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Abstract
The effect of storage temperature on the viability of sugar, Jeffrey, and ponderosa pine seed was studied to determine a suitable condition for each of the three species. Barton has reported -4° C. (25° F.) as being better for ponderosa pine than either -11° C. or -18° c. (12° F. or 0° F.), but storage temperatures have not been recommended for either sugar or Jeffrey pine seed. Before 1952, all seed stored at this Experiment Station was kept in air-tight containers at 41° F. (5° C.). However, germination tests on some seed lots, particularly sugar pine, indicated that storage at 41° F. might not be the optimum temperature for all species. Results of the present storage test indicate that seeds of all three pines maintain higher viability when stored at temperatures lower than 41° F. and that the optimum temperature differs for each.
Citation
Schubert, Gilbert H. 1955. Effect of storage temperature on viability of sugar, Jeffrey, and ponderosa pine seed. Res. Note 100. Berkeley, CA: U.S. Department of Agriculture, Forest Service, California Forest and Range Experiment Station. 3 p.
