Thursday, 13 September 2007
Woodpecker signs: barking?
Many mammals feed on and mark trees: beavers, voles, mice, squirrels, hares, rabbits, deer, even sheep and goats. Generally the marks they leave are easy to separate from those left by woodpeckers, as gnawing and individual tooth marks are left by mammals rather than peck marks. Barking refers to the marks left by deer and elk when they have eaten tree bark. I include it here because such markings can be confused with woodpecker work. Most barking takes place in spring when trees are growing and thus their sap is rising. This of course is also a period of great woodpecker activity. The mammals tear off bark in long strips (usually from bottom up) and leave large incisor marks. In winter bark is tougher and more firmly gripped onto the trunk, so the marks left by deer then are different, with clear lines or furrows left. By contrast woodpecker leave fine peck marks when stripping off bark and the bark is torn off in short sections and from top to bottom.