Callus derived from stem segments of loblolly pine (Pinus taeda L.) was subcultured to media containing 0.5% of various mono-, di-, tri- or polysaccharides. None of the carbohydrate sources tested were superior to sucrose. Growth on twelve of the 20 carbohydrates tested was more than 75% of that obtained for sucrose; growth on two other carbohydrates became >75% of the value for sucrose by the second interval on the new carbon source. Ribose and galactose-containing sugars are among those which support pine callus growth. Dramatic differences in ribose utilization are noted on media supplemented with glutamine vs. NH4/NO3 nitrogen sources.