These seem to be the common ones on-line:
This puny guys applies for a job as a lumberjack. "Sorry, says the head lumberjack, eyeing the man up and down, “You’re just too small.”
“Give me a chance to show you what I can do,” the guy pleads. “You won’t regret it.”
“Okay,” says the boss. “See that giant oak over there? Let’s see if you can chop it down.” Half an hour later, the mighty oak is felled, amazing the boss. “Where’d you learn to cut trees like that?” he asks.
“The Sahara Forest.”
“You mean the Sahara Desert ?”
“Sure, if that’s what they call it now.”
A blonde travels to Canada to seek her fortune as a lumberjack. She meets a foreman of a logging organization who offers to give her a job.
“Now, I hope you realize we expect you to cut down at least 100 trees a day,” the foreman told her.
The blonde woman didn’t see this as a problem, so she went out with the Chainsaw and did her best. She came back drenched in sweat.
“Geez lady, how many trees did you cut down?” asked the foreman.
“6” she replied.
“What!? You have to do better than that. Get up earlier tomorrow!”
So she did. Out she went with the chainsaw, she came back that night
exhausted.
“How many this time?” asked the foreman. “12” she said. The foreman says, “That does it. I’m coming out there with you tomorrow morning!”
The next morning, the foreman reaches the first tree and says, “This is how to cut down trees really quickly.” He pulls the rope on the chainsaw and it gives off a loud BRRRRRRUUUMMM. He notices the blonde is looking at him frantically, so he asks her what’s wrong.
And she replies, “What the hell is that noise?”