We researched the contents of the extractives in living and dead knots of Scots pines in the area of Brdo near Kranj. Using a Soxhlet apparatus extractor we extracted hydrophobic (lipophilic) components with cyclohexane, and then the hydrophilic components with acetone/water compound. We assessed the contents of the extractives gravimetrically. The contents of lipophilic as well as hydrophilic extractives in knots varied considerably in a single tree and among trees when compared. The portion of the lipophilic extractives was considerably higher in dead knots in trees No. 1, 3, 4 and 6, whereas in No. 2 and 5 the difference was negligible. The portion of the hydrophilic extractives was higher in dead knots in No. 1, 5 and 6, but was higher in living knots in No. 2, 3 and 4. In average the portion of the lipophilic extractive was the highest in living knots in No. 2 and was the lowest in the living knots in No. 3. The highest average portion of the hydrophilic extractives was found in the dead knots in No. 6 and the lowest in the dead knots of No. 2. The average portion of lipophilic and hydrophilic extractives among all the examined trees was found to be the highest in dead knots.
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