For over 400 million years, trees have stood as silent witnesses to the ever-changing world. They possess the extraordinary ability to break down rocks, create soil, and harness carbon dioxide from the air, transforming it into the precious oxygen we breathe. Unfathomably resilient, trees have weathered four mass extinction events, all while rooted in place, never straying from their designated spots. Trees are enigmatic entities, vastly different from us humans. We rely on blood, lymphatic systems, and complex brains while nourishing ourselves with a diverse diet. Trees, on the other hand, flourish with sunlight and water, steadfastly growing year after year, often surviving for centuries.
When trees are in the forest, they look like single individuals fighting for sun, and water and really do not communicate with one another but this is wrong. When we look deep down into plant, we would understand that plants and trees communicate with themselves, they share resources, and share information even down to their generations. When we begin to look at plant, we begin to ask if they are competing or corporation.
Pxhere
While on the surface we see plant, there is more that keeps plant going when it comes to mutualism, and it has to do with the partnership between soil, fungi, and plants themselves and this is what we refer to as Mycorrhizal association. From tropical rain forest, to deserts, about 90% of all plant exhibit a type of mycorrhizal association. The fungus grow in association with the root of the plant forming a symbiotic relationship.
The most common type of mycorrhizal association is Arbuscular mycorrhiza, where the fungus extends its threads into the plant's root cells, creating tiny structures for resource exchange. Another class, ectomycorrhizal fungi, forms a protective sheath around the plant's roots, while its filaments penetrate plant cells, facilitating the transfer of water and essential nutrients like phosphorus and nitrogen. In return, plants provide fungi with photosynthate, the energy they derive from sunlight, ensuring mutual growth.
While fungi and trees have relationship, surprisingly, trees themselves also exhibit cooperative tendencies. Recent research challenges the notion that trees primarily compete for resources
In the early 1980s, the incline that trees work together was birthed as scientist planted pines in a box and inoculated their roots with mycorrhiza fungi to establish an underground fungi network and tagged the photosynthetic sugar by the donor pine with radioactive carbon which was sealed in the donor. With photographic film, they were able to watch how radioactive properties traveled from the donor to the recipient, as well as other materials transferred between both plants through the mycorrhiza network.
With this, researches like Suzanne Simard began to look at nutrient exchanges between trees such as the exchange between Douglas Fir Trees and Paper Birch Trees which are two different species of tree that grow together in forests. She planted Birch Fir and Cedar, with the birch being labelled with radioactive isotope Carbon 14 and labelled the fir with a stable isotope carbon 13 while leaving the cedar as control. With the label, it was easy to ell which carbon was moving from which plant and since cedar doesn't form ectomycorrhizal network, it was easy for it to be a control plant. Covering the fir from sunlight, but leaving a connection of arbuscular mycorrhiza between the two plants, the plants were able to pass nutrients to one another. Sugar from the birch was able to reach the fir even when it was covered completely without the presence of sunlight.
Trees have also shown an ability to communicate and share protective information. In a notable case study, tomato plants connected by arbuscular mycorrhiza collectively produced defense enzymes when one of them was attacked by a caterpillar. This allowed the other tomato plants to preemptively prepare for a potential invasion, thanks to the shared information.
Trees are not solitary entities, relentlessly competing for survival. Instead, they are interconnected, sharing nutrients, information, genetic material, and cooperating in ways that continue to astonish scientists. The hidden world of trees invites us to recognize their role as vital components of an intricate and cooperative ecosystem that sustains life on Earth.
Reference
https://www.mycorrhizas.info/#types
https://core.ac.uk/download/pdf/128978199.pdf
https://www.nature.com/articles/s41598-018-28920-x
https://www.jstor.org/stable/2434626?seq=1
https://www.fao.org/3/87903e/87903e08.htm
https://www.ijcmas.com/9-9-2020/Mashoq%20Ahmad,%20et%20al.pdf
https://kids.frontiersin.org/articles/10.3389/frym.2023.1194085
https://www.biohabitats.com/newsletter/fungi/expert-qa-suzanne-simard/
https://www.nature.com/articles/41557
https://journals.plos.org/plosone/article?id=10.1371%2Fjournal.pone.0013324
https://www.science.org/content/article/how-many-tree-species-are-there-more-you-can-shake-stick-new-database-reveals
https://pubmed.ncbi.nlm.nih.gov/15503185/