Native Plant Root Systems
The deep root systems of many Wisconsin native plants increase the soil’s capacity
to stabilize soils, reduce water usage, control water runoff and, consequently,
reduce flooding.
Native Plants Have Deep Roots
The roots of a plant play an important role to help the plant grow and thrive. They
anchor the plant in the soil; absorb water and minerals; and store excess food for
future needs underground. We are all familiar with eatable roots like carrots, beets
parsnips and potatoes. What about the roots of native and wild plants? What are
their attributes? Do they provide food and medicine?
The bulk of a prairie grass plant, it turns out, exists out of sight, with anywhere from
8 to 14 feet of roots extending down into the earth. Why should we care? Besides
being impressively large, these hidden root balls accomplish a lot:
Nourishing soil
Increasing bioproductivity
Preventing erosion
One of the really nice things about bringing native plants back into our environments is
that they are already acclimated to our local soils, rainfall and nutrient loads. Garden
soils need little work for native plants to flourish.
How well do you know your roots?
Roots Quiz
Primary Root Tissues
The roots of plants have four regions: (1) a root cap; (2) a zone of division; (3) a zone of elongation;
and (4) a zone of maturation.
The root cap is a cup-shaped group of cells at the tip of the root which protects
the delicate cells behind the cap as it pushes through the soil. The root cap secretes
mucigel, a substance that acts as a lubricant to aid in its movement. The root cap also
plays a role in a plant’s response to gravity. If you were to place a young plant on its side the
stem would grow upward toward the light and the root cap would direct the roots downward.
The root cap firmly drives the roots downward in most plants. So
strong and persistent is this mechanism that roots has been known to break through rock,
concrete and other hard surfaces. Some scientists also believe that the downward direction of
the root may also be that the plant is trying to escape the sun’s radiation.
Above the root cap is the zone of division and above that is the zone of elongation.
Primary Root Zone
of Elongation
The zone of division contains growing and dividing meristematic cells.
As we learned last time the meristem cells are very
important to the design and function of a plant, they hold the DNA of the plant and create new
cells for the expansion of the plant. If something damages the meristem cells the plant will either
die or be deformed.
After each cell division, one daughter cell retains the properties of the meristem cell, while the
other daughter cell (in the zone of elongation) elongates sometimes up to as much as 150 times.
As a result, the root tip is literally pushed through the soil.
In the zone of maturation, cells differentiate and serve such functions as protection,
storage, and conductance. Seen in cross section, the zone of maturation of many roots has an
outer layer (the epidermis), a deeper level (the cortex), and a central region that includes the
conducting vascular tissue.
The root of a plant provides a significant competitive edge to a plant trying to reach light.
The root of a plant such as a tree provides an anchor and base as the tree stretches to the
top of the forest. In general, the deeper the root and wider it’s base, the larger the plant.
We all have experienced the stunting of plant growth when a root has not the right
soil to anchor in. The tilth and depth of the soil is important to healthy roots.
The leaves of a plant act to channel rainfall
and water to the roots which in turn absorbs it and distributes it inside the plant.
The root is also very good at uptaking toxins and heavy metals. This is why plants
are so good and helping to clean up the earth. This process is called bioremediation.
This intense uptake can also make eating roots and plants dangerous to human
health. That is why it is such a good idea to grow your own food or only purchase
organically grown food. For instance potatoes grown in the toxic fields of commercial
chemical farms are very contaminated.
The roots of native plants can be extremely beneficial to human health. First
peoples referred to any part of a plant growing underground as a root. Bulbs,
corms, tubers and rhizomes are often lumped into the family of roots. The term
root crop refers to any edible underground plant structure, but many root crops
are actually stems, such as potato tubers.
Rhizomes are simply underground
stems. They grow horizontally just below the soil’s surface. They will continue
to grow and creep along under the surface with lots and lots of growing points.
Examples of rhizomes would be lilies, irises, and asparagus. A corm looks a lot
like a bulb but is the actual base for the plant stem and has a solid texture. As
the plant grows, the corm shrivels as the nutrients are used up. Essentially the
corm dies, but it does produce new corms right next to or above the dead corm.
If you look closely at the bottom of the corm, rhizome and bulb you will find
true roots.
Native plants require very little maintenance because they have evolved and
adapted natural defenses to local conditions such as drought, nutrient-poor
soil, winter conditions, disease and insects which can be problematic to
non-native species. This means that natives save residents time and money
because they require little or no lawn chemicals and less irrigation than
non-native plants.
Attractive and easy-to-maintain landscaping features can reduce the amount
of runoff from roofs and lawns. Downspouts can be redirected to help irrigators in
gardens — shallow depressions planted with native plants specifically adapted to
wet conditions. Rain gardens are a great way to help runoff soak into the ground.
Another way to improve your property’s ability to absorb runoff is by reducing the
amount of turf grass, and replacing it with larger garden beds which include native
plants.
A typical lawn absorbs only 10% of the amount of storm water
that a natural landscape can absorb.
A typical lawn absorbs only 10% of the amount of storm water that a
natural landscape can absorb. Replacing lawns with drought-tolerant native
grass is another way to improve drainage and reduce runoff. Most turf grasses are
high maintenance, especially during drought conditions, but native buffalo grass is
an effective alternative because it is low maintenance, increases infiltration and is
drought resistant due to its long roots.
Turf grass roots are 1-2 inches long, while
buffalo grass has roots that reach up to 6 feet! When storm water isn’t able to seep
into the ground, it runs off onto lawns, sidewalks, driveways and streets, picking
up pollutants along the way. Storm water runoff eventually finds its way to storm
sewers where it is transported to a nearby stream or lake — untreated.
Common pollutants found in storm water runoff include lawn chemicals, pet waste,
household chemicals, oil, and soaps used for car washing. Even small amounts of
pollution in storm water runoff can add up to a big problem for lakes, streams, rivers,
and even oceans.
Wisconsin Native Grasses
Fertilizer Basics: A Tutorial
Soil Biology
Soil Health
Why Are Earthworms Good For The Garden?