Core sampling procedure. The process of obtaining core samples involves the identification of a sample (e.g. plant, plant fraction or field plot) using a barcode row-tag (A). In this example, the second internode above-ground (red arrow) is obtained by cutting the third (B) and first (C) internodes above ground (D). The process requires reading (with a barcode scanner) and recording (with a field computer) the barcode tag and barcode tube or tubes, if multiple samples are collected (E). The core sampling device (F) is used to obtain the stalk core samples (G, H). The tubes with a perforated screw cap and the sample are dried using a freeze drier (I) and then analyzed in the high-throughput digestibility platform (J, K).