Friday, March 15, 2013

Getting to the Root of it All

I recently had the privilege of presenting at the Ottawa Herb Society.  The theme for the evening was all things roots.  I talked about root coffees and wild roots as food, and I spent a little bit of time talking about roots in general, from a more botanical perspective.  I'm sharing the handout I prepared, here.  I hope you enjoy it!  Oh and if there any botanists reading this, feel free to correct any of my amateur mistakes.  :)

It’s easy to be overcome by the sensual beauty of brightly coloured flowers, or relax in the shade of dense, lush leaves, but it’s in the roots where magic and mystery happen and the alchemy of life occurs, transmuting one life sustaining substance into another.  Unless we make the effort to observe what goes on beneath the soil, all these processes go unwitnessed by most.

But roots have important and fascinating stories to tell.  Their shape and structure is complex and immense.  Like icebergs, there is often much more below the surface than would appear by looking at what grows above.  The nutrients that roots absorb are relatively fixed and immobile, therefore roots will frequently extend out in branching patterns to expose as much of their surface area to the soil as possible.  Some long ­lived trees have roots that reach down to 100ft deep or more.  If you were to take the total surface area of the roots of some plants, including the root hairs, and stretch them out in straight line, the distance covered would reach thousands of miles long!

Let’s take a look at what is going on underground.

Functions of roots:
  • ­anchor and support plant in soil
  • absorb water and minerals
  • conduct water and nutrients to stem to be transported to rest of plant
  • receptacles for food storage
  • responsible for vegetative reproduction
Root systems divided into two categories:
      1. derived from primary or seed root
  • ­ first root that comes out of seed typical of dicots 
  • ex. tap roots: main root from which smaller branches arise, thick and fleshy, store carbohydrates (starch, inulin) as food 
  • ex. fibrous roots immediately divide into cluster of approx. equal thickness, can be swollen, fleshy, tuberous i.e. day lily
     2. roots that are derived from some other way­- adventitious roots
  • ­ability to sprout roots from parts of plant that are not actual roots (ex. layering)
  • roots that originate from stem, leaves, old woody roots, branches or root that develops from old root organs
  • typical of monocots
  • types of underground stems: 
       rhizome: stem growing more or less horizontally below ground level­ thick and fleshy or woody, bearing scale leaves roots produced from nodes and buds in leaf axils
     tubers: swollen tips of stems, connected to parent by thin roots
     corm: enlarged base of stem, orientated vertically in soil
     bulb: thickened leaves, called scales forming a storage organ

The root­-rhizome structure
Typical of forest plants, this root structure consists of the rhizome, which is the horizontal,underground storage chamber, from which feeder roots grow in a hair­like mass.  Examples of this include goldenseal, Solomon’s seal, blue and black cohosh and bloodroot.

Not all roots exist below ground.  Aerial roots, aerating roots and prop or stilt roots are examples of roots that grow above ground. Some plants are parasitic and their roots adhere to the host.

Roots also develop amazing, mutually beneficial associations with soil bacteria and mycorrhizae (fungi that colonises the host plant’s roots).  In mycorrhizal associations, the fungus absorbs nutrients from the soil and releases them to the plant cells, as well as extending the root’s reach.  Fungi in turn receive certain enzymes that they require to break down and use lignin and cellulose.  These mutually beneficial relationships are of such  importance that some plants are so dependent on the presence of mycorrhizae in the soil, that the absence of the fungi impedes the plant’s ability to survive.

Harvesting Wild Edible and Medicinal Roots
You don’t have to look too far outside your backdoor before running into a wild edible or medicinal root.  Dandelion, burdock, chicory, yellow dock, evening primrose, Queen Anne’s Lace, elecampane, nettle, day lily... I have harvested the roots of all these plants within a short bike ride from my home.  Many of these plants are weedy, non­native and even invasive and can be harvested without too much concern for damaging plant populations.  However you still need to take into account the plant’s ability to reproduce and grow well.

Familiarise yourself with the plants in your region that are rare, endangered or at-risk and harvest with great care or avoid altogether.  Many spring ephemeral, forest plants fall into this category (ramps, spring beauties, blue cohosh...), as they grow very slowly and only for the short period of time in early spring before the trees leaf out.

Remember, when you harvest a root, you are taking the life of that plant.  Learn which plants can regenerate from the root crown (the top of the root, from which the stem arises) or rhizome and replant these whenever possible, as appropriate.

Michigan herbalist jim mcdonald describes an excellent technique for harvesting the roots of Solomon’s seal without killing the plant:

“Find a plant and trace down the stem till you feel the root in the soil. Very often the roots are quite close to the surface, and if this is the case, and there's not a lot of clay to deal with, you can harvest with your fingers ­ if not, hope you've got a small trowel... The front of the root will have the bud of the next year's growth, while the back can reach upwards of a foot behind the stem. Trace back two to three inches from the stem and sever the rear portion of the rhizome with a knife or trowel (or break it with your fingers), and pull that portion up from the ground.  I find that if I run a finger underneath the roots as I'm pulling it up, I can collect it more effectively.  It will be a creamy white color, and appear to have knobby knuckles indicating the previous year's stalks (I've collected plants over 13 years old). Because the growing portion of the plant is never removed from the ground, plants harvested in this manner show no signs of impact or distress, and will continue to grow unimpeded by harvesting.  Very often, new shoots will grow from where the root was cut, which means more above ground plants, more flowers, more berries, and so more seeds. Also, any pieces of the back of the root that break off will likely, as well, continue to grow into new plants.  Collected in this manner, you'll have more plants growing where you harvest than were there when you started, and that is indeed a good feeling.”

Most roots are harvested in the early spring, ideally before the plant begins putting out too much new growth, or in the late fall after a couple of frosts (there are some exceptions to this).  Roots are storage chambers for nutrients the plants require and these nutrients are at their highest amount when the plant is dormant and drawing little energy from the root.  The roots of biennial plants, (those that take two years to complete their life cycle) should be harvested in the fall of the first year after the plant has spent its growing months drawing and storing energy in its roots, or the spring of the second year before the plant takes all that stored energy and puts it into
flowering and going to seed.

As with all wildcrafting, avoid harvesting in contaminated areas and know that roots will often contain the greatest concentration of heavy metals and other pollutants.

Roots can be preserved, prepared and enjoyed in any number of ways.  I love roasting dandelion and chicory roots for a coffee substitute.  I add the dried roots of Queen Anne’s Lace and evening primrose to my winter stews.  Fresh burdock gets thrown into my long simmering bone broths.  Elecampane is decocted and made into a syrup for coughs.  I tincture yellow dock roots to support the liver, aid digestion and stimulate the bowels. I love working with roots!

What are some of your favourite roots and ways to use them?

Wild Roots: A Forager’s Guide to Edible and Medicinal Roots, Tubers, Corms andRhizomes of North America, Doug Elliott
Plant Form: An Illustrated Guide to Flowering Plant Morphology, New Edition,  Adrian D. Bell with Alan Bryan
Solomon’s Seal, jim mcdonald
Images: Wikicommons

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