Differences in growth and wood properties between narrow and normal crowned types of Norway spruce grown at narrow spacing in Southern Finland

Abstract

In recent years there has been increased interest in the so called narrow crowned Norway spruce (Picea abies f. pendula), which is a rare mutant of Norway spruce (Picea abies (L.) Karsten), as a suitable wood raw material source for pulp and paper production. This is because it is less sensitive to competition than the normal crowned Norway spruce, and thus, could be more productive especially at dense spacing. In the above context, we investigated how the growth and yield (such as height, diameter, stem volume and ring width) in addition to wood density traits and fibre properties (such as wood density, fibre length and width, cell wall thickness and fibre coarseness) were affected in trees from 9 full-sib families representing narrow crowned Norway spruce grown at narrow spacing of 1 m × 1 m in Southern Finland. For comparison, we used normal crowned Norway spruce trees from 6 breeding regions.We found that, compared to growth and yield traits, wood density traits and fibre properties showed, on average, lower phenotypic variations. In addition, these variations were smaller for narrow crowned families than for normal crowned genetic entries. Narrow crowned families also showed, on average, higher growth and yield and fibre length, but lower wood density. Moreover, the phenotypic correlations between growth, yield, wood density traits and fibre properties, ranged, on average, from moderate (narrow crowned) to high (normal crowned). As a whole, the growth and wood properties of narrow crowned families were found to be less sensitive to tree competition than the normal crowned genetic entries used as a comparison.

Adaptability of Narrow-Crowned Norway Spruce Ideotype (Picea abies (L.) Karst. pendula Form) in 25 Years Half-Sib Comparative Trials in the Eastern Carpathians

“…The Finnish results were obtained at the same trees' age, on a favourable site condition for Norway spruce and on a planting scheme a little denser than ours, 2 m × 1.5 m [34]. In Finland, in a thinning experiment (1 m × 1 m), wood density was lower for narrow crowned than for normal crown spruce trees [33] while the growth traits were higher, suggesting superior adaptability of narrow crowned form to the denser planting scheme. The same as in the present work, previous research has reported a much smaller variation for wood density than growth traits [57,58].…”

“…The research from Finland indicates some particularities of narrow crowned spruce: low and irregular flowering, the pendula character of branches can be observed around the age of six years when the plants reach a height of 1 m, and in the case of generative multiplication (much cheaper) only a half of the descendants inherit the character. Zubizarreta Gerendiain and collaborators [33,34] draw attention to the plasticity of the narrow crown spruce when increasing the planting distance between seedlings, this variety being indicated especially in the case of dense planting schemes, 1 m × 1 m or 1 m × 1.5 m, while in a 2 m × 1.5 m device the pyramidal spruce grow much better (the average volume being double at the age of 20 years). The adoption of more dense planting schemes for narrow crown spruce is the conclusion reached by Kuuluvainen's research [35].…”

Can wood properties be predicted from the morphological traits of a tree? A canonical correlation study of plantation-grown white spruce

“…Tree diameter and height were identified as having the highest correlations with most crown morphological traits, and they are the morphological variables representing the best correlations with wood traits. Zubizarreta Gerendiain et al (2008) reported similar high correlations between traits related to cell anatomy and DBH, as well as tree height of Norway spruce.…”

Assessing the wood quality of interior spruce (Picea glauca × P. engelmannii): variation in strength, relative density, microfibril angle, and fiber length

“…However, tree characteristics such diameter at breast height (DBH), crown length, and stem taper have all also been shown to affect wood strength attributes of black spruce (Liu et al 2007). Crown form may also affect wood properties: Zubizarreta Gerendiain et al (2008) found that the narrow crowned mutation in Norway spruce leads to lower wood density (WD) but greater fiber length than in trees that possess normal crown attributes.…”