A total of 28 samples of wheat, oat and barley straws showed a wide range in concentration of nitrogen, ash, gross energy, neutral detergent fibre, acid detergent fibre, lignin, cellulose, hemicellulose, residual ash, calcium, magnesium, sodium, potassium and phosphorus. Four straws that had suffered rain damage before collection ranged in in vitro organic matter digestibility from 25 to 34%, compared with 30 to 49% for the other straws; after treatment with 6 g NaOH per 100 g dry matter the ranges were 42 to 46% and 43 to 62%, respectively. The need to determine the effects of the various factors affecting straw quality is emphasized.