The existing trunk and limbs get larger by slowly putting on new growth just beneath the tree's bark. The bark itself has an outer component that we can see and an inner component that is alive and continually growing.
The outer bark itself is continually changing and being pushed outwardly as new heartwood is being laid down by the inner bark. All this takes place at a slow pace.
The fence staples when first driven into the tree shown here went through the bark and into the heartwood, which held the staples in place. Over the years, new wood inch by inch grew steadily outward around and beyond the staples, eventually burying them and the attached parts of the fence deep beneath the bark.
Stapling fence wires to a living tree is a poorly thought-out practice. Many years later an unsuspecting timber cutter may hit the embedded wires with the teeth of his chain saw. The chain could break, injuring the timber man.
The tree shown here is a chinkapin oak, which is so closely related to the white oak that its wood is valued the same and used for the same purposes as the white oak. The white oak is one of Missouri's most valued trees. Fence wire sticking out of a tree renders it unsafe to be cut for lumber.
Through the Woods is a weekly nature photo column by Aaron Horrell. Find this column at semissourian.com to order a reprint of the photo. Find more work by him at the Painted Wren Gallery.