The idea here is of a sort of forest monster that hates non-plant life forms. It obviously reminds of treants and the trees outside the shire, but it also reminds me of a Krynoid. Either way, I like it.

zdsdead's lore ran thus:

Stormbranch could not remember, Where, and when he was born. In his mind, he just was, and had always been, here in Arncrow Forest. An elf creature, had once told him that he was born of the magic of a powerful sorcerer Lord, a millennium before. If that was true, Stormbranch did not know for sure. What he was sure of was the humans had now burned, and cut most of his home to the ground. He had killed and driven off, The loggers and Lumberjacks, but now from the edge of what was left of his forest, he could see an army of humans approaching his home, with spears and fire. Tears of sap welled in his eyes, as he realized he would lose his home to these locusts, these humans. He was overcome with rage. They would pay dearly, and with blood....

We may want to tweak it a bit, but the core is sound.