Comparison of the Initial Growth of Different Poplar Clones on Four Sites in Western Slovakia—Preliminary Results

Abstract

This study was conducted to evaluate four hybrid poplar comparison tests along a groundwater availability gradient in Western Slovakia. The weather fluctuation during the 3-year study period was described with indices, such as the Forestry Aridity Index (FAI) or the hydrothermal coefficient (HTC). The soil chemical and physical parameters were determined from soil samples from the two upper horizons. The nutrient status and supply of the trees were categorized based on leaf elemental analysis. Altogether, 21 different clones from 6 genomic groups were compared. The survival (SRV), diameter at breast height (DBH), and height of the trees (H) had been measured annually since the plantations were established, and from these measurements, mean annual height increment (MAHI) values were derived. These weather, edaphic, and clonal factors were evaluated and compared. Significant effects of the site (edaphic factors) were found as the primary source of variance and clonal differences as secondary sources of variance among the growth of trees. The interaction of site × clone effects was not significant. The results showed that for short rotation forestry (SRF), the site parameters—especially groundwater availability—are key factors.

Responses of radial growth, wood density and fiber traits to planting space in poplar plantations at a lowland site

“…Furthermore, compared to the results at a lowland site reported by Fang et al (2021), poplar growth rate in this study is much lower owing to differences in clones and water table levels between the two sites. Our results are in agreement with previous reports that both groundwater levels and soil moisture impact radial growth of different tree species (Orwig and Abrams 1997;He et al 2020;Heilig et al 2021). Likewise, the significant effect of plant spacing on WD was found in the present study at the stand age of 13, which is inconsistent with some reports of wood air-dry density and oven-dried density for conifer species (Lasserre et al 2009;Watson et al 2011) where WD was not significantly influenced by plant spacings, confirming that, except for spacing, wood air-dry density (density when wood is equilibriated to 40% RH and 20 °C; equivalent to 7-8% moisture content) is affected by other factors such as species, genotype and site conditions (Pliura et al 2007).…”

Survival and juvenile-age performance of Salicaceae clones for biomass

“…In some studies, (Orlandi et al, 2017), data from the first year are not even used when comparing the growth potential of different clones. In a study conducted in western Slovakia (Heilig et al, 2021) collating the growth and survival of 21 poplar clones on 4 sites, even after 3 years of growth, significant differences between clones were found in only one of the sites. On the other hand, when comparing four poplar clones in an experiment conducted in Latvia, interclone differences were found after the second but not after the third year of growth (Lazdiņa et al, 2014).…”

Manipulating grading strategy for the efficient harvesting of industrial poplar plantations

“…Both plantations were 5-year-old poplar stands established at a square spacing of 3.0 m x 2.0 m with the hybrid poplar (Populus x euramericana Dode (Guinier)). Clone 'AF16' was planted in Nivky, and clone 'AF18' in Gajary (Heilig et al 2021, Landgraf et al 2020, Meyer et al 2021.…”