USDA LTAR Common Experiment measurement: Concentration of nutrients and in vitro organic matter digestibility in plant tissue v1

The overarching objective of plant tissue sampling in LTAR common experiments is to quantify the chemical composition of plant species, with particular regard to elements (N and P) or digestibility by grazing animals (e.g. In vitro organic matter digestibility (IVOMD) that may limit agroecosystem function and goods/services provision. Plant tissue composition data have broad applicability. They can be used to understand spatial and temporal variation in plant nutrient content and supply, identify the extent to which one or more mineral elements may limit crop and rangeland plant growth, and determine the influence of management, disturbance regimes, climate, or edaphic factors on crop and rangeland productivity, ecosystem services, commodity quality and nutritional value. Plant tissue nutrients are also important for understanding ecosystem nutrient use efficiency and are a complement to soil nutrient analyses. Measurements can be taken at the leaf, whole plant, or community level depending on the research objective at the site.