A man joins the French Foreign Legion...

So this man joins the French Foreign Legion and is being briefed in the middle of the desert by his superior. After the run down of his new life, protocols and procedures, he can't help notice that there's very little to do in the way of "entertainment".
Approaching the commander, he asks discreetly "I notice that there's a lack of women around here. How do we.. errrm.. what do we do if we have an 'urge'?"
"Ah, I'm glad you asked me, soldier." the commander responds. "You see that tree over there?" he points yonder. "Well, whenever you have that 'urge' just put your old fellow inside the tree and enjoy."
"Hmmmm" the soldier responds dubiously.
Weeks pass and the solider is starting to feel the seminal vessles start to get a little plump, if you know what I mean. He decides to head towards the tree that the commander told him about. Sure enough, there was a hole in the tree at the right height. Reluctantly, he unzips.... puts his privates in... and to his extreme delight feels a warm pair of lips encircle his member and bring him to an earth shattering climax.
Completely content with this new-found pastime, he continues to frequent the tree until one day he goes there, inserts his member but.. nothing!
Disturbed, he goes to the commander's tent to find out what's going on. "Sir, I just tried out the tree but nothing is happening!"
"Oh!" said the commander. "We forgot to tell you.... it's your turn to sit in the tree."