Well if you fall from the tree or scrape yourself on the tree than yes or if the tree falls on you than yes that would hurt. But if you and the tree do not make contact than there is no way of getting hurt.
No. Its the same as blood. You can give a pint and not be "hurt". You make more, so does the tree.
no
Tree's cannot feel " pain " or " hurt " but it would technically damage and possibly kill the tree due to water lose.
no
yes
they are woody and spikey and hurt if you run into them
no the tree will be fine
yes it does :(
no, they won't normally hurt a tree
In very rare cases,only if you hurt them they might bite even then it does not hurt because their teeth are so small.
It wont hurt you however if it grows a face and starts moving, it will break your axe if you don't stop chopping.
Well, technically anything you do to injure the tree will hurt it, but over the long haul of the trees life, the fact that one nail is hammered into its bark should not endanger the tree. It has more important things that will hurt it -- like lack of water, sunlight etc. I have cut down many large trees (I worked for Asplundh) and found nails way inside the tree that were hammered in there 50 or 60 years ago and the tree stayed healthy and strong.