This is an easy to do classroom science project, with a minimum of materials and expense.

You will, however need a microscope, and some other items to allow the class to participate.

One nice bouquet of flowers will be more than enough for the class.

A Good Bouquet

It is important to know the types of flowers in the bouquet, as the exercise is about identification. The best way to do this is to purchase the flowers from a florist, and be absolutely sure to write down the name of each type of flower and memorize the flower’s appearance. Not every bouquet has a good selection of flowers for gathering pollen, so be sure to choose the right selection. The bouquet on the below is pretty, but NOT very good for pollen selection.

Pretty, but not the best for pollen samples

Daisies provide very nice pollen samples, however they must be mature, and pollinating. Look for flowers, like the one below, which has large anthers, and produces lots of pollen. And be sure to tell the florist to leave the anthers on. Many times they remove these, because the pollen stains clothing. Be careful, and tell your students to be careful, not to get pollen on their clothing.

Alstromeria aurantica, heavy with pollen

You can also buy flowers in the floral section of the supermarket for less money, if you are careful to read the labels and make absolutely sure you can identify the flowers you are buying. Tulips are a good choice, because they are obviously tulips, and they also have plenty of pollen on big anthers. Alstromeria, and Lillies are good choices. Daisies tend to look alike, but there are different species, and it’s important to know what kind of daisy you have. Try to find a floral section of a supermarket that has a knowledgeable person assigned to that department. Below you can see tulips with anthers loaded with pollen.

Tulips, with anthers full of pollen

To start, you will need about 20 slides and 25 coverglasses (also called coverslips). Allow a few extra coverglasses, as these break easily. It is possible to obtain plastic coverglasses as well, and these are safer, but not as high a quality as a glass coverslip. And be sure to have a few more slides than you have students participating. You can purchase slides and coverslips from The Microscope Store

Slides, coverslips, toothpicks, clear nail polish, paper plates

Use self adhesive file folder labels to label the slides. You can cut the folder labels into sections, and they are perfect for making permanent slide labels.

You will need toothpicks as well, to maneuver the coverglass around on the slide.

In addition, you will need slide mountant, and in a classroom environment, a simple bottle of “Hard As Nails” clear nail polish will work fine. It is a definite advantage to have the small bottle with a brush, and a fairly rapid dry time. This mountant is also rather inexpensive compared to professional slide mounting adhesives (like Cytoseal 60).

Model and hobby cement or glue dries crystal clear

You can also use the glue sold in hobby shops that comes in a little squeeze bottle with a long applicator. This cement is excellent for slides, and allows a very precise drop to be positioned on the slide from a needle-like applicator.

When you are ready to start the project, you must give the students some safety instructions. Slides are made of glass, and break easily. I recommend that they place their slide on a paper plate, and leave it there. Students should write their names on their plates.

Approach each student, and paint a swipe of clear nail polish in the center of the slide. The nail polish will immediately start to dry. This is okay, as it will be tacky enough to capture the pollen.

The tulip on the below right is perfect for this activity. You can see how the anthers are loaded with pollen. After you have painted a bit of polish on the slide, immediately hand the student the flower, and let him/her tap the flower so the anthers are over the slide. Plenty of pollen will fall, and it will be more than enough for microscopic examination. Don’t over do it. Leave some pollen for every one.

Tulip - tap it over the slide

While waiting for the polish to dry, have the student focus on writing a small label with the name of the flower, student initials, and date.

As you walk around the room, you can tell the students about The Language of Flowers. There is a book by the same name, written by Margaret Pickston. For just about every flower, and for many plants and fruits, there is a special meaning, and in olden days people would communicate to each other using flowers. A guest in someone’s home finding the American Starwort in her room would know that this meant welcome to a stranger. Wild grapes mean charity. Heath means solitude. The book is a dictionary, listing hundreds of flowers or plants and their secret meanings.  See Amazon link below if you’d like a copy of this book.

Language Of Flowers - secret meanings to flowers

Next, the hard part. You will need to sit down for this. For each student’s slide you must do the following. Set the nail polish bottle down on the paper plate. Unscrew the top, and be ready to lift the brush out, and lit one drip of nail polish fall back in the bottle.

Now hold a single coverglass in one hand, by the edges. Hold it near the slide, but not over the slide. Hold the coverglass over the paper plate, but not over the slide. Smoothly lift the brush out of the bottle, and let a drip fall back in the bottle. Immediately hold the brush over the cover glass, and let another drip fall right in the center of the coverglass. Hold steady. Place the brush back in the bottle.

Now flip the cover glass over, and the drip should hang from the bottom of it for a second. Set it on top of the pollen on the slide, and perhaps center it a little with a toothpick.

The pollen is mounted. Since each student should have his or her name on the paper plate, you could let the slides on paper plates dry overnight. If this is done early in the day, the slides will be dry by the afternoon.

Now you can examine each slide under the microscope, and even take digital pictures by putting the camera up to the eyepiece, and making sure the camera’s flash mode is OFF. If the flash activates, the picture will not come out.

Below picture shows Alstromeria (Lily)  pollen lit from underneath. This is called Brightfield lighting.  Even a modest microscope will give you this type of image.

Alstromeria pollen

Have the students do drawings of the pollen grains as they see them under the microscope. This is a great way to really train the memory as to what the features of the pollen look like. Drawing is a skill that all students should work to develop. Learning to draw is not difficult. One begins as a toddler, by coloring within the lines, then in pre-school by tracing, then copying. Then students should eventually try drawing freehand from a picture or model, and then drawing from the imagination. What better way to reinforce this process than in the context of drawing from the microscope image? This is an artistic expression without fear, as each student is observing and interpreting a unique specimen in every case. By comparing the collection of drawings, not in terms of good or bad, but to define what the pollen looks like by a consensus of drawings, each student makes a contribution to the whole interpretation.

Often the best lighting is achieved by using an LED flashlight positioned above the slide, and no light used from below. This type of lighting is called Incident lighting. You will get a black background, and the pollen in its natural color, however the shape of the pollen is altered by the cement. Therefore, it is best is to take a photo of the pollen unmounted, that is dry, no cement, just sprinkled on top of the slide. This really shows the pollen as it looks in nature.

Pyrethrum magnified 25 x

When the season is right, try to get some sunflowers.  These are fun to grow yourself, then collect the pollen, and afterwards, harvest the seeds.

There is plenty of pollen in this sunflower

Below, you can see the natural look of Sunflower pollen, with lighting from above, unmounted, and just sprinkled on a slide. For the purpose of this activity, however, you must permanently mount the pollen with cement.

Sunflower pollen - magnification 25x

More pictures can be seen on my website:

http://tardigrade.us/pollen/

It would be nice if after the slide preparation, you could leave the flowers in a vase for a few days, for all to enjoy. The students will have seen them on a microscopic level, yet must appreciate their outward beauty with the same fascination they had when looking at the pollen for the first time.

And it’s important to point this out. No matter how we analyze something, or learn practical things, like pollen causes allergies, or bees carry pollen so flowers can reproduce while the bees make honey, we must appreciate the beauty of a flower too.

The beauty of flowers

Its silent presence speaks to us, reminds us of the beauty of stillness, without judgment, without the mental chatter of the mind. Can everyone in the class be silent for a few moments, take a deep breath, and just appreciate the beauty of these flowers? Can the students just allow themselves to look at the flowers without any thought at all, just to see them as they are?

Perhaps the earliest joy experienced on this planet was when early man beheld a field of flowers, or bent down to enjoy their fragrance. Perhaps the first gift ever given a woman by a man was a bouquet of wild flowers. Could we not guess that woman’s first adornment was a flower?

The next time you see a flower, try to see it as if you are looking at it for the first time, with childlike wonder.

Stop and smell the flowers

My cat seems to be able to do this all the time, as she stops to smell the flowers.

See my other articles at:

http://www.xomba.com/user/mwshaw