|Mycorrhizae form when mycorrhizal fungi infect newly forming non-woody roots as shown here.
Over millions of years, elm trees have evolved to thrive in a specific type of soil. When an elm is transplanted into a new environment, the soil is rarely ideal. The make-up of urban soil (moisture levels, mineral content and composition of organic elements) is often entirely different from the soil in which elms grow naturally. Elm trees are also susceptible to the devastating Dutch elm disease. Other things being equal, an elm tree in suitable soil is better able to cope with the disease than one in poor soil. As a homeowner, it is your job to create a more natural soil for your tree. The best way to do this is with the addition of mycorrhizal fungi.
The term 'mycorrhizae' describes a symbiotic relationship between beneficial fungi and plants. Mycorrhizal fungi live in and around the roots of most plants. In exchange for sugars and simple carbohydrates, the mycorrhizal fungi absorb and pass on minerals and moisture required for the plant's growth.
Over tens of millions of years plants have developed this symbiotic relationship with the fungus to help them survive conditions of drought, extreme temperatures and periods of low soil fertility. Mycorrhizal fungi colonize a plant's living root system, in effect extending it further into the soil - sometimes by up to 1000%! By taking in nutrients and water and passing it on the roots, these organisms are a vital link in a plant's nutrient cycle.
In nature, mycorrhizal fungi are found on about 99% of plant species, but in urban environments, the poor, compacted soils often lack this essential fungi.
Help your elm survive and thrive
Elm trees have also evolved a relationship with mycorrhizal fungi. As they are planted in urban environments, however, the relationship is often broken and elms are left to fend for themselves in hostile conditions. As a homeowner, the best contribution you can make to your elm's health is to decrease tree stress with the addition of beneficial mycorrhizal fungi to the soil.
To obtain the right kind of mycorrhizal fungi for your elm tree, click here.