TREE ALTRUISM. “We injured the Douglas fir by pulling its needles off, and by attacking it with western spruce bud worm, and it then sent a lot of carbon in its network into the neighbouring ponderosa pine. “My interpretation was the Douglas fir knew it was dying and wanted to pass its legacy of carbon on to its neighbour, because that would be beneficial for the associated fungi and the community.”
http://www.bbc.com/news/science-environment-34849374