|
| Commercial timbers |
Nomenclature etc. JUGLANDACEAE. C. tomentosa (Lam.) Nutt.; C. ovata (Mill.) K.Koch; C. laciniosa (Michx.f.) Loud.; C. glabra (Mill.) Sweet. Trade and local names: mockernut hickory, bullnut hickory, hognut hickory, white heart hickory, true hickory (US), hicorytrae (SE). Not protected under CITES regulations.
Tree. Geographic distribution: North America.
General. Growth ring boundaries distinct. Heartwood basically brown, yellow, white or grey; without streaks. Sapwood colour distinct from heartwood colour. Density 0.66–0.76–0.8 g/cm³.
Vessels. Wood ring porous to semi ring porous. Ring of earlywood vessels uniseriate. Vessels arranged in no specific pattern, in multiples, commonly in short (2–3 vessels) radial rows. Average tangential vessel diameter 180–270–450 µm (90–330 fide WAGENFÜHR). Average number of vessels/mm² 2–11. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 7–10 µm. Vessel-ray pits with distinct borders, different from intervessel pits (but smaller than intervessel pits). Helical thickenings absent. Tyloses present, thinwalled.
Tracheids and fibres. Fibres of medium wall thickness. Average fibre length 920–1300–1700 µm. Fibre pits mainly restricted to radial walls, simple to minutely bordered and distinctly bordered. Fibres non-septate.
Axial parenchyma. Axial parenchyma banded. Bands marginal (or seemingly marginal) or not marginal (or seemingly marginal). Axial parenchyma bands forming a reticulate pattern with rays. Bands fine. Apotracheal axial parenchyma diffuse, or diffuse-in-aggregates (in short tangential lines). Axial parenchyma as strands. Average number of cells per strand: 4–8.
Rays. Rays 15–18 per tangential mm, multiseriate, 2–3 cells wide. Height of large rays commonly 500 to 1000 µm. Rays composed of a single cell type (homocellular), or two or more cell types (heterocellular); homocellular ray cells procumbent. Heterocellular rays with square and upright cells restricted to marginal rows, mostly 1 marginal row of upright or square cells.
Mineral inclusions. Crystals present, prismatic, located in axial parenchyma cells. Crystal-containing axial parenchyma cells not chambered. Number of crystals per cell or chamber one. Crystal containing cells enlarged (idioblasts). Silica not observed.
Physical and chemical tests. Heartwood not fluorescent. Water extract not fluorescent; colour of water extract colourless to brown. Ethanol extract not fluorescent. Colour of ethanol extract colourless to brown. Splinter burns to full ash. Ash white to grey.
Illustrations. • Macroscopic images. transverse (ca. 10x). tangential (natural size). • Transverse section. Carya ovata. • Axial parenchyma. Carya ovata. fine parenchyma bands, primarily in latewood. • Tangential section. Carya ovata. • Radial section. Carya tomentosa.
The interactive key allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting specified attributes, summaries of attributes within groups of taxa, and geographical distribution.
Cite this publication as: ‘Richter, H.G., and Dallwitz, M.J. 2000 onwards. Commercial timbers: descriptions, illustrations, identification, and information retrieval. In English, French, German, Portuguese, and Spanish. Version: 9th April 2019. delta-intkey.com’.
