When the roots of one tree have direct contact with the roots of another, their vascular systems can actually merge. These trees then share water, carbon, nutrients and chemical messages through these root grafts. Recent research suggests that trees are communicating through these grafts and through their mycorrhizal fungi connections, which has been christened the wood-wide-web. Trees also communicate through airborne chemicals through the use of pheromones and other scents. If an insect attacks one tree, that tree sends chemical signals to the trees in a circle around it and all those trees change the chemistry of their leaves to make the leaves less palatable for that insect.

Additionally, "Studies have shown that trees can recognize if their neighbors are family." They even nurture their own seedlings and often form alliances with trees from different species.

Forests capture and store the largest amount of carbon on the planet, second only to oceans. They provide habitat for over half the species on the planet, they help regulate the rain, clean the air and bring us a sense of peace and majesty in their presence.

In Amma’s booklet, Man and Nature, published by the Amritapuri ashram decades before the current research on the benefit of trees, Amma said,

"Science has yet to understand the various benefits that forests bestow on nature. They are indispensable. They purify and prevent the overheating of the atmosphere, they keep the soil moist, they protect and preserve wildlife. You may feel that destroying a tree or a plant is less wrong than killing a human being. This concept is wrong. In order to meet the necessities of life, it is not wrong to cut down trees and collect medicinal plants from the forests. But we must not exploit and destroy the forests. When the ancient sages encouraged us to worship trees, they were teaching the world the importance of preserving and protecting nature. Trees purify the atmosphere absorbing the carbon we exhale. They greatly assist the harmony of nature. Even mentally worshiping and protecting the trees, that bring us so much good, is beneficial."

Urban forests, too, are now being acknowledged as vital planetary ecosystems that have been overlooked for the benefits they have selflessly given us for thousands of years. Towns and cities, at this moment in history, house more than half the worlds’ population. And the importance of urban forests for the health of the people in these cities, and for planetary health, is beginning to be recognized.

Replenishing trees in both the worldwide traditional forests as well as in all urban forest environments, plays a vital role in healing the planet and reducing the effects of climate change. Amma has been encouraging us for many years to grow and plant trees.

"Everyone should grow trees and plants in their yard. Planting a tree is a selfless service to society. Plant trees. It is a blessing to do so. Trees outlive us and provide fruit and shade to coming 1 generations. Just as we enjoy the presence of trees planted by people in the past, we too should plant for future generations. If we haven’t done any selfless acts, we should plant a tree or sapling, that would be a truly selfless deed, benefiting others and ourselves."

Trees cool and reduce the 'heat island effect' in cities, reducing the temperature produced by so much hardscape (such as cement and asphalt) by up to as much as 20 degrees Fahrenheit (11 degrees Celsius). Trees provide habitat for numerous birds, animals and insects, absorb CO², reduce carbon emissions, improve air quality and have even been shown to improve physical and mental health for residents by reducing blood pressure and stress.

Urban nut and fruit trees have also helped reduce city food insecurity. In the city where I live, for example, Food is Free Albuquerque (a nonprofit group) collects ripe fruit and/or nuts, if residents don’t want the harvest, or have too much of a harvest, and they give the surplus to families in need, food banks and shelters. Approximately 25,000 pounds of food was harvested in 2022 alone.