Trees may be larger than they appear
How to make a tree double its size, instantly: approach it carrying a chainsaw with intent.
What looked perfectly manageable while you paced around it with your hands in your pockets will, during the interim while you walk back to the garage, find the saw, gas it up, and walk back out into the yard, will have swollen to California redwood proportions. The trunk will creak ominously at you while you stand there feeling somewhat less manly than you did a few minutes ago.
This is why the dead tree in our front yard has been standing there for more than a year.
It finally fell down last week. So there.