To research wound-wood formation dynamics in Norway spruce trees (Picea abies (L.) Karst), cambium was wounded with a 1 mm wide pin. During the 2003 growth period (9.5.-26.9.), damage was done at weekly intervals. Anatomic changes were observed on cross sections of wound tissues, and histometric research made with a microscope including a picture analysis system. The formation of wound-wood was analyzed with the help of the Gompertz growth function. Research shows that tracheids in wound-wood have thicker cell walls, smaller lumens, and are shorter than those in normal wood. Uniseriate and biseriate rays also occur in the wound-wood. In callus, withered remnants of cambial cells are present, as well as particular cells in post-cambial growth. Traumatic resin canals are present only in particular cases. In all the studied trees, the increase of wound-wood was bigger than that of normal annual rings. After the regular cambial activity the divisional activity of the Spruce No. 3 was for approximately 4; Spruces Nos.1, 4 and 5 for approximately 3; and the Spruce No 2 for approximately 2 weeks after the regular cambial divisional activity. In the spruce trees from Pokljuka, the average regular cambial divisional activity lasted for 11 weeks, while the average divisional activity of wound cambium for 15. The thickness of the wound-wood in direct closeness of the stitch (2nd measure location) was always smaller than those in the 1st and 3rd measure location. The analysis of the wound-wood growth with the Gompertz growth function shows that the increase of the wound-wood in the 1st and 3rd measure locations in the Spruces Nos. 1, 2, 4 and 5 on average is highest around the day 40; the highest increase of the wound-wood on the 2nd measure location in the Spruces Nos. 1, 2, 4 and 5 on average is highest around the day 53.
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