abstract appearance backgrounds bare bark brown bumps close-up colors colours cracked cracks dead dry edge edges gnarled gray grey grooves layers lines moss mottled patterns peeling ridges rough shades of colour shapes smooth strips Stump sunlight surface surfaces texture textured textures tree Tree Stump tree trunk trunk uneven variations wallpaper wood break broken cement circles crack decay hollow paving stone tile whole Acer background fissure groove nature sycamore bricks building firm solid strength walls fissures hard natural oak Quercus rugged crevice diamond palm pattern Sardinia cut-branches eyes grain knots knotted lumber patterned perspectives radial-lines shape shaped surfaced timber tree-trunk unusual varieties coconut ridge ringed natural pattern natural texture organic organic texture palm tree striped tree texture