Two years ago I trimmed our overgrown bay tree with a bow saw. There was one
nice straight off-cut around four feet long and three inches diameter. This
"post" was left bone-dry in the garage for six months then I sharpened one
end and hammered it into a hole and screwed the name plate for out house to
it. Today - a year and a half after bashing it into the hole, the post has
started putting out shoots of new growth!!! I'm gob smacked!

Is it likely to have rooted?

David.