I've been fascinated with these 'growths' on our trees for years. They truly are bizarre. According to treestrees.com they could be a Robustus Conk. Well, robust for sure, but conk I don't know - I'll take their word for it. It mentions that affected trees would have numerous woodpecker holes and are, well, rotting. I have a love/hate relationship with these aspens. They are beautiful, interesting, and old. Homes for hundreds of creatures, but also . . . they are approximately 90' tall. I've seen them come down in strong winds, you should hear the thump. I don't want to tempt fate here, and even though we 'manage' them there are a few that are still just a bit too close to our house. It's a dilemma, the beauty and wonder of nature, versus the safety of us humans . . . hmmm lets just say it's an ongoing concern.
