Libriform Fibers

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Libriform Fibers

 

greatly elongated wood cells with narrowed ends that make for wood’s durability and hardness.

The walls of libriform cells are lignified, with occasional oblique pores. In hardwoods (oak, ash), the walls are greatly thickened; this is less true in softwoods (linden, poplar). In some species (maple, elder), the cell walls are thin, holding live protoplast for long periods and containing nutrients (fats, starches). Sometimes, in their early stages of formation, libriform cells are divided by thin transverse septa that retain their living contents and nutrients for long periods (septal libriform). Libriform fibers developed evolutionarily from tracheids during the process of specialization of wood cells.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
According to Table 3-3 in that reference, sapwood water percentages are higher in conifers than in angiosperms, probably because at the time of harvesting, tracheids in conifer woods retain water, whereas in angiosperm woods, vessels empty and fibrous tissue (libriform fibers mostly) is less likely to contain water.
The secondary xylem consists of vessels, thin-walled ray cells and axial parenchyma, and occasional patches of libriform fibers, which are narrower than the vessels.
9b-d), a tank tree, libriform fibers occur singly or in small groups, which form tangential bands (Fig.
11b), some of the libriform fibers are wider and thinner-walled (and thereby probably qualify as water-storage cells, whereas others (darker) are narrower and thicker-walled.
Implicit in the concepts of Bailey (1944) and the tabular data on bordered pits by Metcalfe & Chalk (1950, xlv) is the idea that the tracheid is the primitive (plesiomorphic) type of imperforate tracheary element in angiosperms, and that it has evolved, in'evcrsibly, into fiber-tracheids in various clades, followed by libriform fibers. Libriform fibers are often thought to be dead at maturity, but in fact, when liquid-preserved materials are studied, they prove to have living contents in an appreciable number of genera.
Wood background of stems composed of thin-walled wide libriform fibers (Fig.
ruspoliana Engl, with wide bands of wide water-storing libriform fibers rather than wide bands of axial parenchyma.
Stem background tissue consists of a preponderance of libriform fibers, with variable amounts of earlywood axial parenchyma in the wet season.
These cells have been reported to be libriform fibers, but SEM study reveals small borders (Fig.
Libriform fibers as well as vessels are storied in Peritoma (= Isomeris), which is a shrub with sufficient secondary xylem accumulation to show storying.
Monomorphic libriform fibers are present in most species.
27b), or an entirely fibrous background consisting of libriform fibers may be present, as in most of the woody Brassicaceae studied by Carlquist (1971).