Structure of suppressed buds and needle traces was investigated in silver fir (Abies alba Mill.), Norway spruce (Picea abies (L.) Karst.) and scots pine (Pinus sylvestris L.) macroscopically and microscopically. 2 trees per species were selected. We measured diameter and height of trees, and height where first suppressed buds and needle traces occurred. Trees were sawen into discs and thereafter samples for preparations dissected. Tissue sections were prepared in all 3 xylotomical planes and thereafter stained with safranin and astra blue. Images were made by the aid of Nikon Eclipse E800 microscope and computer. We found that there exist macroscopic and microscopic differences instructure of suppressed buds and needle traces in silver fir and Norway spruce, whereas differences were absent in Scots pine. Suppressed buds and needle traces in silver fir and Norway spruce and short buds in Scots pine run perpendicular to orientation of growth ring boundaries. The easiest way to distinguish needle traces and suppressed buds in silver fir and Norway spruce is their anatomy. When present in the bark, at the top of suppressed buds are present cells with meristematic character, whereas this tissue is not present in needle traces. Trace of suppressed buds is composed of radially oriented tracheids with thick walls with helical thickenings. This vascular bundle is surrounded by unlignified cells.
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