Poultry litter and inorganic fertilization: Effect on biomass yield and nutrient concentration of three mixed - season perennial forages

Authors: JAJA, NGOWARI - Oak Ridge Institute For Science And Education (ORISE); CODLING, ETON - Retired ARS Employee; RUTTO, LABAN - Virginia State University; Timlin, Dennis; Reddy, Vangimalla

Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/22/2022
Publication Date: 2/22/2022
Citation: Jaja, N., Codling, E., Rutto, L., Timlin, D.J., Reddy, V. 2022. Poultry litter and inorganic fertilization: Effect on biomass yield and nutrient concentration of three mixed - season perennial forages. Agronomy Journal. 12:570. https://doi.org/10.3390/agronomy12030570.
DOI: https://doi.org/10.3390/agronomy12030570

Interpretive Summary: We conducted a two-year field study to determine the impact of poultry litter and fertilizer application on two warm season and one cool season forage crops. We examined the ability of stinging nettle to remove excess nutrients and produce forages when compared with traditional forages such as bermudagrass and switchgrass when grown on poultry litter and fertilizer amended soil. Each crop was cut five times where possible during the year. The forage, and soil samples were analyzed for trace metals and nutrients such as Calcium (Ca), Copper (Cu), Iron (Fe), Potassium(K), Magnesium (Mg), Manganese (Mn), Phosphorus(P), lead (Pb) and Zinc (Zn) using the Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES). Results showed that the total biomass yield was higher by 66% in bermudagrass and 58% in switchgrass compared with stinging nettle for the first year. The bermudagrass and the switchgrass produced more biomass at their peak growth in the summer than the stinging nettles which grew better in cool weather. Metal concentrations of all the elements was higher in the stinging nettle compared to the bermudagrass and switchgrass when averaged over the two years. With the higher nutrient content and high biomass in the cooler weather, stinging nettle could be a useful plant for forage and nutrient cycling, especially when it is grown with warm season forage crops.

Technical Abstract: The effect of poultry litter and inorganic fertilizer applications on three mixed season perennial forages was studied for two years in the field, to determine biomass yield and nutrient concentration. The primary objective was to investigate the trace metal and nutrient removal as well as the forage potential of stinging nettle (Urtica dioica L.) relative to two traditional warm season grass forages, bermudagrass [Cynodon dactylon L. (Pers.)] and switchgrass (Panicum virgatum L.). Employing five specified harvests or cuttings where applicable, forage and soil samples were analyzed for trace metals and nutrients (Ca, Cu, Fe, K, Mg, Mn, P, Pb and Zn) using the Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES). Results indicate that the total biomass yield was higher by 66% and 58% in bermudagrass and switchgrass respectively compared with stinging nettle for the first year. While the warm season grasses yielded more biomass at their peak over the cool season forage, the metal concentration reveals a significantly higher concentration of all the elements in the cool season than in the warm season forage samples. Nutrient concentrations were also higher in the stinging nettle over the two years or seasons, but were within the allowable limits for forages, indicating its potential as a versatile resource for forage and nutrient cycling, particularly when double cropped with a warm season forage crop. Keywords: Forage crops, Trace Metals, Poultry Litter, Biomass Yield, Nutrient Uptake