1. Where do plants come from?
Do Now:
If you had to guess, during which century do you think this man lived?
Where do plants come from?

2. Van Helmont’s Experiments
Back in the good old 1600’s, Van Helmont’s tree experiment was cutting-edge.
He found the mass of soil in a pot before and after letting a potted willow tree grow for 5 years.

3. Van Helmont’s Conclusion
Van Helmont found that the mass of soil did not change significantly. He concluded the mass of the tree must come from water, which is the only substance he added to the container.
What do you think of that conclusion?

4. Replicating a Classic
You will be replicating Van Helmont’s classic experiment today.
Instead of a willow tree, you will use miniature pea plants, so instead of 5 years, we’ll only have to wait 3-4 weeks.
Even poly has updated equipment compared to 1630!

5. A different kind of Lab
This lab report will be different from others we have done, owing to its simplicity.
You will work in a group, but EACH OF YOU WILL COMPLETE A LAB REPORT
This report will be low-key: just complete the handout.
The trick is being organized enough not to lose it during the 3-4 weeks the plants will be growing.