Ulmus woodii Wheeler, Manchester Bull. Geosci., 82(4): 338. 31 Dec 2007
- Ulmus woodii
- Generic Name
- [Genus] Ulmus
- Authors (Pub.)
- Wheeler E. A.
Manchester S. R.
- Review of the wood anatomy of extant Ulmaceae as context for new reports of late Eocene Ulmus woods [2007/12]
- Bulletin of Geosciences
- Page number
- Fossil Status
- stems (wood)
- Strat. comment
- 36.21 ± 0.26MA; lower part of the John Day Formation
- near Post, Oregon, USA
- America (North)
Data for Holotypus
- Florida Museum of Natural History, Gainesville, USA
- Repository Number
- UF 24544
- Growth rings distinct.
Semi-ring porous. Vessels solitary (rounded in outline)
and in radial multiples of 2–3 in earlywood, closely spaced,
earlywood zone broad, more than 2–3 earlywood vessels
deep, with a gradual transition to latewood; latewood vessels
in radial multiples and occasional clusters, diagonal arrangement
at time tending to wavy tangential bands, tangential
arrangement more obvious in wider growth rings.
Mean tangential diameter of earlywood vessels 116
(21)–125 (21), range 60–160 μm. Perforations exclusively
simple; intervessel pits crowded alternate, polygonal in
outline, with included apertures. Vessel-ray parenchyma
pits similar in size to intervessel pits, but with reduced borders.
Vessel elements 274 (35)–332 (26) μm long. Thinwalled
tyloses present, widely spaced.
Axial parenchyma paratracheal, intermixed with vessel
elements and vascular tracheids, usually 4 cells per
Fibers non-septate, pits not obvious, thick-walled; narrow
elements with crowded alternate pits (likely vascular
Rays mostly 3–5 seriate, uniseriates not common;
homocellular, composed of procumbent cells. Multiseriate
ray height averages 402 (120)–667 (214), range
320–1200 μm, 5–7 per mm.
Solitary prismatic crystals in chambered axial parenchyma
strands, up to 12 chambers.
Storied structure: narrow vessel elements / vascular tracheids,
and axial parenchyma strands tending to be locally
Spiral thickenings not observed.