AbstractVoluntary intake andin vivodigestibility of herbage harvested from five indigenous communities–Agrostis‐Festuca, NardusandMoliniagrasslands andEriophorum vaginatum‐andTrichophorum caespitosum‐dominated varieties of blanket bog–and also from sownLolium perenneandTrifolium repensswards were measured over two years. First growths of each sward were harvested at three stages of maturity and stored at — 20°C before feeding. Voluntary intake was measured while feedingad libitumto 15% excess of the intake on the previous day and digestibility when feeding at 80% of voluntary intake.There was a common positive relationship (r2= 0·86***) between intake (adjusted for year of feeding, range 72·8–16·7 g organic matter (kg LW)0·75d‐1) and organic matter digestibility (range 0·796–0·371), coveringLolium perenneand most of the indigenous communities. However, there were significant differences between the regressions of intake on the concentration of neutral detergent fibre for ryegrass and the indigenous communities, and also between the regressions for individual communities.The results demonstrated the general value of organic matter digestibility as a predictor of intake potential, and the high digestibility and intake potential of immature vegetation from the grass and