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Damage caused by harvester head feed rollers to alder, pine and spruce

100%

Karaszewski Z. , Łacka A. , Mederski P. S. , Noskowiak A. , Bembenek M.

Drewno : prace naukowe, doniesienia, komunikaty

2016

tom vol. 59, nr 197

77--88

The harvester head causes damage to the bark and wood on the lateral surface of the processed assortment. The severity of the damage may be influenced by the construction of the harvester head and tree species characteristics, such as bark thickness and wood hardness. The study aimed to recognise and compare damage caused to hardwood and softwood. Wood from alder, pine and spruce was harvested using a Valmet 911.4 harvester equipped with a 360.2 head. Logs measuring 2.40 and 2.50 m in length were used in this study. The depth of the damage caused by the feed roller spikes was measured using a digital caliper. Comparison of these defects across the three species revealed that as bark thickness increased so the depth of damage to the timber decreased. Damage to the alder logs in the form of dents and gouged timber fibres was shallow: from 1.7 to 3.7 mm, and significantly less than that to the softwood logs: in the pine from 5.9 to 7.8 mm, and in the spruce from 3.9 to 5.6 mm. Damage to the middle and top logs for each species was similar and depth varied little along the entire length of the processed assortment. Such damage only slightly lowered the quality of the alder wood, which had the thickest bark. Application of the Valmet 911.4 harvester caused less damage to the alder wood than to the softwood (pine and spruce).

Oak bark share at different heights of stem

100%

Karaszewski Z. , Bembenek M. , Giefing D. F. , Szczepanska Alvarez A. , Maderski P. S.

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

2014

tom 86

Statistical characteristics of double bark thickness at breast height based on pine (Pinus sylvestris L.), larch (Larix decidua Mill.) and oak (Quercus robur L.)

80%

Kazmierczak K. , Pazdrowski W. , Szymanski M. , Nawrot M.

Colloquium Biometricum

2009

tom 39

Wstepna dendrometryczna charakterystyka wybranych cech sosny zwyczajnej na proweniencyjnej powierzchni doswiadczalnej w Polanach k. Grybowa

70%

Orzel S. , Sabor J.

Acta Agraria et Silvestria. Series Silvestris

1994

tom 32

37-44

W pracy stwierdzono istotny wpływ pochodzenia sosny na wysokość drzew oraz grubość odkładanej kory. Badania nie wykazały natomiast istotnego wpływu pochodzenia na wielkość pierśnicy i miąższość strzał bez kory w badanej populacji sosen.

The purpose of this study was to present the biometric description od 16 native proveniences of 28-year-old Pinus silvestris growing in the V-th block of the provenience experiment area in Polany near Grybów. Such dendrometrie characters of trees as d.b.h. (d), height (A), bark thickness at the height of 1.3 m (k), and volume of stems without bark (v) were taken into account. It was concluded that the variability of characters under investigations did not differ basically from that reported in literature for forest stands of similar age (tub 1). The provenience was significantly important in case to height and bark thickness (tab. 2, fig, 1 and 2), and on the other hand had no effect on d.b.h. and volume of stems without bark. The pine originating from Gubin was characterized by lowest values of all characters studied, while the highest values were reached by the following proveniences: Karsko, Dłużek, Rozpuda and Lipowa (tab. 1, fig. 1). The existence of significant interproveniencial differences in pine bark thickness may play an important diagnostic role in the distinguishing the individual proveniences. The determination of the variability of this character may be of significant importance in the silvicultural appraisal оf Scotch pine populations in the mountain areas.

Zmienność wybranych cech morfologicznej budowy drzew daglezji zielonej (Pseudotsuga menziesii var. viridis Franco) w Polsce

60%

Wasik R. , Michalec K.

Acta Agraria et Silvestria. Series Silvestris

2010

tom 48

This paper presents the results of investigation into the variability of selected features of morphological structure of Douglas fir trees in Poland. The research was carried out in 28 Douglas fir stands, which were at least 80 years old. The mean values of studied features amounted: diameter at breast height — 54.8 cm, height — 32.4 m, bark thickness — 3.9 cm, crown length — 13.6 m, relative crown length — 41.6% and crown width — 5.4 m. The significant variability of studied features was stated, especially large diversity bark thickness and crown width was revealed. Four regions were distinguished in Poland. These regions were characterized by some distinction of the studied features.