Ulmus woodii

Name

Ulmus woodii

Rank

Species

Generic Name

[Genus] Ulmus

Authors (Pub.)

Wheeler E. A. Manchester S. R.  

Publication

Review of the wood anatomy of extant Ulmaceae as context for new reports of late Eocene Ulmus woods [2007/12]

Journal

Bulletin of Geosciences

Volume

82

Issue

4

Page number

338

Year

2007

Fossil Status

stems (wood)

Stratigraphy

Priabonian

Strat. comment

36.21 ± 0.26MA; lower part of the John Day Formation

Location

near Post, Oregon, USA

Paleoregion

America (North)

Data for Holotypus

Repository

Florida Museum of Natural History, Gainesville, USA

Repository Number

UF 24544

Num

fig. 4 E-H

Pub.

Review of the wood anatomy of extant Ulmaceae as context for new reports of late Eocene Ulmus woods [2007/12]

Diagnosis

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 strand. Fibers non-septate, pits not obvious, thick-walled; narrow elements with crowded alternate pits (likely vascular tracheids). 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 storied. Spiral thickenings not observed.