The relationships (during summer) between the water solubility of Cymbopogon-Themeda veld grass, Digitaria eriantha (finger grass) and Medicago sativa (lucerne) and their respective contents of crude protein (CP), acid-detergent fibre (ADF) and neutral-detergent fibre (NDF) were determined in samples which were collected from oesophageally fistulated steers. Highly significant (P < 0.001) linear relationships were described in all cases. Separate relationships were described for the three different herbages.