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Frangula alnus Mill.
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Alder Buckthorn
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Rhamnaceae
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Transversal section |
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Semi-ring- to diffuse-porous. Pores rather widely spaced, solitary or in short radial multiples and small clusters. Growth ring boundaries rather distinct, marked above all by abrupt transition in pore size. Sparse apotracheal parenchchyma. |
         
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Radial section |
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Simple perforation plates. Fine spiral thickenings. Heterogeneous rays, marginal cells generally in one row of square and upright cells. Apertures of the ray-vessel pits slightly enlarged. Libriform fibres present, fibre-tracheids absent. |
   
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Tangential section |
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Rays generally bi- and triseriate. Axially oval ray cells. Average ray height: 10 to 20 (to 30) cells. |
   
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Key characters |
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Semi-ring-porous. Simple perforation plates. Spiral thickenings. Rays slightly heterogeneous. |
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