EJPAU 2008. Barszcz A. , Gjerdrum P. THE ZONALITY OF OCCURRENCE OF KNOTS AND RELATIONS BETWEEN THEIR LOCATION AND SIZE IN LARGE-DIMENSIONED SPRUCE STEMS IN SOUTH-EASTERN NORWAY

Electronic Journal of Polish Agricultural Universities (EJPAU) founded by all Polish Agriculture Universities presents original papers and review articles relevant to all aspects of agricultural sciences. It is target for persons working both in science and industry,regulatory agencies or teaching in agricultural sector. Covered by IFIS Publishing (Food Science and Technology Abstracts), ELSEVIER Science - Food Science and Technology Program, CAS USA (Chemical Abstracts), CABI Publishing UK and ALPSP (Association of Learned and Professional Society Publisher - full membership). Presented in the Master List of Thomson ISI.

2008
Volume 11
Issue 3/volume11

Topic:

Forestry

ELECTRONIC
JOURNAL OF
POLISH
AGRICULTURAL
UNIVERSITIES

Barszcz A. , Gjerdrum P. 2008. THE ZONALITY OF OCCURRENCE OF KNOTS AND RELATIONS BETWEEN THEIR LOCATION AND SIZE IN LARGE-DIMENSIONED SPRUCE STEMS IN SOUTH-EASTERN NORWAY, EJPAU 11(3/volume11), #05.
Available Online: http://www.ejpau.media.pl/volume11/issue3/volume11/abs-05.html

THE ZONALITY OF OCCURRENCE OF KNOTS AND RELATIONS BETWEEN THEIR LOCATION AND SIZE IN LARGE-DIMENSIONED SPRUCE STEMS IN SOUTH-EASTERN NORWAY

Anna Barszcz¹, Peder Gjerdrum²
¹ Department of Forest and Wood Utilization, Agricultural University of Cracow, Poland
² Norwegian Forest and Landscape Institute, Ås, Norway

ABSTRACT

The present research concerned selected
characteristics of knottiness of large-dimensioned spruce timber (of trees with
the minimum breast-height diameter of 40 cm over bark) from three stands, over
one hundred years old, located in south-eastern Norway. Fourteen sample trees
were felled and measured, and knots which occurred in them were classified into
three categories of healthiness and three categories of tightness with the surrounding
wood. Sound and tight knots were dominant in the timber under analysis. All categories
varied significantly in relation to average diameters, relative diameters (related
to stem thickness at the points where the knots occurred) and the relative height
of location along merchantable boles. The researches analysed the significance
of relations of diameters or relative diameters of knots with the relative height
of their location along merchantable boles. The relations, confirmed by coefficients
of correlation close to or higher than 0.50 were described by equations of regression,
most often by the expotential model. The frequency of occurrence of knots of
different categories in sections of 0.1 of merchantable bole length allowed for
distinguishing characteristic quality zones on the spruce stems: from the tree
bottom to 0.3 of merchantable bole length inclusive, from 0.4 to the upper end
of a merchantable bole – in respect of knot healthiness; as well as from the
tree bottom to 0.3, from 0.4 to 0.6 and from 0.7 to the upper end of a merchantable
bole – in respect of tightness of knots with surrounding wood. The results were
compared with analogous data obtained earlier for spruce timber in mature stands
in the Polish Beskidy Mts.

Key words: large-dimensioned spruce timber, Norway, categories of knots, diameters of knots, location on stems, quality zones.

Anna Barszcz
Department of Forest and Wood Utilization,
Agricultural University of Cracow, Poland
Al. 29 Listopada 46, 31-425 Cracow, Poland
Phone: +48 12 662 50 85
email: rlbarszc@cyf-kr.edu.pl

Peder Gjerdrum
Norwegian Forest and Landscape Institute, Ås, Norway
1432 Ås, Norway
email: peder.gjerdrum@skogogslandskap.no

Responses to this article, comments are invited and should be submitted within three months of the publication of the article. If accepted for publication, they will be published in the chapter headed 'Discussions' and hyperlinked to the article.