autumn branch branches dy leaf leaves limb limbs outdoors red tree trees cold holiday seasons snow snowing vacation white winter Australian raven bare bare branches blue black carrion eaters corvids corvus coronoides crow garbage collectors lone loud mournful omnivorous perched perching predators raven scavengers shiny black apple appletree blue fruit leafs nature Nyberg sky abstract appearance background bark bumps close-up colors colours cut-branches dry edge edges gray grey grooves layers lines patterned patterns perspectives ridges rough shape shaped shapes strange surface surfaced surfaces texture textured textures timber tree-trunk trunk twisted uneven unusual variations varieties wood ancient gnarled green gruen old olive Sardinia