This study focused on how the concentration of volatile oils in Scots Pine needles varied in relation to the age of the trees, the age of the needles and their location within the canopy. Study material were pine needles from 15-, 44- and 89-year-old pine stands. The mean content of oils increased with the age of trees. The averaged oil content in needles was: 0.46% in the 15-year-old stand, 0.55% in the 44-year-old and 0.61% in the 89-year-old stands. The mean content of volatile oils decreased with the age of the needles. 1-year-old needles contained the highest concentration of volatile oils (0.56%), and the 3-year-old needles contained the least (0.48%). In 15-year-old stands the oil content in needles increased linearly with their height in the canopy. In 44-year-old (age class IIb) and 89-year-old (age class Va) stands oil content was greater lower in the canopy than in the middle.
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