Steward – March 2019

Contents (Click on a title or scroll)

MGANM February Meeting Notes:Chestnut Hypovirulence

The Battle Against Invasive Plants… and the Rewards

What’s in a name?

The Hidden Life of Trees by Peter Wohlleben: A Review

MGANM February Meeting Notes: Chestnut Hypovirulence

by Nancy Denison, AEMG

It was another packed house at the BRNC February 5 for Dr. Carmen Medina Mora speaking on the American Chestnut and Hypo virulence. Dr. Mora is an MSU grad and continues to work in the MSU labs researching and studying Chestnut disease pathology.

The American Chestnut, Castana dentate,  a tall, large canopied tree with edible nuts was once widespread in the eastern US until wooden pallets from China introduced Chestnut blight which spread and began to devastate trees in the early 1900s. Research of European, Japanese and Chinese chestnut trees has offered hope and success in saving/creating a new strain which is much less susceptible to the virus.

MSU is now cloning rather than grafting these crossed trees and allowing the Forest Keeling Nursery in Missouri to grow the rootstock for planting in Michigan exclusively. Nearby Kewadin already has Japanese-European trees in production as does the NW Michigan Horticultural Station. It was interesting to hear that many cherry and apple growers have or are replacing their fruit trees with Chestnuts. Hypo virulence refers to the biological management of disease which researchers have found to be effective in controlling the virus from killing the chestnut tree and actually allowing the tree to heal itself.  

Dr. Mora’s presentation was enlightening and helped this very unaware backyard gardener (me) understand a promising trend for farmers, consumers and tree lovers. Thank you, Dr. Mora!

Garlic Mustard, Alliaria Petiolata
credit: S.Callahan/Photri Images
Photo by Dreamstime, permissions granted for the sole use of MGANM

The Battle Against Invasive Plants… and the Rewards

by Ruth Steele Walker, AEMG

It’s a never-ending story — the battle against invasive species! Each year Scott and I do battle against several plant invasive species on our property.  In spring there is garlic mustard to pull, at any time of the year there is Oriental bittersweet to keep track of (while planning its demise come warmer weather) and in summer there’s the frustration of fighting the Oriental Bittersweet, tree of heaven and autumn olive.   We’re also removing some things that were planted before we got here like periwinkle and lily of the valley, some things our neighbors planted that have spread on to our property and some things that we planted before we knew better.

Given that fighting invasive plants has become an annual ritual, I was excited to attend this month’s Master Gardener Association of Northwest Michigan meeting where Emily Cook of the Northwest Michigan Invasive Species Network (ISN) spoke.

The ISN covers our county, Leelanau, as well as Benzie, Grand Traverse and Manistee counties in Northwest Michigan.  They provide a host of services and work bees to help eradicate invasive plants from our area.  Their website really says it all:

Why bother with getting rid of invasive plants, especially pretty ones or ones that quickly grow and fill in a bare area?  It’s pretty simple.  Native plants feed wildlife, butterflies and the insects that are necessary for pollinating plants – including those plants that produce our food – and feeding the birds and butterflies.  Plants that grow quickly are likely to be aggressive enough to push out the native plants that are so important for keeping our world healthy and thriving.

Emily divided invasive species into four categories:  plants that were mistakes, like purple loosestrife and phragmites, plants that were prized for beauty before their invasive qualities were discovered such as buckthorn, Japanese barberry and baby’s breath;  plants that were a well-meaning oops, including autumn olive which was heavily promoted as a plant of choice in the 1970s and plants that provide food (and were  brought by our ancestors when they immigrated to this area) such as garlic mustard.

One of the great things I learned at Emily’s talk was that ISN keeps a Top 20 list of plants that qualify as invasive species.  This is important for me to know as a Master Gardener because if I’m giving out advice about planting, I need to know which species are problematic and have been identified as specific problems in our area of the country. 

What was disheartening to hear is that half of the plants on the ISN Top 20 list are still being sold for landscaping.  What was heartening to know is that ISN has a group of landscapers who have agreed not to include invasive species in their projects.  The group is called Go Beyond Beauty and identifies landscapers and nurseries that have committed not to use or sell high-threat invasive plants.  So far ISN has signed up eight nurseries on this list and there are 13 landscapers (two of which have nurseries on the list as well) that are committed to avoiding invasive plants. 

Currently ISN’s focus is on four invasive species: (pictured below)

  1. Japanese knotweed, also referred to as Michigan bamboo.  If you find this on your property, Emily says, call ISN.  Do not move it or mow it!!

    japanese knotweed close-up growing in the UK background and texture. Photo by Dreamstime, permissions granted for the sole use of MGANM

  2. Garlic mustard, the focus of annual pulls each spring.  The nice thing here is it makes a great pesto sauce and you can bag and dumpster any part you don’t eat.

    Garlic Mustard, Alliaria Petiolata
    credit: S.Callahan/Photri Images
    Photo by Dreamstime, permissions granted for the sole use of MGANM

  3. Phragmites, which is prevalent along our shorelines in Michigan.

    Phragmites australis flower close to the lake in autumn. Photo by Dreamstime, permissions granted for the sole use of MGANM

  4. Oriental bittersweet, known for its “kudzu effect” in covering trees and anything else in its path.

    Oriental Bittersweet. Photo by Dreamstime, permissions granted for the sole use of MGANM

If you’re on the fence about removing some of the invasive plants on your property check out some native gardens near you and see how beautiful native plants can be while providing a habitat for birds, butterflies and bees. 

Dicentra canadensis, Squirrel corn. Photo by Whitney Miller

What’s in a Name?

by Cheryl A. Gross, AEMG

It is time to begin making plant wish lists for spring!  Scour catalogues and books, think about adding new landscaped beds, refreshing existing landscaped beds, reducing lawn, benefiting pollinators and birds, oh my.  What plants will you choose? Knowing plant origins and names is very important if you want to be an ecological gardener superstar.

The very best plants for ecological support are native plants.  They developed here and have the intricate relationships between soil, climate, and insects that create the web of life.   Why do native plants matter? Insects create the biomass of food for baby birds. Adult birds prefer insects as well, but as adults can also feed on seeds and berries.  Insects are famously picky eaters. Some insects eat ONLY one plant, while a very few are generalists. Pollinators are required to help plants make seeds and fruit and our food.  The highest quality of nectar and pollen available to our pollinators are provided by native plants. For example, dandelions have only 40% of the nutrition of a native spring bloomer.  When visiting a nursery, buy “straight” native varieties. (To learn about which plants are native visit:

So when visiting a nursery, it is best to buy “straight” native varieties.  The question becomes, though, how can you tell if a plant is “straight” and not a “cultivar” or a “nativar”  Well, ALL plants have Latin names. That name is their scientific descriptor. Many also have common names… or “nick names” and can have many of those. Let’s take Dicentra canadensis. It is also commonly called Squirrel Corn, Wild Bleeding Heart, or  Girls, (in relation to Dicentra cucullaria, also called Boys or Dutchman’s Breeches). Therefore, when shopping for plants, you really should know the Latin name.

Plant scientists LOVE messing with plants and creating “new” or altered plants. These are called “cultivars” because they have been “cultivated”. This includes, but is not limited to, different leaf color, different blossom color or size, or different berry size. When cultivating or “messing” with native plants, they sometimes call them “nativars”.  The problem is this: insects have a specific relationship with the native plant and we have no idea how any change will affect that relationship. The argument is that there is no science to prove that it is a problem. So until there is, cultivars of native plants should be considered OK. I don’t buy it. Science HAS gotten as far as to determine that changing a leaf from green to red changes the enzymes and the chewing insect that relies on that leaf is unable to digest it and that bees and other pollinators cannot access the nectar and pollen in double blossoms.

Here is the final tip. Look at the plant tag to learn whether the plant has been cultivated. Those plants generally have a third name in quotes. For example, if you want a Serviceberry, or Amelanchier laevis, it has many varieties, several second Latin names, and many, many common names. If you see a THIRD name in quotes, “Autumn Brilliance” you know it is a cultivar.  Don’t buy it.

Tree huggers, Birch and Maple. Photo by Kathryn Frerichs

The Hidden Life of Trees by Peter Wohlleben: A Review

by Kathryn Frerichs, AEMG

Once in a great while I am astounded by some new, amazing findings in medicine, genetics, botany, etc.  The revelations in Peter Wohlleben’s book The Hidden Life of Trees create one of those times. The works of natural scientists in recent years have revealed the role of mycelium and bacteria in the soil now called the Wood Wide Web.

Teaming with Microbes by Jeff Lowenfels was reviewed in the Real Dirt previously. In it, mycelium is described to extend plant roots and exchange minerals and water for sugars from those roots.  Miles of threads of mycelium exist in a teaspoon of soil. The mycelium belong to the fungi family and the largest living organism on earth is a fungus that covers 2,384 acres and is dated at 2,400 to possibly 8,650 years old.  Plenty to be gobsmacked about with these discoveries. Then comes Wohlleben’s book to take us to that place of wonder and amazement regarding trees.

Wohlleben reveals how to observe that trees can, in fact, detect smell. The thorned acacia trees in Africa have been observed to ward off giraffes by secreting a bad tasting substance in their leaves tanking them from tasty to nasty.  The long-necked herbivores then trot off to a neighboring acacia and depending upon the wind direction, the trees will have already begun secreting that nasty-tasting chemical into their leaves too. The giraffes have figured out that the downwind trees can smell chemicals from neighboring trees and just move upwind to chomp on other unsuspecting trees.  Trees do, by deduction from this example and others examples, have to be able to “smell” or detect the odor the other trees emit. Some critics claim that Wohlleben’s writing becomes anthropomorphic. Whatever you may want to call it, smell or detect, trees are communicating via odor/smell. Man can be very egocentric in thinking that only the human species can ‘smell’.  I think more of us will pay attention to his work with his imaginative approach.

Peter Wohlleben explains how trees communicate through the air and through the Wood Wide Web (WWW).  Saplings that are living on the shaded forest floor are fed by the mother trees through their roots. The saplings can wait in the dark, so to speak, because the mother trees feed them for decades before an opening in the forest canopy provides the light to fuel their growth. Trees feed one another in times of illness too.  They use the WWW, also known as mycelium, to accomplish this feat. After a number of these examples, you begin to realize that a forest is not made up of individual trees but is a type of super organism. The parts are all interconnected and protecting one another. Trees, also, have the ability to detect artificial light at night  Eventually the light stunts their growth. They need to stop photosynthesis at night in order to rest.

A forest of trees operates in concert with one another by regulating their climate.  The leaves, or their solar panels, provide a cooling effect and feed and water the roots every autumn when they are broken down and become soil.   The depth of the soil increases over time. They can withstand wind storms by buffering each other to prevent being toppled over. By fall the trees have made and stored as much sugar as they can so they shed the solar panels to rot and become new soil for the next season.  Also, Mr. Wohlleben tells us that when man comes along to harvest lumber from these magnificent giant-coordinated organisms called forests, they cut down the oldest, largest most mature trees. Our old growth trees are the biggest carbon sequesterers we have. The first trees to be cut down in a forest are the largest ones ‘who’ are the most capable of helping us fend off climate change.  

I highly recommend The Hidden Life of Trees by Peter Wohlleben to Master Gardeners.   Besides being a delightful read, it is informative, teaches us to respect those giants of the forest living in the slow lane, and recognizes that trees are interconnected in ways we have not anticipated.  Communication, sleep, nurturance, and functioning as one organism make for better survival just as Darwin hypothesized.

Enjoy this wonderful book!

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