Before their surprising reconciliation, Ulrich and Georg make one main threat to each other whilst they are trapped underneath the tree that has effectively prevented them from killing each other in the way that they would like to. Let us remind ourselves of the context. Both characters find themselves with their limbs wedged firmly under the fallen tree. Ulrich is able to move his arms to access his flask, but apart from that their movement is limited. They have been reduced to a position of complete helplessness thanks to the violent intervention of nature. Thus it is that the threats they make concern what will happen when their men find them. Note what Ulrich says to Georg:
"I'm caught in my own forest land," retorted Ulrich. "When my men come to release us, you willl wish, perhaps, that you were in a better plight than caught poaching on a neighbour's land, shame on you."
Georg in return threatens Ulrich with what will happen when his men arrive first, and taunts him with how easy it would be for them to leave him, dead, underneath the tree. Thus the threats that each character makes involve what could happen if their men were to arrive at the scene first, and the murder that could be so easily and blamelessly committed in such a situation.