What is the tree mean in the book?

During a nighttime thunderstorm, Cole again sights the Spirit Bear fifty feet away during a flash of lightning. In an instant, the bear disappears, but Cole fears that he will return to kill him. The storm continued to rage without the presence of the bear, and trees are split in two by lightning. The chapter ends with Cole realizing that the tree with the birds have been struck down by lightning, and he shows this first sign of compassion.