Wood chips of 0.3 and 2 mm depth from poplar and spruce wood samples, respectively, were degraded by using glycerol as a solvent and alkaline glycerol with and without Na2CO3 and NaOH catalysts at different degradation temperatures: 440, 450, 460, 470, 480, 490 and 500 K. By products from the degradation processes of the lignocelluloses include lignin degradation products. Lignin and its degradation products have fuel values. The total degradation degree and cellulose degradation of the wood chips were determined to find the relationship, if any, between the yields of total degradation degree (YTD) and degradation temperature (T). There is a good linear relationship between YTD or the yields of cellulose degradation (YCD) and T (K). For the wood samples, the regression equations from NaOH (10%) catalytic runs for 0.3 mm x 15 mm x 15 mm chip size are: For poplar wood: YTD = 0.7250T - 267.507 (a) YCD = 0.1736T - 71.707 (b) For spruce wood: YTD = 0.2650T - 105.979 (c) YCD = 0.0707T - 27.507 (d) For Eqs. (a), (b), (c) and (d), the square of the correlation coefficient (r(2)) were 0.9841, 0.9496, 0.9839 and 0.9447, respectively. (C) 2003 Elsevier Ltd. All rights reserved.