Survival and shoot growth of containerized and bare-rooted seedlings of Picea jezoensis during three years after planting

Abstract

Recently, containerized seedlings attract attention due to their planting efficiency and rooting success compared to bare-rooted seedlings. However, the survival rate and growth of containerized seedlings in Hokkaido might show different tendency since naturally-distributed conifers grow slowly at the early stage in Hokkaido and the forest floor is densely covered by dwarf bamboos. We planted 4-year-old containerized seedlings, two kinds of 3-year-old containerized seedlings, and 7-year-old bare-rooted seedlings in autumn 2010 and in spring 2011. Then, their survivorship, height, and root color diameter were investigated during three years after planting. The two kinds of 3-year-old containerized seedlings have exhibited significantly lower rate in survival and shoot growth than the 4-year-old containerized seedlings and 7-year-old bare-rooted seedlings. In contrast, the survival rate is not significantly different between the 4-year-old containerized seedlings and 7-year-old bare-rooted seedlings after three years. Height and diameter growth of the 7-year-old bare-rooted seedlings were larger than those of the 4-year-old containerized seedlings at the third growing period, although they were similar level between them at the first and second growing period.