We evaluated the effect of 2 additives (American Farm Products, Saline, MI) on the fermentation and aerobic stability (ASb) of corn silage. Whole-plant corn (31% DM) was untreated (CN) or treated with SilagePro B, (SPB; 400,000 cfu of L. buchneri/g of fresh forage wt., 50,000 cfu of Pediococcus pentosaceus, 50,000 cfu of P. acidilactici, and isolated enzymes from Aspergillus oryzae and Bacillus subtilis including amylase, cellulase, and hemicellulose), or treated with SPB (but with a lower application rate [200,000 cfu/g] of L. buchneri (SPBL). Five replicated silos for each treatment were packed into 7.5 L silos (208 kg of DM/m³) that remained sealed until opening at 90 d of ensiling. An additional set of treatments was packed in silos with 3, 1.60-cm diameter holes plugged with stoppers and silicone glue, 2 located on the bottom of the silos at opposing ends, and one on the lid that were opened during air stress (AS) on d 14, 28, and 84. Silages were analyzed for fermentation end products and ASb (h before a 2°C increase above baseline after exposure to air at 21°C). Data were analyzed using the Fit Model in JMP (SAS Institute Inc., Cary, NC) as a 3 × 2 factorial arrangement of treatments with the main effects of treatment, air stress, and their interaction. The ASb (P < 0.001) of non-AS silages were 112, 285 and 276 h for CN, SPB and SPBL, respectively. With AS, ASb (P < 0.001) was 21, 171 and 254 h for CN, SPB and SPBL, respectively. In non-AS silages, inoculated silages had higher (P < 0.001) amounts of acetic acid and 1,2 propanediol (1,2PD) than CN. However, AS increased (P < 0.001) acetic acid in CN so it was not different from SPB but it was higher (P < 0.001) than SPBL. 1,2PD was not detected in CN that was AS and inoculated silages had high (P < 0.001) amounts of this compound. In non-AS silages, only treatment with SPBL was lower in ethanol than CN, but inoculation consistently decreased the concentration of ethanol in AS silages compared with CN. Inoculants markedly improved aerobic stability of corn silage even if air stressed during storage.