*2.1. Materials*

A raw corn stover bale from Kadolph Farms in Hardin, Iowa was deconstructed in the process development unit (PDU) of the Idaho National Laboratory's Biomass Feedstock National User Facility (BFNUF). The bale was harvested in the fall of 2018 using an 8 row stripper header and raked using rotary tedder prior to baling. Bales were stored immediately after baling in stacks at the field edge with a six-high by three-length stacking position. Size reduction in the BFNUF was accomplished using a Vermeer prototype horizontal bale grinder (BG480, Pella, Iowa) with a 15.24 cm screen. This mill was powered by two 200 HP electric motors with 96 swinging hammers on each of the two grinding drums. The sample, referred to as ORG CS hereafter, was dried below 10 wt. % moisture content prior to AC and HTC treatments.
