Leaf Color Experiment

 

Today's Snack: Chop up some leftover ham or chicken. Add shredded cheddar or mozzarella cheese, and a small blob of mayonnaise if you like it. Stir with some salt and pepper. Now plop a heaping tablespoon full onto a leaf of lettuce. Tuck in the two sides, roll it up, and eat! It's a snack! It's a sandwich! It's a salad! It's . . . oh, LEAF me alone! But not completely alone: drink a glass of fruit juice to go with.

 

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Supplies:

 

You need 1½  to 2½ hours for this experiment

 

Two or three green leaves from two or three different trese

 

Two or three leaves from different trees that have already changed color

 

Access to the Internet for tree identification, if necessary

 

Paper coffee filters | scissors

 

One small glass jar per leaf (baby food jars are perfect) and matching lid,

so you'll probably need 4-6 jars

 

A blank address label or masking tape, and a marking pen

 

Rubbing alcohol

 

Plastic knife or spoon

 

A big shallow pan

 

Access to hot tap water

 

Clock, stopwatch or kitchen timer

 

Masking tape | 4 - 6  blank pieces of paper

 

 

Let's learn a little bit about the color that is "hiding" inside each leaf on a tree, with this experiment. You need to do this in autumn, when the leaves are changing color, but there are still some that are still green. You can do this in one large group, or divide into smaller groups, depending on your supplies.

 

Put one leaf next to each empty jar. You'll need a separate jar for each leaf.

 

Label each jar with the label or masking tape. With the marking pen, write the name of the tree that the leaf came from (maple, river birch, oak, etc.). If you don't know, and have access to the Internet, look online at a tree identification website, such as this 4-H one from Virginia:

 

 

http://www.fw.vt.edu/dendro/forsite/key/intro.htm

 

 

Also put on the label what color the leaf is - green, red, orange, yellow, purple, etc.

 

With the scissors, cut as many half-inch strips of coffee filters as you have jars. If you have six leaves and six jars, you will need six half-inch strips of coffee filters. They will be five or six inches long.

 

On one end of each coffee filter strip, write what color the leaf is, as you did before on the jar label - green, red, orange, yellow, purple, etc.

 

Save these strips for later. Be sure to keep them dry.

 

Now tear and crush each leaf into little bitty pieces into the bottom of its jar. Make the pieces as small as you can. Don't spill! Don't mix up the pieces! Do this one leaf and one jar at a time.

 

Pour enough rubbing alcohol into each jar to cover the bits of leaf. Using the plastic knife or spoon, carefully grind and smash the bits of leaf inside the jar so that they're practically powder and dissolved in the rubbing alcohol. This is called "pulverizing," or grinding something into dust.

 

Put the lid on each jar loosely - don't screw it on very tight, because you want a little air to come and go.

 

Fill a large shallow pan with one inch of very hot tap water.

 

Carefully place the jars in the water.

 

Leave the pan next to the sink on the counter or someplace where it's close to the water supply.

 

Let the jars sit for 30 minutes or more. They should turn dark, or even black. The darker the color gets, the better.

 

Every five minutes, shake and jiggle each jar, and check the water temperature in the pan.

 

If it's not very hot, you can quickly but carefully take the jars out, dump out the lukewarm water, put the jars back in the pan, and refill it with very hot water.

 

After 30 minutes, take the lids off. Plunge one end of the labeled coffee filter strip into the alcohol solution in the jar. You should put the coffee filter strip marked "green" into a jar that had a green leaf, for example.

 

Fold over the dry tip of the filter that's sticking out of the jar, and tape it to the outside of the jar.

 

Now let 30 minutes to two hours pass, and watch the colors divide and creep up the filter.

 

When you think you've gotten as much "color creep" as you're going to get, take each filter out of the jar. Carefully tape the dry end on another piece of paper. Keep these separate, and let them dry out. Don't let colors drip on other filters!

 

Once dry, analyze - or study - the patterns you see.

 

Did the two or three green leaves produce the same color patterns? Why or why not?

 

Did the red leaf produce a pattern that is more similar to the yellow one, or a green one? Why would that be?

 

Which leaf had the most hidden colors? Why do you think?

 

Which leaf had the least hidden colors? Why?