Effect of Seedling Size and Transplant Bed Density on Performance of Eastern Hemlock Planting Stock

After grading two-year-old Eastern hemlock (Tsuga canadensis (L.) Carr.) seedlings by height, performance was examined for one year under various transplant bed densities, and for 2 years in the field. In the nursery, average diameter growth and dry matter production were influenced by bed density; height growth was not. A transplant bed density of 65 plants/m² (6/ft²) resulted in the greatest average diameter and dry weight, but densities up to 151 plants/m² (14/ft²) yielded more usable transplants per unit of nursery bed. Although there were residual effects of transplant bed density, the major differences in growth after 2 growing seasons in the field were due to initial seedling size. Transplants originating from large seedlings outperformed those from small seedlings. Compared to small seedlings, larger plants require less time in transplant beds, are less troublesome to maintain in the field, and reach marketable size in fewer years, all of which increase their value relative to small seedlings.