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As a gardener, I know humans have introduced many invasive species like Dandelions, Japanese Knotweed, and Phragmites, into many of our native North American habitats. I have witnessed it, and to some extent participated (in ignorance) of the problem.

As little as two hundred years ago the forests surrounding the Great Lakes lacked earthworms. The Ice Age and glaciers eliminated the native species, and during the 10,000 years since the last glacier, our trees and plants evolved to live in the wormless local soils. This became a thick layer of duff or the debris of trees and shrubs that lined the forest floor. Duff remains for years, slowly decayed by fungi, but providing a habitat for many Michigan ferns, delicate wildflowers, and small animals like salamanders.

Since settlers first moved into this area, they introduced European earthworms like the red wriggler to encourage composting. Gardeners still think of worms as a desirable asset to their garden’s soil. These worms eat decaying matter, aerate the soil, and leave humus-rich worm casting behind as they burrow. In general, they do good things for garden soil.

In the forests, however, worms eat the duff in as little as two years, lowering the soil’s acidity and making nutrients more available. The plants in our forests survived in the poor fertility and the high acidity of our original native soils. While the introduction of worms won’t necessarily harm the mature trees growing there, the duff’s absence affects the number of seedlings growing in an area. It also makes an advantageous situation for unwanted invasive species that couldn’t have grown in the more acidic original soil.


As this debris layer disappears, so does the habitat for plants like Trillium, Solomon’s Seal, Blue Cohosh, Sweet Cicely, Mayflowers, Wild Ginger, Lady Fern, Bloodroot, Bellwort, and the tiny Goblin Fern which might already be extinct in this area. They adapted to germination and growth in the thick layer of duff that provided them nutrients, moisture, protection from extremes in temperature and predators, and microorganisms like fungi necessary for their survival.

It is also believed the loss of the duff effects the salamander population that fed on insects living in the debris. The salamanders, in turn, provided food for snakes, shrews, thrushes, and screech owls, so the earthworm invasion affects a whole chain of living organisms.

Worms were introduced from dumped fishing bait, on the root-soil clumps of purchased plants, and on the tires of vehicles entering the local forest. The most severe invasions are usually near roads. This is one reason the U.S. Forest Service is restricting logging and road-building in certain forest areas in states around the Great Lakes.


Once the earthworms infest an area, little can be done to remove them without doing more harm to the forest. We know many of the above plants grow in worm-infested soil because we grow them in our gardens, but a study in the Chippewa National Forest in northern Minnesota showed these species do not return to worm-infested forests.

Some ecologists hope the ecosystem of the forest may eventually come to a new balance. In the meantime, don’t spread earthworms into wormless areas, don’t dump worm bait in forested lands, and keep your vehicles on roads and trails. Gardeners in wooded areas need to keep compost piles and worm contaminated soil from contaminating the woodlands. These may seem like small measures, but it was a little thing that started this change.

(Updated. Originally published in the Cadillac News in 2002.


Book coverAn Organic Guide to Growing Vegetables, Berries, and Herbs in Cold Climates

By By John Whitman
University of Minnesota Press
ISBN 978-0-8166-9839-4
February 2017|

FRESH FROM THE GARDEN is a marvelous book. It is a large and comprehensive volume for growing edible food plants only, but discusses edible flower garden plants and other unusual and unexpected edible plants. This book is for gardening in cold areas like mine, and as a long-time gardener, I know this can be difficult.

Part I is devoted to the basics of gardening and growing crops organically. It explains a variety of approaches from growing in containers to creating many types of land gardens. Soil and compost is explained along with how to water and fertilize. Directions for plant seeds is provided, but it also includes other methods of propagation. It explains how to grow crops and how to weed and harvest them. The information goes further to include culinary terms, food storage, and even gives reasons why some people love or hate a particular vegetable. All the tools and products necessary for gardening are listed along with safety tips. Great photos and many easy-to-understand charts supplement the text.

One thing among many I learned was that pH means potential hydrogen. I’ve known what a pH reading was and how it applies to plants, but not what the acronym meant. It’s not only the solid information but also the good advice provided, such as the myth the gardener controls their garden, and many ways exist to achieve a bountiful harvest. Author John Whitman encourages gardeners to use whatever method works best for them.

The most wonderful part of FRESH FROM THE GARDEN is Part II– an extensive listing of all the vegetables, berries and herbs that can be grown in the food garden. Many I have grown, but even more I haven’t. From asparagus to zucchini, every crop is described. The information includes when and where to plant, the plant’s nutritional facts, the varieties available, how to grow it, problems and pests that can occur, and how to harvest and store the crop.

While FRESH FROM THE GARDEN is invaluable for gardeners in cold areas, defined in the book as anywhere the temperature can dip below -20 degrees Fahrenheit, the basic information is relevant anywhere. The extensive list and discussion of crop foods makes this garden book one every gardener will seek out repeatedly, not only when choosing plants to grow for the upcoming season, but also whenever problems or questions occur during growing or harvesting of those crops. For beginning gardeners or experienced gardeners, FRESH FROM THE GARDEN offers effective gardening know-how.

photo of plant's complex societies

Complex societies

Since 2000, scientists, and in particular botanists, have been delving into the sentience of plants. They’ve made some amazing discoveries. Plants are not the insensate lifeforms Homo sapiens has believed for so long.

Most people, in the past and still today, think of plants as living, but sedentary things that just grew and either thrived or didn’t, but which provided humans food, medicine, and clothing. People presumed they lacked the ‘anima’ or movement and cunning of the upper echelon of life forms, animals, of which we humans, with our self-awareness and intelligence, dominate all other creatures and even the planet Earth. At least, again, that is what many think. We are now learning that we can change the Earth, but it isn’t always a smart thing to do, and that plants and ‘lower’ lifeforms might not be so much lower, and even in someways, smarter.

In reading a 2015 publication, Brilliant Green, The Surprising History and Science of Plant Intelligence, Ismarty-plants’ve learned philosophers since before Aristotle have wondered and postulated about plants, and whether they have souls, a sign of intelligence. Even Darwin and his son had views on plant intelligence which seemed to have been largely ignored. The authors of this book go on to describe plants’ ability to communicate, to remember, and to feel, see, hear, taste, and touch.

Programs like Nature on PBS are also creating shows like “What Plants Talk About,” (also known as “Smarty Plants” in Canada) which cover the discoveries about the ignored nature of plants. On Ted Talks, Stefano Mancuso  speaks on “The roots of plant intelligence,” and The New Yorker’s video “Do Bean Plants Show Intelligence,” based on the research of Michael Pollen, show scientists’ perceptions of plants are changing. Many videos are available on line to show the extraordinary discoveries about plant behaviors.

I’m sure most readers know that plants can survive without humans, but most ‘higher’ life forms cannot survive without plants and their ability to use sunlight, carbon dioxide from the air, and minerals found in the soil to produce sugars and other food substances. Depending on the species, they can live one season or for thousands of years. They clean air, water, and the soil that humans pollute. As mentioned, they take carbon dioxide from the air and release oxygen back into the air. What we often don’t know is they live in complex societies both above and below the soil, and when we decimate a forest for wood products, we can also decimate the society of entities that made the forest a healthy and productive ecosystem in the first place.

It is time for humans to stop taking plants, and other life-forms for granted and to use the products and life forms on Earth in a responsible way. Our existence depends on it.

Some gardeners insist on the necessity to improve their garden soil. They till in organic matter, peat moss, vermiculite, add sand to clay soils, lime and fertilize trying to achieve perfect soil for gardening. While this works very well, it is just that, work, and often very expensive. There is another argument that claims disturbing the soil causes more harm than good; these gardeners promote growing plants that naturally grow in the soil type found in their yard. It is certainly less work, and if the plants are adapted to your soil, they grow very nicely. Both are right. The argument is not about soil at all, but about the gardener, time, effort, and cost.

My soil is sand deposited by melting glaciers eons ago. It has fast drainage, so can go dry very fast. I have also gardened on very deep silt soil called Loess or the dusty silt blown off glaciers. It’s similar to clay in that it compacts and makes for poor drainage.

The soil topic comprises entire books, including the geology and science behind the types and how to handle them. However, there are one common sense tip for ordinary gardeners: know the soil type and the pH of the garden bed. A soil test will tell the soil’s composition, its pH, and the amount of NPK (Nitrogen, Phosphorus, Potassium–the components of fertilizer) needed for optimum plant growth.

Soil pH is important to know, indicating if the soil is acid or alkaline. pH 7 is neutral, anything below acid, anything above alkaline. Most low rain fall area soils are alkaline as various mineral salts accumulate and are are not washed by frequent rain, most soils in rainy areas are acidic as the various mineral salts are dissolved and washed away. So what? Some Plants have soil pH preferences, others don’t care. Some plants like blueberries want very acid soil, others like lavender prefer alkaline soils. Very acidic or alkaline soils limit the plants that grow in them. In many cases plant preferences depend on the plant’s original global location.

Other than that, there are very few soils that grow nothing, and few perfect soils that grow everything. The base of good soil or garden loam combines clay, sand, and silt, the three basic sizes of mineral content in a soil. Clay is the smallest and compacts easily into, well, clay bricks, but has greater surface area for holding necessary minerals. Sand is the largest and drains fast, but holds less fertility. Silt is somewhere between the two, created by water sedimentation. It has characteristics of both, and the problems of both. Clay soils hold nutrients and water, but they are slow to dry out, and once dry may crack into rock-hard plates on the soil’s surface. Sand soils hold little moisture or nutrients.

It is also important to know that the mineral content makes up only part of a soil’s content. Fifty to fifty-five percent of soil consists of air, water, decaying plant materials (humus), insects, worms, bacteria, fungi and other living organisms. Plant roots use the air, water, and humus for plant growth as well as the minerals found in the soil. Their pH preference helps them absorb these substances. All the living organisms within the soil help decay plant material and often act in symbiosis with the plant’s roots. I’ve read where there is more life below the soil’s surface than there is living on its surface.

Even if you have amended your soil, you need to know its basic type and how to work it. Three rules of thumb:
1. Never work in a wet clay soil, and don’t walk on a wet lawn growing in clay soil. You drive the air spaces out of the soil. Once compacted, reintegrating air space into clay soils is difficult.
2. Sandy soils need additional water and fertilizer applications.
3. In cases of extremely sandy or clay soils, garden in raised beds formed by mounding good loam on top of the native soil.

If you don’t have inclination for the work involved in soil improvement, grow plants for the soil you have.

Clay soil? Grow Aconitum (delphinium), Anemone, Aruncus (goats beard), Asters, Buxus (boxwood), Camassia, Digitalis (foxglove), Forsythia, Helenium, Hemerocallis (daylily), Ilex (holly), Leucojum (snowflake), Mondarda (bee balm), Myosotis (for-get-me-not), Narcissus, Paeonia, Rudbeckia (coneflowers), Solidago (goldenrod), and Viburnum.

Acid soil? Grow Achillea, Allyssum (gold dust), Artemisia, Echinacea, Eryngium, Gaillardia, Helianthemum, Iberis (candytuft), Lavandula, Lilium, Oenothera (evening primrose), Salvia, Sedum, Sempervivum (houseleek). Look up the plants preferences before you purchase them. If you don’t, invest in one for a trial growing period. If it thrives, grow more.

A good garden book will give you more plants for each type of soil. If a plant requires good drainage it will do well in sand. If it requires rich soil, it might grow better in clay or loam soils. Good drainage and rich soil usually means soils leaning towards sandy with high humus amounts.

Whenever I work the soil–Master Gardener lesson one: gardens are made of soil, not dirt–I think about the science fiction series Dune, which ends with the entire universe of the story existing within the soil of a rose garden.

In some ways this is an accurate image of soil: a different universe full of life. Soil is a living thing containing the minerals of the universe (Another scientific but scifi like connection: Carl Sagan wrote: “We are made of star stuff”), water, air, the detritus of life or humus, and microbial life. And like any living thing, soil can be killed by poison, starvation, suffocation, or drowning. Soil is the skin of the living planet Earth, and like our skin, other life lives on and within it.

Fungi on a pile of bark mulch looking like an alien species invading Earth.

As a gardener, the first thing I learned was respect for the soil, and rightly so, as a great deal of the world’s life is supported by what lives in soil. Only plants can produce their own food, all of us of us eat either plants or other animals to survive. I expect our society might be more peaceful if human bodies could manufacture their own food. Oops! Off topic. (Besides, on reflection, I realize plants are often at war with each other—doesn’t this sound like a scifi tile? War of the Plants.)

How much life is underground? It depends on the soil, its temperature, moisture, air content, mineral makeup, and condition. Within my soil I can see macro life such as worms and insects, even mammals like moles living in the depths, but by far the largest category of life is invisible to the naked eye: microflora and fauna like bacteria, mold, fungi, algae, protozoa and nematodes. If you’re lucky, your soil is full of life, or like me, you continually feed your soil with compost and mulch to make it healthy.

Here’s a fun fact to put this unseen life in perspective. Jeffrey Gordon, a professor at the Washington University in St. Louis School of Medicine has stated that up to ninety percent of the cells in our bodies are non-human cells, from microflora and fauna similar to those found in the soil. So imagine a being as big as the world’s soil mass. What’s more, our lives need that non-human life living in and on us just as much as the soil in your garden does.

So there it is, Frank Herbert, Dune‘s author, was right, there are millions of alien species living on the trillions of mineral planet particles within our soil’s universe. Bet the next time you work the soil, you might hesitate about just what you’re sinking your hands into.

Update: National Geographic has the scope on dirt — #5 Soil is Alive — also some scary information on how humans abuse soil at great risk to themselves.

*This is from one of my older posts on*

Big Bluestem along 3 Mile Road

Big Bluestem along 3 Mile Road

I suspect that many drivers traveling Michigan’s roads this autumn are more attracted by the color of the changing leaves than the weeds along the roadside. Recognition of those ‘weeds,’ however, can change that viewpoint.

For most of the spring and summer, a grass is just a grass, a clump of green blades, mostly needing mowing. Come late August, however, something amazing happens. The native grasses Little Bluestem and Big Bluestem bloom and embellish many of Michigan’s roadsides with their burnished glory. It may look like dead brown grass to many, but a closer study shows an amazing array of color from the yellow to yellow-orange flames of basal grass leaves to the ripening splendor of the slender reddish, glowing amber or pink stalks.

Once, I too thought of these grasses as weeds, and then I learned a little more about these two native grasses. Big Blue Stem (Andropogon gerardii) once covered the prairies from the Ohio River to the foothills of the Rockies. It was the predominant prairie grass covering much of the Mid-West. By late summer the seed stalks often rose to seven feet, or in some locals, even ten feet (those in my fields grow to six feet!). The name came from the lavender-gray seed heads, the slender finger-like shapes of which gives Big Blue another common name, Turkeyfoot.  Red splotches stain the stems, so as the wind whips them, the red and green on the stems seem to blur into blue-gray. For our early settlers, it must have looked like another ocean when late summer winds propelled the tall grasses, which often reached up to 12′, into waves of motion that formed the grass sea. Sometimes I imagine the vast herds of buffalo and antelope living on land covered by this grass or traveling in a wagon where the grass along the trail towers over me. It must have been a remarkable sight.

Big Bluestem Crowned by Maple in October

Now Big Bluestem is known for its superior qualities as forage for cattle, horses, and, to
the hunter’s joy, the Michigan white-tail deer. However, as the settler’s plowed under the prairie grasses in the Mid West and Western states, something else happened: they destroyed roots of the prairie grasses
including the Big Bluestem. Their very deep roots were often deeper than the grass’s
height and had held the soil in place for centuries. When drought hit the prairie, the roots that had acted like anchors for soil and moisture during periodic droughts were gone, and the corn and grain crops planted in place of the grasses, couldn’t hold the soil. The topsoil blew away in great black winds sometimes blowing as far away as New York. This drought resulted in the Dust Bowl, affecting hundreds of thousands of acres of land. John Steinbeck’s novel, The Grapes of Wrath, depicts the sorrow inflicted from this ecological calamity. (See Ken Burn’s THE DUST BOWL preview.)

Rolla, Kansas, Dust Storm 1935 From the U.S. National Archives, NAID 195691

Rolla, Kansas, Dust Storm 1935 From the U.S. National Archives, NAID 195691

Little Bluestem (Schizachyrium scoparium), often grows next to Big Bluestem along the roadside. Even from the car, the difference can be seen. Little Bluestem is shorter than Big Bluestem, usually reaching only three feet in height. While this grass’s leaves are highly prized for their blue-green summer color, in fall they turn pinkish-tan to brilliant orange with fluffy white seeds running up the stem-like tufts of a hair. This feature gives the grass its other common name of Beard Grass. Little Bluestem lacks the great stature of Big Bluestem, but it has a fragile beauty to distinguish it. The frosted pink or pronounced reddish-tan stalks of Little Bluestem dress an autumn field in rare beauty.

Little Bluestem

Little Bluestem

Another of the predominate prairie grasses, Little Bluestem also exists in greatly reduced circumstances, although the pink-red-orange fall coloring has piqued the interest of landscapers and horticulturists which has established it as a ‘garden plant.’ A few plants have even received cultivar names for certain superior qualities, usually summer or autumn color, and are now available in nurseries. For ranchers and farmers, though, like Big Bluestem, Little Bluestem has great
nutritional value for livestock. Maybe they both can make a comeback.

Now that I know and can identify Little Bluestem and Big Bluestem, I look for them in the fall. Like the red-orange of the sugar maple in autumn, they have become an important indicator of the season. The maple adorns the sky, the bluegrasses gild the ground. It is most unfortunate that so many counties and townships mow them down at the peak of their glory.

A Michigan Autumn with Little Bluestem

A Michigan Autumn with Little Bluestem



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