A pictograph of someone who has climbed on a tree gripping the trunk between his legs and is feeling around with his left hand for something under the roof.
It looks like he lost the key to his house and must have hidden the spare one in there. Usually you'd leave your spare key under a potted plant right on your porch, but that's just as good as leaving your door wide open, so he must have not liked that and came up with a better idea.