Buchheim

Are there any corrective measures that I can take? Should I trim much of the tree down since It's quite tall (about 80 feet) and in a residential area?

Something strange is happening to my backyard ash tree. I am looking to build a deck around the base of the tree; however, before I decided to do that I did something foolish and covered the base with dirt and soil. I noticed there strange growths about 2 years later. I removed the dirt and soil and want to move forward with my deck around the tree, but once every week or two I get these strange yellow growths at the bottom. They start small but can grow several inches wide. They are soft but dense. Any idea what this is...what is causing it...and what can be done to ride myself of this? I also noticed there are some small dead white worms at the base of the tree as well. They are about 1/4 of an inch long. Not sure if this is related...what they are...and how to rid myself of those as well. Cheers!