EXPERIMENT 6

WATER FROM PLANTS - TRANSPIRATION

In a way, transpiration is to plants what perspiration is tous. It’s the process by which a plant draws water from the ground through its roots and allows it to evaporate into the air through its leaves.

Quite a bit of water enters the atmosphere by transpiration. For example, a birch tree can give off as much as 70 gallons of water a day and a single corn plant up to 50 gallons in one season.

To see transpiration in action, take the plastic sheet and form a puffy bag around the most leafy potted plant available. Seal the bag by gathering the plastic at the base of the plant just above the soil and tying it with string. Put the plant in sunlight for a few hours. If the plastic is pressing down on the leaves, rig up some kind of support for the plastic (like maybe a stick pounded into the ground at an angle).