Two experiments were conducted to evaluate the impact of (1) ensiling on kernel processing score (KPS; % of starch passing through 4.75 mm sieve) of whole-plant corn silage (WPCS) of varied processors and settings; and (2) extended ensiling times on KPS of corn shredlage. In Experiment 1, samples from 2 self-propelled forage harvesters (SPFH) were collected at harvest. One SPFH was fitted with a conventional-type processor with greater (32% vs. 21%) roll-speed differential than normal. Samples collected were from 3 theoretical lengths of cut (TLOC; 19, 22 and 26 mm; 3-mm roll-gap setting) in 2 hybrid types (leafy and dual-purpose). The other SPFH was fitted with an intermeshing-disc processor and samples were from 3 TLOC (17, 19 and 26 mm) at 2 roll-gap settings (1.5 and 2.5 mm) in one hybrid. Samples for each processor and settings collected at harvest (12 samples total) were divided into 2 piles. The first pile was unfermented and analyzed for KPS in duplicate. The second pile was vacuum-sealed in 3 plastic bags and ensiled for 30 d. After fermentation, the 3 bags were composited and analyzed for KPS in duplicate. Data were analyzed using Proc Mixed of SAS with the fixed effect of fermentation and the random effect of sample. In Experiment 2, WPCS was harvested using a SPFH fitted with a shredlage processor with cross-grooved rolls set at 2.5 mm roll-gap and 32% roll speed differential and the SPFH set at 26 mm of TLOC. Samples were collected at harvest and vacuum-sealed in plastic bags and ensiled for 0, 30, and 120 d in triplicate. Samples from each bag were analyzed for KPS in duplicate. Data were analyzed using Proc Mixed of SAS with the fixed effect of ensiling time and the random effect of bag. In Experiment 1, ensiled samples had 10%-units greater (P = 0.01) KPS than the unfermented samples (60.1% vs. 50.2%, respectively). In experiment 2, WPCS ensiled for 120 d tended (P = 0.07) to have 7%-units greater KPS than 0 d (67.2% vs. 60.3%, respectively), but not 30 d (63.6%). These findings suggest that fermentation increases KPS.