That 164 pounds of wood, bark, and roots arose from water alone. Growing five different plants in separate containers of 40 pounds of soil each would have provided replication . There were no controls in the original experiment. Having a container of soil with no plant would have looked at problems of leaching of soil from water, and dust accumulation 3. Hard to do, huh.
Some roots break, some soil sticks.
Plant Nutrients Let's look at what nutrients are needed by plants to grow, and where we believe plants obtain these nutrients. Let's think about these nutrients from the standpoint of their physiologic function and their source.