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Medusahead grass (Taeniatherum caput-medusae) is an invasive weed that reduces wildlife habitat, biodiversity, and ecological services. It has been shown that sheep increase intake of and preference for foods of low palatability when ingested in close temporal association with foods of greater nutritional quality. This study explored the effect of a high-energy supplement on medusahead use by ewes with their lambs on medusahead-infested rangeland. Three ewes with their lambs (1-2) were randomly assigned to each one of 12 groups, 6 groups ate an energy-based supplement   (1.5 kg/group; beet pulp:barley:Ca-propionate, 66:30:4) in the morning and all groups grazed during the early boot stage through the dough stage of medusahead for 15 days. Plant biomass and relative proportion of species composition were estimated pre- and post-grazing. Eleven medusahead quadrats (0.0087m²)/plot were marked to record the percentage of quadrats with bitten tillers and percentage of bitten stems/quadrat during day 5, 10, and 15 of grazing. According to pre- and post- grazing biomass,  supplemented and non-supplemented sheep removed on average 1.7 and 1.3 kg DM of forage/day (P = 0.19), respectively. Supplemented and non-supplemented sheep removed 80 vs. 55, 254 vs. 61, and 1246 vs. 977 g MS/animal/day of medusahead, thatch and forbs, respectively (P > 0.05). Supplemented animals showed bites on the 71, 87, and 93% of quadrats during the sampling period, whereas non-supplemented animals displayed bites on the 49, 77, and 87% of the quadrats (P > 0.05). The percentages of bitten tillers of medusahead for supplemented and non-supplemented animals were 47 vs. 29, 82 vs. 64, and 87 vs. 75% (P < 0.05) on each sampling date. This information suggests that sheep can consume medusahead in a diverse plant community and that an energy-based supplement stimulated use of medusahead in the community.