Show Him your card

A cocky Department of Agriculture representative stopped at a
farm and talked with the old farmer; "I need to inspect your farm."
The old farmer said, "You better not go in that field."
The Agriculture representative said in a "wise" tone, "I have
the authority of the U. S. Government with me. See this card, I am
allowed to go wherever I wish on agricultural land."
So the old farmer went about his farm chores.
Later, the farmer  heard loud screams and saw the Department of
Agriculture rep running for  the fence; close behind was the farmer's
prize bull. The bull was  madder than a nest full of hornets, and the
bull was gaining at every step.
"Help," the rep shouted to the farmer, "what should I do?" he
screamed helplessly.
The old farmer, hooking his thumbs in his overalls, called out:
"Show him your card!"