HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Jacobson, J. S. Articles by Claypool, P. L. Search for Related Content PubMed Articles by Jacobson, J. S. Articles by Claypool, P. L. Agricola Articles by Jacobson, J. S. Articles by Claypool, P. L.

Distribution of Applied Anhydrous Ammonia in Soils and Germination Hazard to Winter Wheat¹

ABSTRACT

Current changes in residue management systems for winter wheat (Triticum aestivum L.) include anhydrous NH₃ injection combined with herbicide application, planting, and other field operations. The feasibility of NH₃ application during planting is dependent upon potential NH₃ toxicity to germinating seeds. A laboratory experiment was conducted to study anhydrous NH₃ movement in soils by injecting 124 and 180 mg N as NH₃ into a Hollister clay (fine, mixed, thermic Pachic Paleustolls), Grant silt loam (fine-silty, mixed, thermic Udic Argiustolls), and Norge clay loam (fine-silty, mixed, thermic Udic Paleustolls) at 0.124 and 0.181 water (kg kg^–1) contents. Soil samples were taken 1, 7, and 14 d after N application. Soil NH⁺₄-N and calculated NH₃(aq) concentrations following NH₃ injection generated a normal distribution curve with N concentrations highest near the injection point and decreasing with increasing distance. Calculated NH⁺₄ diffusion coefficients decreased with time and water content and were soil dependent. Field studies were conducted in 1983 to determine the potential germination hazard from NH₃ applied at 0, 56, 112, 168, 224, and 280 kg N ha^–1 while planting, and in 1984 to winter wheat planted 0, 1, 3, 5, 6, and 7 d after applications of 0, 100, and 200 kg N ha^–1. Stand counts, forage NO^-₃-N concentration, and yield were not influenced by NH₃ applications during planting in 1983, but grain N concentration increased linearly up to 24.1 mg g^–1 with 280 kg N ha^–1. In the 1984 experiment, increasing NH₃ rates did not decrease seedling stand, even though analysis of soil samples reflected increased soil pH and soil NH⁺₄-N concentration. Anhydrous NH₃ placement at a sufficient distance from newly seeded rows will ensure the success of systems which include NH₃ injection in conjunction with other field operations in residue management systems.

¹ Contribution from Dep. of Agronomy, Oklahoma State Univ., Stillwater, OK 74078. Approved for publication by the Director of the Oklahoma Agricultural Experiment Station as journal article no. 4950.

² Formerly Graduate Research Assistant, Dep. of Agronomy, Oklahoma State Univ., currently Extension Soil Specialist, Montana State Univ., Bozeman, MT; Professor of Soil Fertility and Plant Nutrition, and Professor of Statistics, Oklahoma State Univ., respectively.

Received for publication January 28, 1986.