Abstract Seedlings of Pinus Mugo Turra and P. radiata D. Don were stored for periods of up to 18 weeks following different nursery bed wrenching treatments and lifting times. All seedlings were then potted and grown in controlled environment for 6 weeks before being assessed for CO2 uptake and water potential. CO2 uptake was measured using a pulse exposure of individual fascicles to air containing a known proportion of CO2 as 14CO2. Cool storage reduced the rate of CO2 uptake in both species despite water potentials normal for active gas exchange at the time of measurement. Seedlings lifted in spring showed less CO2 uptake than those lifted in midwinter, an effect compounded by storage. Wrenching did not affect CO2 uptake until after the longest storage periods for P. radiata seedlings. In a more intensive examination of seedlings after 18 weeks storage P. mugo showed a steady recovery of CO2 uptake despite initial water potentials of -16 bars, whereas P. radiata was unable to increase CO2 uptake until water potential was above -14 bars. The results suggest that there is disorganisation of the photosynthetic process during storage and that recovery is slowed by low water potential following planting. Forest Sci. 24:17-25.