background and textured surface bark of tree.

arbor arboreal arborous background bark brown cambial cambium coarse coniferous cracks crevices curved deciduous fibrous fissures gnarled grain growth hardwood heartwood knots layer layers natural organic pattern peeling periderm phloem ridges rings rough roughness sapwood scars sheath softwood striations surface texture textured timber tree trunk vascular weathered woodgrain xylem