Use of liquid anhydrous ammonia as a fertilizer

Abstract

(1) At rates of 40, 80 units N/ac. in field, experiments and at rates of 45 , 90, 180 , 720, and 1440 lb. N/ac. in the greenhouse experiment, sulphate of ammonia proved a better source of N for grass D.M. yield than anhydrous ammonia or ammonia solution.

(2) There were toxic effects on plant resulting from NH₃, and NH₄, OH. On the field effects were seen on grass along the injection lines; in the greenhouse experiment toxicity symptoms were pronounced on grass receiving over 180 lb. N/ac.

(3) At 1440 lb. N/ac., some plants failed to emerge and were killed by NH₃ at or before the seedling stage. In some pots, 95 plants out of 100 failed to emerge and were killed.

(4) Anhydrous ammonia applied to grassland as well as ammonia solution applied to ryegrass in pots, underwent a rapid nitrification as compared with (NH₄)₂ SO₄.

(5) Due to the retarded effect of NH₃ on plants, the greater release of NO₃ did not benefit plants. The slower release of NO₃, in the (NH₄)₂SO₄, treatments seemed to be in pace with plant requirement of N.

(6) Mechanical damage to grass turf caused by anhydrous ammonia injection was one of the reasons behind the lower yield obtained from NH₃ as compared with (NH₄)₂SO₄.

(7) In some cases where the soil was stony, NH₃ escaped into the atmosphere and caused a substantial loss of fertilizer N. The grass leaves were scorched as a result of coming into contact with the escaped NH₃.

(8) There was greater loss by leaching NO₃ from, the NH₄ OH treatments as compared with (NH₄) SO₄ . The difference between the two sources increased with increasing rate of N.

(9) There was a greater loss of applied N from the NH₄OH, as compared with (NH₄)₂SO₄ treatments. Soils seemed to fix more N from NH₄OH than from (NH₄)₂SO₄. Some NH₃ was lost by volatilization from OH treatments but this loss was negligible with (NH₄)₂SO₄.