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First Page

497

Last Page

515

Abstract

Wood and bark of 12 collections of Empetraceae representing three genera containing seven species (one with two subspecies) are analyzed with respect to quantitative and qualitative features. Empetraceae have vessels somewhat angular in transection, with scalariform perforation plates and scalariform to opposite vessel-ray pitting. Imperforate tracheary elements are all tracheids. Axial parenchyma is sparse and not subdivided. Rays are characteristically uniseriate and composed of upright cells (older stems have rays with both upright and procumbent cells). These features ally Empetraceae closely to Ericaceae and Epacridaceae. The narrow vessels, quite numerous per mm2 , denote a high degree of wood xeromorphy; growth rings and tracheid presence also may be indicative of adaptation to drought or physiological drought due to cold. Rays composed of upright cells, nonconversion of the uniseriate rays to multiseriate or heterocellular rays, and decrease in vessel element and tracheid length with age are generally accepted criteria for paedomorphosis in dicotyledonous woods, and these apparently apply to Corema and Empetrum as well as small shrubs similar to them: Cassiope (Ericaceae), Empleuridium (Celastraceae), Myrothamnus (Myrothamnaceae), and Tetratheca (Tremandraceae). Data on bark are presented for all taxa of Empetraceae.

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© 1990 Sherwin Carlquist

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This work is licensed under a Creative Commons Attribution 4.0 License.

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