Coastal bermudagrass and Renner lovegrass fertilization responses in a subtropical climate

Forage production in subtropical regions usually requires fertilization to meet plant nutrient needs. This study was conducted to determine the influence of N and P application on yield response, nutrient uptake, and apparent fertilizer and water use efficiency of 2 grasses on a subtropical coastal prairie. Treatments consisting of factoral combinations of 0, 112, and 224 kg N/ha and 0, 15, and 29 kg P/ha were annually applied to coastal bermudagrass (Cynodon dactylon (L.) Pers.) and Renner lovegrass (Eragrostis curvula (Schard.) Ness) on a Sarita fine sand (grossarenic paleustalf) in South Texas. Cuttings were made 2 to 4 times per year for 4 years. Soil samples taken annually and plant samples from each cutting were analyzed for N and P concentration. Forage yields by both grasses improved dramatically with N application, but to a much lesser degree with P application. While yields were also strongly dependent on rainfall level, N substantially improved forage yield per unit of rainfall received. Forage concentration of both N and P increased with increasing application rates of each nutrient. Apparent fertilizer recovery fluctuated between years, reflecting stand age and rainfall; however, fertilizer rate had no effect. None of the fertilizer N not removed in the forage could be found as inorganic N at the 0 to .3-m soil depth, while up to 20% of the P applied remained available in the soil. Between 65 and 80% of the fertilizer applied was not used by the forage grasses. Improvements in forage yield and quality with N and P fertilization justify their use, even though inefficiency of fertilizer recovery and use is substantial.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact lbry-journals@email.arizona.edu for further information.Migrated from OJS platform August 202