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Legacy Phosphorus and Potassium Correlation Experiments: Qulin, Missouri

    Correlation experiments for P and K were conducted from 1968-1973 at a research farm in Qulin, Missouri to better define the relationships between soil tests, crop yields, and fertilizer treatments. Three crop rotations each were conducted for P and K trials (ranges C, D, E, F, G, and H), and included corn, soybean, wheat, cotton, and sorghum.

    Alfalfa Response to Potassium Rate and Timing of Application

      Alfalfa production is a key component of livestock production in Tennessee. Alfalfa has the ability to take up luxury amounts of potassium, which can lead to high plant tissue K concentrations and lower concentrations of other nutrients. The objectives of this research were to determine 1) whether Tennessee K recommendations for alfalfa were sufficient and accurate, and 2) if splitting K applications impacted alfalfa yield.

      Data from: Feasibility of Infiltration Galleries for Managed Aquifer Recharge in the Mississippi River Valley Alluvial Aquifer of Northeast Arkansas

        The information in this dataset is from "Feasibility of Infiltration Galleries for Managed Aquifer Recharge in the Mississippi River Valley Alluvial Aquifer of Northeast Arkansas" by Godwin et al., 2020. Included in the dataset are the following raw data: Table of well log point; Raw geophysical data files; Soil sample textural analysis data; Soil sample chemical analysis data.

        Data from: A database for global soil health assessment

          The SoilHealthDB database integrates soil health measurements conducted in the field from sites across the globe. SoilHealthDC currently focuses on four main conservation management methods: cover crops, no-tillage, agro-forestry systems, and organic farming. These studies represent 354 geographic sites (i.e., locations with unique latitudes and longitudes) in 42 countries around the world. The SoilHealthDB includes 42 soil health indicators and 46 background indicators that describe factors such as climate, elevation, and soil type.


            Root Zone Water Quality Model 2 (RZWQM2) is a whole-system model for studying crop production and environmental quality under current and changing climate conditions. It emphasizes the effects of agricultural management practices on physical, chemical and biological processes. RZWQM2 is a one-dimensional model with a pseudo 2-dimensional drainage flow. Crop simulation options include the generic plant growth model, DSSAT-CSM 4.0 and HERMES SUCROS models. It also can simulate surface energy balance with components from the SHAW model and water erosion from the GLEAMS model. An automated parameter estimation algorithm (PEST) was added to RZWQM2 for objective model calibration and uncertainty analysis.

            Data from: Starch and dextrose at 2 levels of rumen-degradable protein in iso-nitrogenous diets: Effects on lactation performance, ruminal measurements, methane emission, digestibility, and nitrogen balance of dairy cows.

              This feeding trial was designed to investigate two separate questions. The first question is, “What are the effects of substituting two non-fiber carbohydrate (NFC) sources at two rumen-degradable protein (RDP) levels in the diet on apparent total-tract nutrient digestibility, manure production and nitrogen (N) excretion in dairy cows?”. This is relevant because most of the N ingested by dairy cows is excreted, resulting in negative effects on environmental quality. The second question is, “Is phenotypic residual feed intake (pRFI) correlated with feed efficiency, N use efficiency, and metabolic energy losses (via urinary N and enteric CH4) in dairy cows?”. The pRFI is the difference between what an animal is expected to eat, given its level of productivity, and what it actually eats. The goal was to determine whether production of CH4, urinary N or fecal N is a driver of pRFI.