How do Ulrich and Georg become friends in "The Interlopers"?

Ulrich is out patrolling his land, hoping to find Georg and perhaps catch him in the act of poaching. He and Georg meet and confront one another. Each man threatens the other. They seem poised for a deadly confrontation as both men are armed. But they both hesitate. During these moments of mutual hesitation, a storm hits and lightning strikes a tree, bringing it to the ground. Ulrich and Georg are trapped beneath the tree....

Ulrich is out patrolling his land, hoping to find Georg and perhaps catch him in the act of poaching. He and Georg meet and confront one another. Each man threatens the other. They seem poised for a deadly confrontation as both men are armed. But they both hesitate. During these moments of mutual hesitation, a storm hits and lightning strikes a tree, bringing it to the ground. Ulrich and Georg are trapped beneath the tree. Ulrich warns Georg that he will be sorry when his (Ulrich's) men arrive. Georg argues the same point, that his men are out on this night as well. They are both still threatening murder at this point. 

Neither man could get free of the downed tree. Ulrich concentrates his energy on opening his flask of wine. The wine is invigorating and Ulrich looks at Georg with pity. He offers him some wine. 

“Could you reach this flask if I threw it over to you?” asked Ulrich suddenly. “There is good wine in it, and one may as well be as comfortable as one can. Let us drink, even if tonight one of us dies.” 

Even though Georg refuses to drink with his enemy, Ulrich continues to lose the hateful feelings he has always had toward Georg. He tells Georg that if his men arrive first, that Georg will be freed first and unharmed. Georg pauses, warmed by this generous gesture, and responds that it would cause quite a stir if word got out that they had become friends. Georg concludes that they should become friends. The feud ends as a result of being in a dire situation together. With the wine, it is something like a "last supper," a time when they bond under extreme circumstances.