What Are Mycorrhizae And Why Should You Care?

Fungi are an incredibly important part of soil health. You may hear the term Mycorrhiza Fungi used referring to beneficial fungi. So, what exactly is this stuff? Basically, “myco” means fungus and “rhiza” means root. These special fungi establish a beneficial connection with plant roots and aid them with the uptake of water and nutrients. Mycorrhizae fungi have been in existence for more than 460 -million years since the first plant life appeared on dry land.

How Do Mycorrhizae Work With Roots?

After the mycorrhizae colonize and begin to multiply, they effectively increase the root area and volume by acting as extensions of the roots. The symbiotic cycle between roots and mycorrhizae results in improvements to not only the root system but also the color, foliage and overall health of the tree. Mycorrhizal fungal filaments in the soil are truly extensions of root systems and are more effective in nutrient and water absorption than the roots themselves.

More than 95 percent of terrestrial plant species form a symbiotic relationship with  mycorrhizal fungi and have evolved this symbiotic relationship over the past several hundred million years. These fungi predate the evolution of terrestrial plants, and it was the partnership with mycorrhizal fungi that allowed plants to begin to colonize dry land and create life on Earth as we know it.

Types of Mycorrhizae

There are two major groups of mycorrhizal fungi: ectomycorrhizal and endomycorrhizal fungi.

Endomycorrhizae

Endomycorrhizal fungi penetrate the plant cells where direct metabolic exchanges can occur. Endomycorrhizal fungi colonize trees as well as shrubs and most herbaceous plants and do not form visible structures.

Among the types of endomycorrhizal fungi, arbuscular mycorrhizal (AM) fungi are the most prevalent in soils. Their name is derived from arbuscule structures they form within the plant root cell.

Ectomycorrhizae

Ectomycorrhizal fungi are also found in natural environments, mainly in forests ecosystems. Ectomycorrhizal fungi develop exclusively on the outside of root cells. Ectomycorrhizae are found on trees and form visible structures.

These fungi can form visible reproductive structures (mushrooms) at the feet of trees they colonize. Ectomycorrhizal fungi grow between root cells without penetrating them. Their hyphae grow externally, forming dense growth known as a fungal mantle. These fungi form symbiotic relationships with most pins, spruces and some hardwood trees including beech, birch, oak, and willow. 

How Mycorrhizal Fungi Help Soil Health

Trees can only take in nutrients from the soil within their rhizosphere (the area surrounding their roots). This area extends only about 1/10 of an inch from the roots.

Beyond that 1/10 inch, all the fertilizer, compost, water and whatever else you add to the soil would be wasted without this web of fungi, the tree is simply not able to reach it.

That’s where mycorrhizae comes in. They spread out from the tree roots in long, root-like stringy webs call hypha and bring any needed nutrients or water back to the rhizosphere for the tree. In exchange, the tree provides carbon and sugars to feed the fungi.

In effect, the fungus provides a secondary “root system” that is considerably more efficient and extensive than the tree’s own root system, allowing it to access more nutrients. One tablespoon of healthy soil can contain several thousand of mycorrhizal filaments!

Benefits Of Mycorrhizae-Rich Soil

• Increased yield from fruit trees

• Enhanced  plant and tree growth

• Healthier root development

• Increased disease resistance

• Improved transplant success

• Increased drought tolerance

Why We Should Care

So, why do we need to know about this? Many of the regular practices we use to augment our soil actually kill the organisms in healthy soil including Mycorrhizae. This is one of the best reasons low/no-till gardening has become more prevalent over the years.  Inoculating plants with multiple varieties of Mycorrhizae and providing food that will support plant health is a necessity. Be very careful with poisons and weed killers, they can destroy healthy symbiotic relationships.

If you have questions on how to create or foster healthier soil for your trees, contact Sexy Trees today.