Collection Age and Seed Mass Influence Germination and Seedling Growth in Midwestern White Spruce Accessions

Stored tree seed collections are essential resources for seedling production and conserving unique germplasm. As stored seeds age, however, seed viability and seedling vigor can decline. This study tests how age and seed mass correspond to germination dynamics and seedling vigor in four white spruce collections from the upper midwestern United States. Using two seedling growth experiments, this study demonstrates that white spruce seeds stored for >30 years have low seed viability and slower seedling growth rates compared with seeds from more recent (≤10 years) white spruce collections. Seed mass also predicted seedling growth rate regardless of collection age, suggesting larger seeds from older collections generate faster growing seedlings.