Diamondeye wrote:
Arathain Kelvar wrote:
DE - it doesn't need to be pure water, nor was obtaining pure water difficult in 1649. I doubt he bothered, as he did not need to.
He didn't? Then the mass of the soil should have changed, yes?
Quote:
Fertilizer adds specific nutrients. Less than 4% of the mass of the tree.
I'm finding all this very difficult to buy from the standpoint of Conservation of Matter.
If a particular tree weighs, say, 1 ton, that's 80 pounds of stuff other than carbon and water, not 2 ounces.
Using the example, the change in mass was 164 lbs - 4% of that is 6.6 lbs.
That's not much. Trees can gain some nutrients from the air, and the tree may have been nutrient poor. Consider also that there's a lot of error in this type of experiment; trees shed mass, for example (into the soil), and so on. The point, without getting too worked up over the specific numbers, is that the change in soil mass was extremely small compared to the mass gain of the tree. The overwhelming majority of a tree's mass comes from the air.
I can buy that. However, 6.6 pounds is still a hell of a lot more than 2 ounces - around 50 times more. That means his watering needed to add around 6 pounds to the soil in order to account for that much of the tree's net gain in mass.