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Budding botany fun September 24 2020, 0 Comments

Many times, children see plants presented as static objects rather than dynamic, interesting living things. I have a new card set that can help you bring more liveliness and fun to botany. It is called “What Flower Is Growing Here?” The set has close-up photos of buds and on a second card, the flowers that unfold from them. Children look at a bud and see if they can match it to the flower in bloom. There are 16 different species of plants featured, and their study can stimulate bud observations in both spring and fall. You can see the set here. https://big-picture-science.myshopify.com/collections/montessori-botany-materials/products/what-flower-is-growing-here .

There is a sentence or two on the flower card that helps children understand more about the flower. For more advanced children, there is a text card for each plant that gives its classification, more details of its development, and its origin.

Annuals and herbaceous perennials grow most rapidly in spring and summer. They produce their buds and blooms from spring to late summer. Most of them have finished their activities in autumn. Herbaceous plants that are pictured in the “What Flower Is Growing Here?” set include petunias, pansies, poppies, and peonies. Zinnias, hollyhocks, nasturtiums, lilies, and columbines, along with daffodils, daylilies, and the bearded iris, round out the spring and summer bloomers that die back in winter.

In autumn, there are structures to observe in another group of plants, the shrubs and trees. Several woody plants form conspicuous flower buds by autumn and hold them over the winter before they bloom in spring. All of them form leaf buds, and many form flower buds that are hidden in the leaf buds. The woody plants in “What Flower Is Growing Here?” are the rhododendron, flowering dogwood, and star magnolia. All three of these form their flower buds in the late summer or early autumn.  They have flower buds that children can easily see all winter long. Other woody plants that form visible flower buds in autumn include alders (shown below), birches, forsythias, and the silktassel (Garrya).

Considering these two categories of plants, there is some flower bud to be seen almost year round. After children have worked with the “What Flower is Growing Here?” cards, they are primed to find buds on nearby plants. They can even look at weeds with a hand lens and may be able to find tiny flower buds there. Following buds through their development is an important activity that helps children see plants as alive and dynamic.

When children see the buds during the winter, they will be primed to observe the big changes that come in spring. If they keep a watch on annuals and perennials in the spring, they may spot the buds well before bloom time. It is exciting and amazing to see what a large flower emerges from some small buds.

The same sort of excitement can come in spring when the leaf buds start to open. Woody plants form their leaf buds in the previous summer or autumn, and most are covered by bud scales. Giving children an opportunity to observe next year’s leaf buds will prepare them to appreciate the swelling bud scales and leaf emergence in the spring.

Enjoy watching your plants bring forth their buds and flowers.


Learning from weeds July 11 2020, 0 Comments

With our world in such an unusual condition now, I find the plant world a sane and stable refuge. My garden is a stress-reliever in the best of times, and it is a special help to me now. With our unusually cool and moist weather last month (Is anything usual?), the plants have done well. There was a bumper crop of cherries, and my flowers have been blooming enthusiastically since early spring.

The weeds have also done quite well. Weeds are a good source of material for botany lessons, and they are found all over, in city sidewalk cracks as well as gardens. Their adaptations make them very abundant. There are few problems with uprooting them and dissecting them. It is a good thing to learn your local weeds and know some of the lessons they offer.  

First, perhaps I’d better say what I mean by a weed. It is plant that grows where it is not wanted and displaces or damages the plants I want to grow. In my garden, some violets are weeds because they spread all over. The one below is especially weedy.

Weeding is applied leaf shape work. Learning to recognize the local weeds is a great gardening skill for children or adults. First, children have to recognize the leaves of desirable and undesirable plants. It takes time to carefully observe the garden, and it is important to have a guiding adult’s help to learn what to keep and what to uproot.

I don’t mean that children have to give the weed’s leaf shape a formal name. Many leaves can be recognized by overall appearance, and noting the leaf’s traits, such as lobes, teeth, or a particular surface texture, can help one identify the plant. Whether the leaves are opposite, alternate, or whorled around the stem is also an important trait, as is the overall size and shape of the plant.

Weeds helps hone one’s observation skills. One key to being a great weed is to escape detection for as long as possible. If your children want to find weeds to study, they will have to look carefully. The spotted spurge is a champion at hiding. The dark markings on its leaves make it hard to see against the soil, and it is a prostrate plant, one that grows very flat against the soil. The overall look of this plant, its milky white sap, and its leaves are a good way to recognize it. Warn children that the sap is very irritating, which brings up another reason to know your weeds – learn the hazards that children may encounter handling them. They will need gloves if they are pulling or digging spurges.

Every spring, I pull the dozens of little maple seedlings, which I recognize by their toothed, opposite leaves. There isn’t enough room for them to grow where they have sprouted. The oak seedlings from acorns that jays and squirrels planted sprout leaves that may not look like a mature oak (see below). I want to pull the little oaks quickly before they grow deep roots and are harder to remove so I need to look for their young leaves.

Weed roots can provide interesting material for study, particularly if you can extract most of the root system. Here is a blackberry seedling that I pulled from soft soil. I was impressed by the length of its tap root. Note the transition from the stem to the roots. To make sure the weed doesn’t grow back, you have to get all the stem and the upper portion of the roots. If the top of the root remains in the soil, it can grow new shoots.

If you pull up a red-root pigweed, you’ll recognize it. It is a member of the notoriously weedy amaranth family. The plants are capable of making thousands of tiny seeds.

You can make illustrations to help children recognize weeds by photographing the plant or by placing a specimen that you have collected between two acetate sheets and scanning it or photocopying it. The acetate will help keep the scanner or copier clean.

A field guide to weeds is a great help for identifying them. There is the excellent Lone Pine Guide, Weeds of Canada and the Northern United States for those regions. In the Midwest and Rocky Mountain regions of the US, Weeds of the West, published by the University of Wyoming, is very useful. Northwest Weeds by Ronald J. Taylor is a helpful guide for that area of the US. If you are in the western US, the children’s book, Outlaw Weeds of the West by Karen M. Sackett, is a good resource for learning about weeds and their adaptations. If these do not cover your area, look for a local weed guide.    

Have fun getting down in the weeds!


An imaginary tour of nesting boxes for the plant kingdom December 13 2019, 0 Comments

The nesting boxes for the plant kingdom are a classic Montessori material. (They are usually called Chinese boxes, but I don’t like to use that term. They certainly didn’t come from China.) Like many other materials that were created many years ago, this one needs a make-over or at least a reality check to see if it reflects what children will see in their later studies.

Paraphrasing a Chinese proverb, if your nesting/Chinese boxes are based on a two-kingdom classification, and they contain the bacteria and fungi, the best time to change them was before 1980. The second best time is now.

The point of elementary studies isn’t to teach children names and ideas that they are not likely to see again. Maria Montessori said that children who complete her elementary program would have acquired knowledge equal to a high school student of her day. She wasn’t trying to create a separate set of biology terms; she was giving children the mainstream academic knowledge of her day. Continuing to use the terminology and concepts of the traditional lessons without checking to see current academic view leads to problems. Children may have to discard their Montessori lessons and go back to the beginning to learn contemporary biology. “Unlearning” is very hard for people. They tend to cling to the first way they learned something, and they must accept that their version is wrong before they can accept another view.

If there were nesting boxes that reflect the current academic view of the plant kingdom, how would they look? Here are my ideas.

Picture a large, green box that is labeled “Plant Kingdom.” It could have other labels as well as that main one. Possibilities are the more formal Latin Kingdom Plantae, or the more descriptive one, Embryophytes. The latter is the informal scientific name for land plants.

We take the lid off this box and find a small box labeled “Bryophytes, the nonvascular plants” and a much larger one labeled “Tracheophytes, the vascular plants.” Inside the bryophyte box, there are three smaller boxes labeled “hornworts”, “liverworts”, and “mosses.” Should there be a label for the division/phylum of these boxes? There doesn’t have to be. I have an advanced botany textbook that doesn’t use a Linnaean rank name for these branches of plant life. If you want to add the division/phylum names, see Wikipedia. It is generally quite good for plant classification. 

The larger Tracheophyte box contains two boxes, a small one labeled “lycophytes” and a much larger one labeled “euphyllophytes, the true-leaf plants.” The lycophyte box has three small boxes inside, the club mosses, spike mosses, and quillworts. Alternatively, the lycophyte box could list these three lineages on the lid and not separate them. They are best described as orders of the lycophytes.

The euphyllophyte box has two boxes inside, a smaller one labeled “fern clade, the monilophytes” and a larger one labeled “Spermatophytes, the seed plants.” The fern clade box has several smaller boxes. They are labeled: “ophioglossids – whiskferns, alder’s tongue ferns, and grape ferns”; “equisetums – the horsetails and scouring rushes”; and “leptosporangiate ferns or polypod ferns – the true ferns.” If your school is in a tropical climate, you may need to add a fourth box for the marattid ferns. They are huge plants that grow only in the tropics.

The spermatophyte box holds two boxes, the angiosperms or flowering plants, and the gymnosperms, the naked seed plants. The gymnosperm box holds four boxes – the cycads, the ginkgo, the conifers, and the gnetophytes. It is uncertain at present whether the gnetophytes belong in their own separate box or within another of the seed plant boxes. It is clear that they do not belong in the angiosperm box, however.

The angiosperms or flowering plants must have a big box. They make up about 90% of the plant kingdom. There are several boxes inside their box. A couple of very small boxes hold the first branches – the water lilies and the anise tree. Then there is a small box labeled “magnoliids,” a medium box labeled “monocots,” and a large box labeled “eudicots.” Three-quarters of the flowering plants are eudicots; about 22% are monocots.

All this can be imagined, but it will take quite some creativity to make physical containers that can actually hold an image and information about each of these branches of the plant kingdom. The information should include the lineages of the plant. For example: Sunflower lineages – embryophytes, tracheophytes, euphyllophytes, spermatophytes, angiosperms, eudicots. The text should also give some of the defining features – the derived traits – of each group.

If you need the illustrations or more information, see https://big-picture-science.myshopify.com/collections/montessori-botany-materials/products/the-plant-kingdom. This is a pdf of a PowerPoint for teacher education. You can print the images for use in your classroom. It has all the images you need except quillworts. Those lycophytes are rare, and the main reason to include them is that they are the closest relatives to the ancient Lepidodendron trees.

Please let me know if you need help or have questions on plant kingdom nesting boxes. If you want to have another set for the flowering plants, that’s a more involved story. It would be fun to do, however.

Happy plant explorations,

Priscilla


What impressions of plants are we giving? Part 3. Stems and leaves August 12 2019, 0 Comments

When we use the botany impressionistic charts to introduce children to plants, are we giving them correct information and the important ideas for them to know? That is the question I’ve been asking in this series. I’d like to call the charts “An overview of how plants work” or perhaps “Imagine how plants work." In English, the term “impressionistic” can imply that the material is hazy and unclear.

Several of these charts show people doing things to illustrate what the plant accomplishes. For instance, little men are shown anchoring roots like tent stakes. While some of this may help children understand plants, I find the real plant characteristics and real plant structures wonderful and inspiring as they are.

What do the traditional charts say about stems? One chart says that some stems are weak, and so they have to grow some structure to help them climb to reach the sunlight. This one has always driven me nuts. Nature doesn’t make weak organisms; natural selection acts against the poorly adapted. There is a better way to look at stems that climb. They have adaptations that allow them to grow upwards but don’t require them to develop a thick, rigid stem. Some kinds of vines have flexible woody stems. They are called lianas and they include grape vines and cat’s brier (Smilax). Lianas are common in tropical forests, and their stems certainly shouldn’t be called weak, as the photo shows.

The chart on stems that climb could also show children that plants do many things with their stems beyond the usual connecting roots and leaves. Stem adaptations include food storage (kohlrabi, potato) and water storage (cacti, other succulents). Two quite different looking specialized stems help grow new plants. Corms are short, thick stems that store food and propagate the plant (gladiolus, banana).  Without corms, we wouldn’t have bananas to eat because the domestic bananas are seedless. Runners are greatly elongated stems that enable the plant spread its offspring across the ground (strawberries). Thorns are short, pointed stems that discourage herbivores (hawthorn). Climbing roots, twining petioles, twining stems, and tendrils represent many ways that plants can fulfill their need to reach the sunlight.

The traditional botany charts include a depiction of photosynthesis in the leaf. Please make sure that you are giving children accurate ideas about photosynthesis. Hint: If your “chemical factory in the leaf” chart shows carbon monoxide being formed, it is giving false information. Why should we ask children to imagine false ideas when we can give them steps in the real process? The process of photosynthesis has quite a lot of details, and it must be greatly simplified for children, but if we are going to give them an idea of what goes on, it should be a valid framework to which they can add details later.

The “chemical factory in the leaf” should show that sunlight is used to break apart water molecules. It is the chlorophyll molecules that capture the Sun’s energy. The sunshine-requiring “light reactions” produce hydrogen ions and oxygen molecules. (They also produce high energy electrons and energy-rich molecules (ATP), but that is more chemistry than beginners need.) The hydrogen is joined to a carrier molecule, moved to a different area, and combined with small, carbon-containing molecules that have had a carbon dioxide attached.  A series of reactions produces sugar. Most charts simply show the hydrogen and carbon dioxide entering a structure of some sort and sugar coming out. That is likely to be enough information for the beginner.

Check the depiction of carbon dioxide on your charts. It is a linear molecule. There is a carbon in the center with an oxygen on either side. The oxygens are directly opposite one another – 180 degrees apart. It isn’t like water, which is v-shaped.

I’ve seen charts that show the sugars from photosynthesis being combined into starch, which does happen in plants. A little bit of starch is made in the chloroplast, and it acts as fuel during the nighttime. Starch, however, is NOT transported through the plant’s phloem. Starch is too big to go into solution. The transportable product of photosynthesis is the sugar sucrose (table sugar). The sucrose travels to leaves, stems, and roots, where it is converted to starch, which stores the chemical energy until it is needed. Sucrose is made from two 6-carbon sugars, so there is some processing of the product of photosynthesis before it is transported.

And then there is the chart that shows leaves worshiping the Sun. Do we worship the food on our plates? No, although a healthy serving of appreciation for the food that sustains us is a good thing. The real leaf story is so much more interesting. We can help children imagine how a plant positions its leaves and appreciate beautiful leaf arrangements. As for the leaves, they are arranging themselves to get maximum sun but minimum damage. Sunlight comes with heat, and leaves take action to avoid getting cooked. A leaf in the shade may be oriented horizontally. In full sunlight, the same species may turn its leaves on edge to protect them from heat. In deserts, many plants orient their leaves to catch less of the Sun’s hot rays.

I’ve always found much in nature that is inspiring and remarkable, and that’s without turning plants into people. When we learn about a natural phenomenon, there always seems to be more of the story. This alone can be inspiring to children. We can let them know that there is much more to the story of plants and how they work than we show on the botany charts.  


What impressions of plants are we giving? Part 2. Roots do more than we think. July 14 2019, 0 Comments

Last time, I wrote about the Montessori material called “Botany Impressionistic Charts.” I’ve looked at the meaning of the work “impressionistic,” and the only definition that seems to be relevant to the charts is “overview.” If I ever produce a version of this material, I will call it “An Overview of How Plants Work.”

In my previous article, I addressed the needs of plants, including the one so often omitted, the need for oxygen. This time, I’m looking at roots. Well, not literally looking at them other than on the weeds I’ve been pulling, but I’m reading about them.

Roots on the traditional charts are rather simple. They anchor the plant in the soil, take in water, and prevent soil erosion. This makes them seem about as interesting as tent stakes and drinking straws. There is a lot more to roots. I recently acquired a book called The Nature of Plants: an introduction to how plants work. The author, Craig N. Huegel, states “Roots may well be the most important plant organ and the least understood.” 

Roots are a last frontier for botany for good reason. They are hidden in the ground, and any attempt to see them disturbs them. In the past few years, there have been attempts to image root growth with MRI, CAT scans, and optical scanners in a tube that is buried in the ground amid the roots. Botanists are realizing that understanding roots is very important, both for the health of the plant and the planet. The ability of a plant to take up carbon dioxide depends on its roots.

There are some items of misinformation on the traditional “Botany Impressionistic Charts.”

  • Roots grow only to the drip line of the foliage. Wrong! If you have ever weeded a garden or dug up plants, you’ll know this one is a myth. At least in all but the most mature trees, the feeder roots extend about 2-3 times the diameter of the canopy according to Morton Arboretum, Colorado State University Extension, and other reliable sources. The root spread of herbaceous plants varies tremendously depending on species and environment, but I have seen many root maps of herbaceous plants that show roots extending well beyond the diameter of the foliage.
  • As a result of the spread of roots, the leaves of the plant do not direct rainwater within the dripline because the roots end there. In fact, I found only one example of leaves sending rainwater to roots, and that was desert rhubarb from Israel.
  • Roots seek water. This happens, but not like it is usually illustrated. Most of a tree’s roots grow in the top 6-24 inches (15-60 cm) of the soil. These laterals are the primary water absorbers. There aren’t many larger deep roots, and these don’t turn and head off to distant water. Hydrotropism occurs over millimeter distances, not meters. The part of the root that turns is the root cap, which means only the tip end of the root changes course. Botanists describe root foraging, in which roots grow out from the plant all directions and give rise to many small branches when they encounter pockets of water or minerals that they need. This would be a better picture to give children.

Useful concepts illustrated on the charts include:

  • Roots hold the soil. This is certainly an important function of roots. Another chart could go beyond this and show that roots improve the soil as well. They make channels in the soil and excrete substances that cause soil particles to clump. This helps water and oxygen penetrate the soil. They also excrete substances that help the plant solubilize and gather nutrients such as phosphorus and iron. These exudates feed the helpful soil bacteria near the roots as well.
  • Roots grow around obstacles. They seem to feel their way around the obstacle until their path is open.

Here are other important ideas about roots that are not illustrated on most sets of botany impressionistic charts.

  • The first root of young plants grows down and the shoot grows up (gravitropism). (Soon after the primary root forms, the lateral roots grow from it. In most monocots, the primary root is short-lived, and many adventitious roots grow from the base of the stem.)
  • Roots store the extra food that the leaves make. This is easy to see in a root like a carrot or beet, but even slender roots store food.
  • Roots have feeding partnerships with fungi (mycorrhizae) and bacteria. These microbial partners also help defend the root from harmful microorganisms. The majority of plants relies on mycorrhizae and grows poorly or not at all without them. Children need to know about this, the most wide-spread symbiosis on Earth.
  • Roots can be adapted to serve other functions. Examples include prop roots, climbing roots, parasitic roots (haustoria), and pneumatophores.

I encourage you to give children an accurate, exciting view of roots. There is plenty of mystery and discoveries to be made about the root system. Here is another book that can help you, How Plants Work: The science behind the amazing things plant do by Linda Chalker-Scott.

Happy botany studies!

Priscilla


What impressions of plants are we giving? Part 1. The needs of the plant. June 12 2019, 2 Comments

I have been looking at these charts and asking myself what else children today need to know about plants, and whether everything shown on the original charts is still considered valid. 

Moving past zoology and botany April 30 2019, 0 Comments

Normally, I write about elementary or secondary education in my blog. In this one, I’m addressing an issue that starts in early childhood, and it affects the way children view the living world in their later studies.

Traditionally, Montessori life science (biology) was divided into zoology and botany. The divide began when young children sorted pictures into animals vs. plants. This exercise fit well with the two kingdom approach to classifying the living world. I certainly hope that Montessori teachers no longer use two kingdoms. Biologists began moving away from two kingdoms in the mid-1800s, although it took a hundred years and major advances in biochemistry and microscopy to complete the break. We can give children a more useful overview of the living world than simply animals and plants.

It is time to quit thinking of life science as zoology or botany, or structuring our teaching albums (manuals) this way. When we offer only two categories for living things, children miss much of the living world. While young children are not ready for lots of details, they can sort pictures of living things into three categories, the third being “Other living things.” This tells them that there are organisms that are neither plants nor animals, and it keeps the door open for further learning. Mushrooms, lichens, and kelp are examples of macroscopic organisms that fit under the “Other” heading.

I started my work to bring current science concepts and content to teachers over 20 years ago. My first conference workshop was about the Five Kingdom classification. I spent nearly a decade helping teachers move from two kingdoms to five kingdoms. Then I had to switch gears again as expanding knowledge (via DNA and RNA) of the relationships between living things led to new concepts of classification, principally the Tree of Life and phylogenetics. My book, Kingdoms of Life Connected: A Teacher’s Guide to the Tree of Life, has learning activities and resources for exploring all the branches of life and viruses, too.

The microscopic living world is more abstract and harder to observe than plants and animals, but that does not mean that children shouldn’t know about it. They can learn that microorganisms help plants grow, recycle nutrients, and make foods like yogurt and cheese possible. The disease-causing microorganisms are the ones that we experience most directly, and these get the most attention, but children need to understand the vital importance of microorganisms to all ecosystems.

The book, Tiny Creatures, by Nicola Davies and Emily Sutton (2014) is a valuable resource for introducing young children to the microscopic world. These authors have a second book (2017), Many: The Diversity of Life on Earth, which supports a more inclusive view of life. The Invisible ABCs by Rodney P. Anderson (2006) sounds like it would be for early childhood, but it looks better for beginning elementary. This publication from the American Society for Microbiology has accurate information and good images of the organisms. Its breezy style makes this abstract world more interesting.

Moving past botany and zoology also means considering more than biological classification. It means thinking about the ecosystems, environments, and interactions of life, the structures of life, and the evolutionary history of organisms. Elementary children will have a better idea of the importance of microorganisms after they read Ocean Sunlight: How Tiny Plants Feed the Seas by Molly Bang and Penny Chisholm (2012). This book uses the term “plants” for the ocean’s protists that perform photosynthesis, even though many are not on the green algae-plant lineage. More importantly, it shows children the microbial underpinnings of the ocean ecosystem.  

In elementary life science studies, there will be times to focus on the animals or the plants, but children will have a better perspective if they start with an introduction to the whole Tree of Life and learn to use this conceptual framework. As children develop their abstract thinking, they are likely to be interested in exploring all the branches of life. They will need good tools, such as magnifiers and microscopes, to help them observe the protists and prokaryotes. They also need appropriate search terms for finding resources they can read and understand.

I hope you and your children enjoy studying the greater living world.

Priscilla


What goes on a plant kingdom chart? December 27 2018, 0 Comments

Like its counterpart, the animal kingdom chart, all Montessori elementary classrooms need a plant kingdom chart. A current version of this chart will have the same elements as a traditional one, but the groups will not have the same labels or arrangement as they have had in decades past. DNA studies and phylogenetic systematics have changed the look of the plant kingdom, and our charts need to reflect this. It is hard to find a solid consensus among botanists on the “right” names, but that is no excuse for giving names that we know are obsolete.

I’ve listed my recommendations for contents of a current plant kingdom chart below. The names that I think are most important are in boldface type. The other names may also be useful. Ask yourself, “Will elementary children be able to use this name to find information that they can read and understand?” If you do a search using the name, do you find information that you can use and understand? If not, consider dropping the more technical name and using the common name for the lineage, the one I emphasize below. The terms on charts for children should be useful for understanding the diversity of life AND for finding further information.

Plant Kingdom (land plants, embryophytes)

Bryophytes (nonvascular plants)

                Liverworts (Phylum Marchantiophyta)

                Mosses (Phylum Bryophyta)

 Hornworts (Phylum Anthoceratophyta)

Vascular Plants or Tracheophytes

                Lycophytes or club mosses and relatives (Phylum Lycophyta)

                Euphyllophytes, the “true-leaf” plants

                       Fern clade or Monilophytes (Class Polypodiopsida)

                                  Whisk ferns and relatives

                                   Equisetums or horsetails

                                   Ferns or leptosporangiate ferns or true ferns

                       Seed plants or Spermatophytes

                                    Gymnosperms

                                                   Cycads (Phylum Cycadophyta)

                                                   Ginkgo (Phylum Ginkgophyta)

                                                   Gnetophytes (Phylum Gnetophyta)

       Conifers (Phylum Pinophyta)

                                     Angiosperms or flowering plants (Phylum Magnoliophyta)

                                                                Basal angiosperms

                                                                Magnoliids

                                                                Monocots

                                                                Eudicots

                                                               

For a beginner’s chart, I start the plant kingdom with the land plants, the embryophytes. It is acceptable to add the green algae because they are closely related to embryophytes, but it is clearer if children learn about land plants first, and then add their relatives. Advanced students are ready for a chart of the Viridiplantae (green plants), which includes the green algae lineages and the land plants. It is important for children to understand that land plants and green algae share a common ancestor.

Don’t feel bad about leaving off phylum/division names. While the animal kingdom phyla have been rearranged by DNA studies, they have kept their names. Plant kingdom phyla or divisions, whichever you wish to call them, aren’t as useful anymore. In fact, I have a widely-used, advanced textbook for plant systematics that uses no phylum/division names at all. Instead, it simply uses names with no ranks for the major lineages, such as lycophytes, euphyllophytes, seed plants, and angiosperms. It still uses orders, families, genera, and species, the Linnaean ranks that botanists continue to use for plants.  

There has been a big change that centers on the ferns. An older scheme had four phyla, Psilophyta, Lycophyta, Sphenophyta, and Pterophyta or Pteridophyta. These groups, often called “ferns and fern allies,” were considered more or less equal, but now we know that the lycophytes are a separate lineage from the other three. The fern clade, now considered by some to be a phylum, has three groups once considered separate phyla – the whisk ferns, horsetails, and the true ferns.

I see no reason to put notably out-of-date information on a plant kingdom chart. I especially encourage you to remove any images that are no longer considered plants. If you still have a mushroom on your plant kingdom chart, children are going to associate fungi with plants, even if you tell them that we know now that fungi are closely related to the animal kingdom and not at all close to plants. The visual impression that a chart gives to children is powerful, and it is important to get it as close to current as we can.

Change seems to come slowly in the general knowledge of plant systematics. I did an Internet search for plant kingdom charts and classification, and I found an amazing range of information from very old to current. Some websites even use the terms “cryptogams” and “phanerogams,” which came into use about 1860. Botanists haven’t used them in academic publications for at least 40 years. It is not that they are “wrong,” but they describe a superficial view that botanists had over a century ago. Our knowledge has grown, and there are better ways of expressing the differences among plant groups.

The flowering plants are currently divided into several lineages. I listed the main ones above, basal angiosperms, magnoliids, monocots, and eudicots. Botanists no longer use only the monocot and dicot subgroups, although these are still common in field guides and older publications. The flowering plants make up about 90% of the plant kingdom, and their orders have been defined in the last two or three decades using DNA studies. They deserve their own chart of orders and families.

My plant kingdom chart from my Tree of Life shows the lineages and their relationships. The plant kingdom chart from InPrint for Children gives children more practice with the categories.    

Here are some quick ways to check the information on a plant kingdom chart for your classroom. If the chart shows a row of evenly spaced boxes, it isn’t giving children all the information they need. Bryophytes need to be grouped together and somehow spaced apart from the tracheophytes. Lycophytes should be separated from other spore-producing plants. If the club mosses, whisk ferns, true ferns, and horsetails are all grouped together and perhaps called “fern allies” or “pteridophytes,” that’s obsolete. There should be something to show that the club mosses are a different lineage from the three branches of the fern clade, and if possible, that ferns are more closely related to seed plants. If the term “dicots” or “dicotyledons” appears instead of “eudicots,” then that needs to change. Eudicots (“true dicots”) are the old dicots minus the magnoliids and the basal lineages such as water lilies.

The same criteria for illustrations on a kingdom chart apply to animals and plants. Can you see the important structural features that enable children to recognize the lineage? For example, can you see a fern’s fiddleheads or its sori? Can you see the sporophytes of the bryophyte lineages? Sporophytes need to be visible and described in the text. The reproductive structures and foliage of the gymnosperms help children tell the difference between those lineages. Flower illustrations should clearly show stamens and pistils. Consider showing a fruit as well because fruits are unique to the flowering plants.

In the text for the chart, give children a range of examples whenever this is possible. Children, like much of our society, are less likely to be familiar with plants than they are with animals. They may be surprised to learn that grasses, maples, and oak trees are flowering plants.

Enjoy opening children’s eyes to the diversity of plants! For more information about the plant kingdom and its members, see my book, Kingdoms of Life Connected.


Help with studies of flowering plant families June 01 2017, 1 Comment

For many years, I have promoted the idea of structuring botany around the flowering plant families. It’s a practical way of addressing the diversity of the angiosperms, and it is knowledge that works in many places and at many levels. For instance, organic gardeners need to know the families of vegetables so that they can do the proper crop rotation and fertilizing. Plant identification is much easier if one can determine the family. Flowers in the same family share certain features, so it is quite possible to recognize the family even if you have never seen that species before.

To help you with your botany studies, I’ve just revised and expanded my PowerPoint slides on flowering plant families. This file is a pdf that can be printed to make letter-sized posters of 20 flowering plant families. The slides include text that describes the features of the flowers, and they show photos of family members. To round out this material, I’ve added a representative photo of 48 other families or subfamilies from all branches of the angiosperms. 

Perhaps you would like to do a Tree of Life diagram for the flowering plants. There is a good one in the book, Botanicum by Katie Scott and Kathy Willis. It is part of the Welcome to the Museum series from Big Picture Press (no relation to Big Picture Science), and it was published in 2016. The branches are correct on the diagram (pages 2 and 3), but they have just one example for each branch, and the orders are not stated. The example represents a whole order, which leaves out a lot. For example, the rose order, Rosales, is represented by a mulberry leaf. Mulberries and figs belong to family Moraceae, which is in the rose order, along with rose, elm, buckthorn, hemp, and nettle families. On the other hand, the diagram fits on two pages. It have to be much larger to be more comprehensive. All-in-all, the book is delightful and will provide lots of fun browsing. You will have to tell children that the page on fungi is a holdover from earlier definitions of botany.

The photos of families from my newly revised Flowering Plant Families Slides can be used to create a Tree of Life that has many orders. It gives a broader look at the families than its predecessor, and it is still centered on the families of North America. There are over 400 families of angiosperms worldwide. You don’t need to worry about being anywhere near comprehensive when you introduce children to flower families. Select the main ones for which you have examples from your school landscape, in areas near the school, or as cut flowers. If you or your children want to see the full list, go to the Wikipedia article on APG IV system (Angiosperm Phylogeny Group IV).   

I’m not the only one that advocates structuring botany studies around flowering plant families. Thomas Elpel has written a highly successful book called Botany in a Day: The Pattern Method of Plant Identification. It is further described as “An Herbal Field Guide to Plant Families of North America.”  This book is in its sixth edition. It has color drawings as well as black and white ones, and these could be useful in classrooms. I have not recommended placing this book in the elementary classroom, however, because it includes many food and medicinal uses for wild plants. I do not want to encourage children to eat wild plants or use them as medicine.

Botany in a Day is available from Mountain Press Publishing in Missoula, Montana, which also carries Elpel’s flower family book for children, Shanleya’s Quest. This book is a great one for elementary classrooms, and I strongly recommend it.

Enjoy exploring and identifying the flowers!


Plant surprises in the desert February 17 2017, 0 Comments

In January, I visited Tucson, Arizona and enjoyed exploring the Sonoran Desert. The plants there show many adaptations to the heat and dryness. The cacti and palo verde trees are what I expected. What surprised me is that plants I thought would need much more moisture are also able to survive in that climate.

There had been rain before my visit, enough that several hiking trails were impassable because normally dry creeks were flowing. As usual, if you want life, just add water. The plants that need moisture to reproduce, the spore-bearing plants, came out of hiding and were thriving. I saw a number of different ferns, but those weren’t a big surprise. I had seen ferns growing from cracks in lava flows before. The key for ferns seems to be finding a moisture-conserving crack on the shady side of a rock outcrop.

The spike mosses, genus Selaginella, were fluffed out and green. One of their common names is resurrection plant, so you can image how they look when they are dry. Spike mosses are not true mosses. They are members of the club moss lineage aka the lycophytes. One Sonoran species, Selaginella rupicola, is called rock-loving spike moss.  There were hillsides with many spike mosses protruding from cracks between rocks.

The mosses were looking very green and active. They are known for their ability to dry out and wait for water. They formed their green carpets out on more open ground and in sheltered rock overhangs. It was in one of the latter habitats that I found the big surprise. There were liverworts growing with the mosses.

Liverworts are the plants that have leaf pores that are always open. I think of liverworts as growing in habitats that have abundant moisture, not just isolated periods of wet weather. It is true that the liverworts in Oregon’s Willamette Valley survive the summer drought, but the humidity is never as low nor the temperatures as high as in the Sonoran Desert. The Sonoran liverworts are small, thalloid ones, much smaller than the ones native to western Oregon. They have the right appearance for a liverwort. They look like a flat leaf growing right on the ground, and they branch into two equal parts, which gives them a “Y” shape. They must have special adaptations and be very tough and resilient to live the desert.

Plants offer surprises in all habitats, not just the desert. You just have to take the time to look.