It has been shown that various biomass species requires different AFEX pretreatment conditions in order to get higher sugar yields.  Also, within a given biomass species, pretreatment conditions may vary depending upon the cultivar, and when and where the feedstock was harvested.  Therefore, the AFEX pretreatment itself must be as consistent and repeatable as possible.  We have applied the AUTOPLANT®, manufactured by Chemspeed Technologies, Inc, Monmouth Junction, N.J. to the AFEX pretreatment of Corn Stover. The AUTOPLANT® is an automated platform which will hold six  ChemSpeed's MiniPlant modules (12 reactor vessels total). Each MiniPlant consists of two individually controlled 100 mL stainless steel reactors with stirrers. It has a robotic arm to deliver a precise amount of water to the biomass in the reactor. We believe that the AFEX pretreatment can be done under controlled conditions (including temperature, pressure, ammonia/water delivery and residence time) using the AUTOPLANT®.  The first of its kind, the AUTOPLANT® will quickly identify the optimal AFEX conditions for a given batch of biomass based on maximum sugar conversion using enzymatic hydrolysis. In this work, we will provide results of AUTOPLANT® pretreated corn stover which can comparable to, if not superior to the known results of previous AFEX pretreatment work using corn stover as a substrate.