Are you connected to Earth’s Natural Internet?


Are you connected to Earth’s Natural Internet?

By Bob Dailey

There is a fungus which grows in the soil on and around plant roots that is absolutely essential for plant health. In fact, this fungus is so important that some plant species cannot exist without it. Named mycorrhiza, which literally means “root fungus,” this organism creates a symbiotic relationship with plants. The amazing properties of this root fungus has prompted scientists to call it “Earth’s natural internet.”

If one digs into leaf mold, or into really good soil, tiny white filaments resembling spider webs can be seen spreading through the soil or leaves. This is mycorrhiza. Though deceptively small, a teaspoon of good soil can have eight or nine feet of the tiny strings.

Mycorrhizal fungi create a symbiotic relationship with plant roots, taking in minerals from the soil and delivering it to the plant, in exchange for sugars produced by the plant. Plant biologists have estimated that 95 percent of the plants investigated are either partially or completely dependent on these fungi- a testament to their importance. Orchids, for instance, are so dependent on mycorrhiza that even their seeds cannot germinate without it.

Once attached to plant roots, this fungus sends out tiny threads which extend out much further than the roots can extend.  Though they look like plant roots, these white filaments are what absorb nutrients. Since they have a great deal more range than the plant roots themselves and have significantly more surface area, they are able to find and take in significantly more water and nutrients than the plant roots can. Scientists have also discovered that mycorrhiza can store up nitrogen when it is plentiful, and then release it to the plant when there is a lack of nitrogen in the soil.  These fungi can also store water, which it releases to the plant in times of drought.

Plants that are not aided by these fungi may not be able to take up important nutrients such as phosphate or iron – which can lead to iron chlorosis or other plant deficiencies. Mycorrhiza can also play a protective role for plants in soils with high heavy metal concentrations, such as acidic or contaminated soils. These fungi are also suited for colonization of barren soils.

Soil-borne diseases (such as take-all patch and brown patch) are also serious problems for plants. Unfortunately, many residents are quick to apply fungicides at first signs of take-all or brown patch. While these fungicides will kill the bad fungi, it will also kill the mycorrhiza. A better method may be to inoculate the lawn with organic material that has high concentrations of mycorrhiza.

Studies are showing that plants colonized by mycorrhizal fungi are much more resistant to these and other diseases.  Scientists have also now determined that mycorrhizal fungi can also transport nutrients and water from plant to plant through extensive underground networks.

Operations like tilling can also kill mycorrhiza, although aeration prior to adding organic matter will do relatively little damage to it.  For floral or vegetable gardeners, many experts are recommending “no-till” methods.

Try “No Till” in your vegetable garden


Humans have tilled the earth since they stopped being hunter-gatherers and became farmers. The tradition has been to turn over the earth before planting to get rid of weeds and to make it easier to use fertilizers to plant crops. Mechanical tillers have made things easier, but tilling is still one of a gardener’s most difficult tasks.

However, soil scientists are now realizing that tilling interferes with the complex relationship of the soil and the micro-organisms that keep the soil healthy and productive. Tilling also compacts the soil, brings long-dormant weed seeds to the surface sale and adds to erosion. In fact, poor agricultural practices like tilling helped develop the Great Dust Bowl of the 1920s and 1930s.

Gardeners who practice the “no-till” method never disturb the bed once it is established. Instead, they add amendments like compost, manure, peat, lime and fertilizer to the top of the bed.  Water and the micro-organisms in the soil pull the nutrients down into the subsoil.  Instead of weeding, they use mulch to prevent weeds from germinating. The results of “no-till” gardening: good, spongy soil, rich in micro-organisms and beneficial fungi. This allows the roots of young seedlings to penetrate through the soil.

“No-Till” Gardening Benefits

Aeration and drainage

Earthworms, micorrhizal fungi and other soil organisms are keys to good soil structure. Worm tunnels provide drainage. Their excretions help fertilize the soil and bind the soil to provide for aeration. Gardeners who practice the no-till process say that their vegetable plots are freer of diseases and pests.

 

Water Savings

Good layers of mulch allow water to pass through into the soil, while shading the soil, keeping it at a more constant temperature. This is especially important in Southeast Texas, where late spring sun beats down mercilessly on garden beds. The mulch also prevents evaporation, and helps create a moist growing environment.

Less weeding

Most garden beds contain weed seeds which stay dormant until they become exposed to sunlight. Dormant weed seeds will remain dormant indefinitely in no-till gardens. Gardeners can easily remove the few weeds carried in by the wind or birds.

Saves time and energy

Some gardeners till with a shovel, turning over the soil one scoop at a

Leaving the roots of plants in the soil adds to the organic content.
Leaving the roots of plants in the soil adds to the organic content.

time. Others use gas-powered tillers. No-till gardeners save time and energy.

Keeping the carbon in the soil

Good soil has a great deal of carbon. Humus, compost and other decaying organic matter provides carbon and other carbon-dependent nutrients to plants. Tilling the soil speeds up the breakdown of organic matter. When this happens, it releases the nutrients too quickly, increasing the need for more fertilizers. Good plant growth requires a slow, steady release of nutrients. No-till gardening promotes this process.

Earthworm population

Soil without earthworms tends to be poor soil. A good earthworm population in garden soil is a good indication that the soil is healthy. Earthworms create tunnels which help water and air to filter deeply into the soil. Tilling destroys these structures. In addition, earthworm excretions (called worm castings) are extremely rich in desired micro-organisms and nutrients.

Reduces Erosion

The no-till method reduces erosion. It increases the carbon in the soil, which helps prevent fertilizers and topsoil from being washed away.

Types of mulches

Since mulch is such an important component of no-till gardening, it’s important to know what types of mulches work best. First, remember that mulch and compost are not the same thing. Mulch is organic matter that has not yet become compost.

Good sources of mulch:

  • Straw: Excellent mulching material, as opposed to hay, which may have weed seeds.
  • Pine straw: Don’t curse the pine needles in your yard. Save them for mulch. Many municipalities and homeowners are using pine straw. It degrades slowly and therefore has a longer life than many other mulches.
  • Leaves: A great source of carbon and other nutrients. After all, the largest amount of all nutrients in a plant are in its leaves. There are two easily-fixed problems with leaves. They sometimes tend to mat, and they tend to blow away. Spreading leaves in thin layers and sprinkling a little soil on each layer will help prevent both these problems.
  • Newspaper: Since paper is made of wood, these are good sources of carbon. However, newspapers tend to blow away. As with leaves, sprinkle soil between each layer.
  • Seaweed: Seaweed has a large amount of trace minerals that plants need. Slugs don’t like it, so it acts as a slug repellant as well.

Gardeners who want less strenuous work, good vegetable production, and continuous soil health might want to give no-till gardening a try.