Correlation between Height: diameter Ratio and Shoot Growth in Containerised and Bare-root Seedlings of <i>Cryptomeria japonica</i>

Abstract

2016 Correlation between Height:diameter Ratio and Shoot Growth in Containerised and Bare-root Seedlings of Cryptomeria japonica. J Jpn For Soc 98: 139 145 Previous studies revealed that in terms of the stem height growth, containerised seedlings with an average height:diameter ratio HDR of ca. are superior to conventional bare-root seedlings and containerised seedlings with an average HDR of ca. are inferior to conventional bare-root seedlings. In this study, we focused on the correlation between the stem growth and HDR in individual seedlings. We measured the stem growth of-year-old containerised seedlings and-year-old conventional bare-root seedlings for four growth seasons. In each of the growth seasons, HDR showed a negative correlation with stem height growth rate and a positive correlation with the stem radial growth rate of an individual seedling; the strongest correlation was observed in the first and second growth seasons. Therefore, the seedling with a high HDR allocated resources to stem radial growth rather than to height growth. Regarding the stem height growth, we analysed the sequential data for four growth seasons using a linear mixed effects model. HDR showed a negative correlation with the stem height growth. In conclusion, high HDR had negative effects on not only the relative height growth rate but also on the actual height growth.

Effects of Seedling Size, Stock Type, and Mechanical Site Preparation Method on Initial Survival and Growth of Japanese Larch (Larix kaempferi) Seedlings

“…The RGR of height of bareroot (1+2) seedlings was low until the second GS (Figure 5A), while that of RCD was comparable to the other stock types in the second GS (Figure 5B), suggesting that bareroot (1+2) seedlings preferred RCD growth to height growth until the proper height:RCD ratio was reached. Similarly, the negative effect of high height:RCD ratio on initial height growth has also been reported in Japanese cedar [43] and Austrian pine [44]. The bareroot (1+2) seedlings in the current study were leftover bareroot (1+1) seedlings, which are commonly used in Japan.…”

Eight-year survival and growth of Sakhalin fir (Abies sachalinensis) seedlings with one weeding operation: Impact of mechanical site preparation, vegetation release, summer planting, stock type, and forwarder trail

“…Equivalently sized container seedlings can perform equally well (Thiffault et al 2014) or even outperform bareroot seedlings (Morrissey et al 2010). The smaller container seedlings with a higher H:D ratio at planting tend to prioritize diameter growth over height until reaching a more balanced ratio (Yagihashi et al 2016;Ivetic et al 2017;Harayama et al 2023a). In this study, container seedlings with higher H:D ratio (Fig.…”

Eight-year survival and growth of Sakhalin fir (Abies sachalinensis) seedlings with one weeding operation: Impact of mechanical site preparation, vegetation release, summer planting, stock type, and forwarder trail

“…3c). Seedlings with a heightened H:D ratio defer height growth in favor of diameter growth until an appropriate H:D ratio is attained (Yagihashi et al, 2016;Ivetic et al, 2017;Harayama et al, 2023a). In this study's second year, container seedlings displayed high RGR D (Fig.…”