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.
The last few cell rows of libriform wood fibres at the border of the annual rings are more strongly lignified than the weakly lignified libriform wood fibres of the early wood.
Studies carried out by Schwarze et al on some tree species show that parenchyma cells resists degradation by brown rot fungi, whereas the surrounding libriform wood fibres are strongly decayed .
Are libriform, of moderately short length, fine diameter and thick walls.
Are libriform, of medium length, medium diameter and very thin walls.
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).
The most useful application of "specialization" in the Major Trends papers refers to differentiation in the roles of tracheary elements from tracheids which support the plant and conduct water into separate support (fiber-tracheids, libriform fibers) and conductive cells (vessel elements).
The xylem in the cacti referred to by these authors does have "division of labor" in that they bear both vessels and libriform fibers, so this statement cannot represent sense 1, and it is not sense 2 because there is no reference to a linear hierarchy.