Back in cowboy times, a westbound wagon train was lost and low on food. No other humans had been seen for days. Then the pioneers saw an old Jewish rabbi sitting beneath a tree. "Is there some place ahead where we can get food?" they asked.
"Vell, I tink so", the old man said, "but I wouldn’t go up dat hill und down de udder side. Somevun tole me you’d run into a big bacon tree."
"A bacon tree?" asked the wagon train leader.
"Yah, an bacon tree. Vould I lie? Trust me. I vouldn’t go dere."
The leader goes back and tells his people what the rabbi said.
"So why did he say not to go there?", a person asked.
Other pioneers said, "Oh, you know those Jewish people – they don’t eat bacon."
So the wagon train goes up the hill and down the other side. Suddenly, Indians attack them from everywhere and massacre all except the leader who manages to escape and get back to the old rabbi.
Near dead, the man shouts, "You fool! You sent us to our deaths! We followed your route but there was no bacon tree, just hundreds of Indians who killed everyone but me."
The old Jewish man holds up his hand and says, "Oy, vait a minute." He quickly picks up an English-Yiddish dictionary and begins thumbing through it.
"Oy Gevalt, I made myself such ah big mistake! It wasn’t a bacon tree, it was a ham bush!"