Where does a tree’s mass come from? Welcome to BFSU: › Forums › Volume One › Learning Progression “B”: Life Science › Lesson B-10. Plant Science I: Basic Plant Structure and Reproduction › Where does a tree’s mass come from? This topic has 0 replies, 1 voice, and was last updated 2 years, 5 months ago by Bernard Nebel. Viewing 0 reply threads Author Posts April 10, 2021 at 6:28 pm #8679 Bernard NebelKeymaster After watching the following video, your kids will know something that most people don’t. The bulk of a tree’s mass, and the mass of all other plants, comes from carbon dioxide absorbed from the air. Author Posts Viewing 0 reply threads You must be logged in to reply to this topic.