Where do trees get their mass?

   Trees are some of the biggest organisms on the planet, but where do they get that matter to grow?

Now, I think it's intuitive to believe that the tree gets most of its mass from the soil because you can see those roots digging into the soil and they  must be taking something out of there and I mean a tree looks like dirt and it feels solid like dirt but it's not.

     In the early 1600 a scientist named  Johann Baptist Van Helmholt  tried to figure out where the mass  of a tree was coming from.  So he got a pot of soil and very carefully  measured the amount of soil in there.

     Then he planted the tree and took care of it for five years making sure that no soil left or was added to his pot.  At the end of this experiment he was weighted the tree to find that it was 72 kilograms but the massive soil had only decreased by about 60 grams.  This was pretty strong evidence that the mass of the tree does not come from the soil.

     Of course Johann Baptist Van Helmholt did conclude that the tree was made entirely of  water.  Now while  that's not correct at least he was on the right track realizing that the matter of a tree doesn't come out of the soil.

  Ok the mass of  the tree is not from soil and most people say it is from the sunshine, meanwhile that it is not correct actually.

    

  The answer is air, so as it turns out trees are mostly made out of air, out of the carbon dioxide that they take in.  What's interesting is that  we breathe out carbon dioxide  and water (sweat and urine) that's how we lose mass but it's the exact same substance that trees breathe in to gain mass.  So if you can imagine a closed system where it's just you and a tree.  You would breathe out that carbon dioxide and water the tree would take it in.  So you would get smaller while the tree is getting bigger  and in a sense you're becoming  the tree.