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Grazing may be a sustainable alternative for the control of medusahead infestations but intake of medusahead by ruminants is typically low. We determined in sheep whether 1) high-energy supplements enhance medusahead intake and preference relative to no supplementation and 2) individual differences in medusahead intake influence the ingestion of a ration containing silica. Groups of lambs (n=10) were individually penned and randomly assigned to 3 supplementation treatments: 1) Control (no supplement); 2) beet pulp:barley:Ca propionate (67:30:3); or 3) beet pulp:barley:yeast culture (65:30:5). After supplementation, all animals had ad libitum access to medusahead in late vegetative to mid-reproductive (Trial 1), and late-reproductive phenological stages (Trial 2). Medusahead preferences were evaluated by offering animals a choice between medusahead and tall fescue hay. Plant part preferences were measured by offering a choice between medusahead seed heads including awns and stems+leaves. Intake of medusahead was low and cyclic, declining at the end of each trial (P < 0.0001), but there were no differences among treatments (P > 0.10). Lambs preferred tall fescue hay to medusahead. They also preferred seed heads to stems+leaves (P < 0.0001). Supplemented lambs gained more weight than Controls (P < 0.10). In Trial 3, two new groups of lambs were formed based on their intake of medusahead during Trials 1 and 2 (n=10). One group ate more medusahead and more of a ration containing alfalfa and silica (97:3) than the other (P < 0.10). Thus, supplemented lambs performed better than non-supplemented controls without reducing ingestion of medusahead. Intake of medusahead was low but a significant and consistent degree of individual variation was observed among lambs -irrespective of supplementation- in their ability to ingest medusahead and silica. This variation represents a promising option for maximizing use of medusahead by livestock foraging rangelands infested with medusahead.