Can Plants Reproduce by Breaking Apart?

Many plants usually reproduce asexually [a- is a prefix meaning "without"]. Strawberries send out 'runners' which are long spindly stems. When these runners touch and remain on the ground long enough, roots develop producing a new plant which is a clone of the parent. When I planted strawberries in my garden (as a grade school student), I tested this by cutting some of the runners after new plants formed, then compared the growth of the cut new plants to the uncut ones [but did not measure them]. Sumac trees and mulberry trees send out underground horizontal stems, then develop roots and a new vertical stem producing a new plant. Often during floods, willow tree branches will break off. These broken branches are then carried down river by the flood waters. When they land on a sandbar or on the riverbank, they develop roots and become new clones of the parent at some distance from the parent. Many ornamental perennials can be dug up and split to make two (or more) new plants which seem to thrive well when replanted.

If the above explanation were true, we ought to be able to duplicate this process as an experiment. For this experiment, I will describe the process for willow cuttings. You may wish to try this with some other plant. I recommend that you try with a number of different plants until you find one which works well for you. You should note that if you do this before attempting it in your classroom, you are the one learning by discovery. There is no good pedogogic reason to deny your students the same oppurtunity to learn. In other words, you can try different plants in your classroom until you and your students find some that work well in your classroom.

You also need to know that there is a product available from stores that sell live plants, usually for landscaping purposes, that is supposed to improve the development of roots on cuttings. The product is usually sold under the trade name Rootone™ either as a liquid or in powder form, complete with instructions on how to use it. This also suggests a new experiment to confirm (or reject) the advertising claim that Rootone™ improves the process of propagating plants from cuttings.

intended for grade 3 (to 6)

Introduction

1. Question: Will broken branches of a plant grow in new plants?
2. Hypothesis: parts broken off a plant can grow into new plants,
   I have observed willow trees on new sandbars created by floods on a river. These willow trees appear to be too old to have grown from seed after the flood.
3. alternate hypothesis: parts broken off a plant should die.
4. State what observable event is expected to occur because the hypothesis is true:
   a branch cut off a willow tree, and 'planted' in water will become new plants.

Materials and Methods

Written just like a recipe, in sufficient detail that anyone should be able to duplicate your experiment.

• Materials: what supplies are needed (be specific), and how much of each.
  • branches cut off a willow tree
  • vases (one for each branch)
• Methods: what do you do with the supplies?
  • fill vases about 3/4 full of water
  • cut bottom end of branch at an angle
  • quickly transfer one cut branch into each vase
• experimental design:
  • experimental group where conditions are met:
    vase with freshly cut branch
  • control group where conditions are not met:
    none

Data

• Record what actually happened,
  and not what you think should have happened.

Depending on the age of your students, this may include descriptions, drawings, numbers and graphs, ...

Conclusions

• based on data presented:
  • "The hypothesis has been proven to be true."
    or
  • "The hypothesis has been proven to be false."

[optional] you may discuss how this changes our concept of how the Universe works? This section could also stand alone as a formal essay as can the introduction.
You nay wish to compare branches in water to branches in water with Rootone™ added per instructions on the Rootone™ bottle.

Works Cited

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