In vivo digestibility trials were carried out using six young rams fed with Atriplex halimus biomass harvested in summer (A) and in early autumn (B), and with a mixture of mid-autumn Atriplex halimus and wheat straw (5[ratio ]1 ratio on fresh matter basis) (C). Atriplex halimus had a high protein content (139·0, 135·9 and 193·4 g/kg DM in A, B and C respectively), but was rich in sodium chloride, especially in summer (145·9 g/kg DM), limiting its use as feed. The summer forage had a higher organic matter (OM) digestibility coefficient than the autumn forage (0·663 v. 0·530) but lower digestible OM intake (16·8 v. 29·4 g/day per kg BW0·75). In autumn forage, the combination with straw did not influence the digestibility of organic matter, whereas it enhanced DOM intake in comparison with the Atriplex halimus on its own (35·7 v. 29·4 g/day per kg BW0·75).