Abstract This study assessed forage yield and chemical composition, feed intake, and performance of beef heifers grazing intermediate wheatgrass (IWG) regrowth post-grain harvest compared with a stockpiled grass/legume control in the late fall. Pastures were established in 2020 at Glenlea, MB, Canada and treatments were: 1) Courtenay tall fescue/Algonquin alfalfa/Oxley II cicer milkvetch (50:25:25; FORCON); 2) IWG, pure stand, no fertilizer post establishment (NFERT); 3) IWG, pure stand+50 kg N· ha-1 post-grain harvest (FERT); 4) IWG with Alsike clover (50:50; AL). The FORCON and IWG treatments were harvested in June (hay) and August (grain) 2021, respectively. Thirty-two beef heifers were assigned to eight paddocks, four heifers per paddock in a randomized complete block design with two blocks. Each block had four paddocks, each paddock receiving one of the four treatments. Heifers began grazing on Oct 6 for a 14-d adaptation period and a 22-d experimental period. Forage samples were obtained once every 2 weeks and analyzed for CP and TDN. Individual feed intake was estimated using the titanium oxide method with fecal samples collected on d 21 and 22 and pooled. Bodyweight and blood samples (blood urea nitrogen, BUN) were obtained on d 1 and d 22. Data were analyzed using a mixed model in R studio, with the fixed effect of forage treatment and the random effects of block and paddock. Forage yield and CP were greater for FORCON (3,515 kg· ha-1 and 14.9% DM, respectively) than the IWG treatments (mean 2778 kg· ha-1 and 12.83% DM, respectively), which did not differ (P < 0.0001 and P = 0.150, respectively). The TDN was less for FORCON (60.6% DM) than IWG treatments (mean 61.5% DM), which did not differ (P = 0.394). Dry matter, CP and TDN intake were lower for FORCON (7.91 kg· DM d-1, 1.15 kg· DM d-1, 4.98 kg· DM d-1, respectively) than IWG treatments (mean 8.54 kg· DM d-1, 1.16 kg· DM d-1, 5.44 kg DM d-1), which did not differ (P = 0.237, P = 0.218, P = 0.137, respectively). The ADG was less for FORCON (0.53 kg· d-1) than IWG treatments (mean 0.77 kg· d-1), with the greatest gains observed in IWG AL (0.90 kg d-1; P = 0.046). Blood urea nitrogen was greater for FORCON (3.95 mmol· L-1) than IWG treatments (mean 3.78 mmol· L-1), which did not differ (P = 0.203) on d 1. However, on d 22 the opposite response was observed with decreased BUN in FORCON (2.97 mmol ·L-1) than in IWG treatments (mean 3.51 mmol· L-1), which did not differ (P = 0.350). In conclusion, IWG offered comparable performance as a feed alternative to the conventional perennial grass/legume mix commonly used for extended grazing. However, the effects of fertilizer or legume on IWG may differ under different soil conditions due to high fertility at the experimental site.