Four accessions of Hordeum spontaneum and two of Hordeum vulgare were grown in pot conditions, and sampled at intervals before and after anthesis. Dry matter and nitrogen content of leaves, stems, and grains were measured. In general, H. spontaneum was characterized by higher vegetative nitrogen content, and greater allocation of dry matter resources to leaves rather than stems, compared to H. vulgare. The two small grain H. spontaneum accessions of ‘slender’ phenotypic type were much lower in leaf weight and somewhat lower in stem weight, than the two large grain ‘robust’ phenotypic types. Post-anthesis observations showed that large grain H. vulgare (cv. Ruth) accumulated grain dry matter at a greater rate (rather than duration) than the other genotypes. Final dry matter harvest index was about 26% in H. vulgare, but only 14% in all four H. spontaneum accessions. Nitrogen harvest index was low in cv. Ruth (around 35%) and high in H. spontaneum and in the high protein cultivated line 859B (all around 65%).