EFFECT OF ANNUAL LOW-NITROGEN FERTILIZATION OF CRESTED WHEATGRASS

Abstract

In this study, we sought to determine the effect of low-level nitrogen fertilization in the rejuvenation of old stands of crested wheatgrass [Agropyron desertorum (Fisch. ex Link) Schult.] to increase dry matter production. Spring and fall applications of 0, 22, and 34 kilograms N/hectare were evaluated for their effect on total dry matter (TDM) production, crude protein concentration, and water use efficiency (WUE). Fertilizer treatment effects on the TDM and crude protein of the forage were very erratic and inconsistent. Nitrogen analysis of plant litter and soil showed significantly more residual N on the fertilizer treatments, compared with the control, but the N was apparently immobilized. These low-level fertilizer applications of 22 and 34 kg N/ha appeared to be too low for crested wheatgrass rejuvenation under the conditions of this study. In this study, we sought to determine the effect of low-level nitrogen fertilization in the rejuvenation of old stands of crested wheatgrass [Agropyron desertorum (Fisch. ex Link) Schult.] to increase dry matter production. Spring and fall applications of 0, 22, and 34 kilograms N/hectare were evaluated for their effect on total dry matter (TDM) production, crude protein concentration, and water use efficiency (WUE). Fertilizer treatment effects on the TDM and crude protein of the forage were very erratic and inconsistent. Nitrogen analysis of plant litter and soil showed significantly more residual N on the fertilizer treatments, compared with the control, but the N was apparently immobilized. These low-level fertilizer applications of 22 and 34 kg N/ha appeared to be too low for crested wheatgrass rejuvenation under the conditions of this study. © Williams & Wilkins 1982. All Rights Reserved.