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Stem quality of Quercus cerris trees from Kosovo for the sawmilling industry

Bajrakatri A., Pimenta R., Pinto T., Miranda I., Knapic S., Nunes L., Pereira H.

Drewno : prace naukowe, doniesienia, komunikaty

2018

vol. 61, nr 201

57--69

Quercus cerris is an important species in the forests of Kosovo with a potential high economic value, although there is little information on the stem quality for the saw-milling industry. This study brings data on wood properties, particularly on heartwood, sapwood and bark development within Q. cerris trees grown in two sites in Kosovo, where mature trees were felled, and discs taken at different stem height levels. The average radial growth rate was 1.21 and 1.76 mm yr-1 for both sites. Heartwood decreased from the tree base upwards with a proportion of 53% and 43% until 5 m of height in the two sites. The radial width of sapwood was higher at the stem base (on average 44 mm) and afterwards approximately constant at 32 mm. The taper was low at an average 3.3 mm m-1 between 3.3 and 7.3 m of height. Bark represented on average 16.4% of the total stem cross-section and contained a substantial proportion of rhytidome (51% of the total bark area proportion at stem base and 41% at 9.3 m). Q. cerris in Kosovo showed good potential as a timber species for the supply of stem wood to the saw-milling industry, allowing good yields of heartwood-only sawn wood components. The bark should also be considered for complementary valorization.

Tree-ring chronology as a source of information on susceptibility of Sitka spruce to climatic conditions of Pomerania (Northern Poland)

Feliksik E., Wilczyński S.

Geochronometria

2008

Vol. 30

79-82

This paper presents results concerning climatic conditions affecting diameter growth of Sitka spruce introduced to Baltic Pomerania (Sławno Forest District). A relatively high homogeneity of tree-ring series permitted to construct on their basis the tree-ring chronology of Sitka spruce. A significant positive correlation was found between radial increments of Sitka spruce and air temperatures of winter and spring months (January-April) and a negative relationship between radial increments and temperature of May. This study also showed a distinctly positive correlation between diameter growth and precipitation in July and November of the previous year, and precipitation in February and in summer season (June-August) of the current year. During years with low precipitation in summer or low temperatures in winter and spring all trees produced narrow tree-rings. The proportion of air temperature and precipitation in variation of radial increment of Sitka spruce, expressed by the coefficient of multiple determination, was 52%.