The relationship between plants, soil, and living organisms that depend on both is complex.
There is tremendous diversity at and below our feet – millions of organisms that the DIY gardener or at-home parent would know little about. There are fungi, fungus gnats, beetle grubs, invertebrates like earthworms, and an entire world of organisms we could come into contact with daily.
Many soil-dwelling organisms feed on plants, and their diet can impact their community below the surface. But before we get into that, let’s look at how plants communicate with hungry organisms in the first place.
Understanding Root Exudates
Plants release ‘exudates’ through their roots – or fluid that contains an array of molecules. Even humans do this. Think of the last time a wound or infection you had resulted in an ooze (more commonly called pus). Though our exudates may look different and secrete something different, the principle is the same.
But just because all plant roots produce these exudates does not mean the composition of the soil below them will be the same. Some exudates can be rich in carbon, and some plants can introduce chemicals into the soil community through dead cells and debris. Other factors can weigh in on this process as well, from the species of the plant to the pests or pathogens that depend on it.
Root exudates won’t remain in their natural form for long. They are absorbed and altered by soil microbes or transform into a binding agent for soil particles. And while they may take on a different form, that does not diminish their presence or impact below the surface.
More on How Plants Are Impacted
However, it’s crucial to understand that this is not a one-way street. When root exudates get produced, it also impacts the plant’s ability to pull vital nutrients out of the soil – almost like an electrical current flowing from A to B. Again, it’s a complex interaction that takes place every day that results in ongoing shifts.
On an environmental level, environmental factors can affect root exudate composition; and it could be harmful or beneficial. For example, the result could be elevated carbon dioxide levels or the deprivation of nitrogen, phosphorus, and other nutrients. You could also see a significant uptake in the same nutrients. Research suggests that neighboring plants like mycorrhizal fungi can be responsible for up to 75% of the phosphorus acquired by plants annually. Plants could see a massive decline in growth and production or, on the contrary, a productivity increase.
Last but not least, other factors (or players) could help combat a plant’s loss in growth or productivity. Beneficial soil microorganisms can out-perform harmful pests and pathogens to balance the scales. Soil bacteria and fungi, for example, can produce antibiotics that kill or inhibit the growth of bacteria. And their very existence will also stimulate a plant’s defense system.
The big takeaway is that there are delicate interactions between each plant and the soil surrounding it. We are far from understanding the full relationship between our natural systems and the direct or indirect impacts of these relationships.
Tech Terra Environmental offers ecological solutions for tree and turf care professionals. We specialize in environmentally conscious application products to improve plant and soil health for lawn care providers, landscape contractors and municipalities & schools in the tree and turf care industry. Please call to speak to a specialist at 609.468.1905 or email info@techterraenvironmental.com