(Level of difficulty **)
Question: How do plants move nutrients around the their body?
Materials you will need:
•Small nail scissors
•An outdoor plant with green leaves
•Locate a tree outside (maple, oak, elm, tulip and many other broad-leaved trees would work) with green flat leaves
•Look at a single green leaf and find a midvein (a thicker stem-like structure in the center of the leaf that divides the leaf in two symmetrical halves)
•Using scissors, carefully cut the midvein close to the stalk without damaging the leaf blade (see pictures)
•Using scissors, carefully make a similar-size cut on a leaf blade of another leaf (see pictures)
•Observe what happens to the damaged leaves over time compared to the untouched leaves on that same tree
Helpful hints and suggestions:
•You may want to label the leaves you cut (for example, by attaching a piece of colored tape or ribbon to the leaf stem (called petiole), so that you can easily identify them on the tree)
•It is a good idea to cut multiple (3-5) leaves, so that you can compare the results across different leaves treated in the same way
•For this experiment instead of a tree you can use a houseplant such as violet, philodendron or another broad-leaved plant, but make sure you ask an adult for permission first!
•Leaves with damaged midvein are unable to move nutrients and water across the leaf and are likely to wilt and die
•Leaves with minor leaf blade damage are usually fine
•Why do you think that leaves with the midvein damage are sicker than the ones with the leaf blade damage?
•Do you think the results of this experiment would be different if you were to collect the leaves and keep them in a glass of water (in other words, if you were to damage the detached leaves)?
•Do you know the type of plant (the species) you did your experiment on?
•Would the outcome of the experiment be different if you used leaves of another type of plant or tree variety?