"How many yew logs could you log if you were a yew logger?"
There is nobody that hates you/yew puns more than a yew tree. Whenever a passing human makes one of these puns, the yew tree remembers. They let their hatred form a knot in their trunk. Look closely at the knot and you will see that it bears a striking resemblance to the punning offender's laughing face.
That yew will crush one of its berries which, I am sure you are aware, is toxic to humans, and will daub it onto a twig. When the human passes by later, they will wait for a passing gust and whip the twig across the face. If the yew tree is lucky, it will be a fatal blow.
When the crime scene investigators arrive to find out what happens, the yew tree smirks and says to itself "YEW DID IT".