrous ammonia has been used only in experiments.Fertilizing ex- periments with ammonia have been carried out on the Kotkaniemi experimental farm at Vihti, the total number of experiments being sixteen during five years, 1966-70.The experiments have been made with spring and winter cereals.The experiments have been carried out with a Danish Marsk Stig apparatus which is easy to use and has a satisfactory injection accuracy.When the experiments were started the tank of the machine was replaced by gas bottles filled with ammonia in order to perform fertilization to a depth of 15 cm and make the ammonia fix perfectly into the soil.The working of the cultivator at the back of the machine is weak.
The precipitations and the mean temperatures of the test years (1965 -70) are given in Table 1.
Table 1.Climatic conditions at Vihti during the growing seasons 1965-70.(2 e x p e r i m e n t s ) (3 e x p e r i m e n t s )

Results
The results of the experiments are given in Tables 2-6.Used in autumn on winter wheat and rye ammonia proved (Table 2) to have a fertilizing effectiveness as good as  % that of calcium ammonium nitrate or even better, similarly on spring wheat and barley (Table 3).No differences can be seen in the hl-weights, in the 1 000 grain weights or in  4 and 5) on wheat, ammonia gave a 5 % and urea an 11 % lower yield than calcium ammonium nitrate.On barley ammonia gave an 11 % higher yield than calcium ammonium nitrate and urea a 15 % weaker yield than calcium ammonium nitrate.Especially in 1966 urea gave a poor yield.As to the components, such as falling number and protein content, having an effect on the crop quality there are no differences between different fertilizers, nor are there any differences in the changes of the soil pH.
The crop yields obtained with pea-oats shown in Table 6 are the same in the cases of ammonia and compound fertilizer and additional nitrogen given in spring.Table 6.Experiment with anhydrous ammonia on pea-oats mixture.Soil type clayey sand and silt.Soil analysis in 1967; pH 6.4, Ca 1 600, P 24.0 and K 470 mg/1.In spring 500 kg compound fertilizer (15-25 10) by drilling -|-200 kg/ha calcium nitrate by broadcasting on shoots.Test made with pea- oats mixture (Pendek  Kalle).Size of test plot 5 X 30 m. 4 replicates.

Treatment
Grain yield Lodging kg/ha rel.

Only spring fertilization
Test plot was so heavily fertilized in spring (500 kg/ha compound fertilizer (15-20-15) -f-200 kg/ha calcium nitrate) that ammonia used in autumn did not have an increasing effect on the crop.

F
the crude protein.When comparing ammonia, calcium ammonium nitrate and urea T