That the word 'root' has been given the dual purpose of both honouring our human origins and describing an essential part of a plant emphasizes how humans see ‘roots’ as being essential to the success of life in this world. We both originate from our roots—it is the health of those roots that enables humans and plants to thrive.
When roots emerge rapidly into favourable conditions, they will explore and find other organisms to share and prosper with, leading to long and productive lives. Nurturing these roots is a skill above all others because it is fundamental and essential.
Just like humans, the roots of a plant needs air, nutrients, and water. Trees live hundreds, even thousands of years, and so their root system needs to continually adapt to and explore the site they seeded into. This is only possible because water and air exchange continually occurs throughout the soil mass.
When we speak of human roots, we are also talking about hundreds and thousands of years, except humans have the ability to move from where they first put their roots down—as humans we have moved around the planet using water and air, without regard for the ecological consequences.
Humans are not dependent on one site for their air, nutrients and water but instead import these components—especially into cities that we have created and populated. We have devised ‘roots’ outside of the soil. Trees do not have this luxury, yet they do have the ability to live many human lifetimes.
Photo by Jeremy Bishop on Unsplash
A tree that is planted in the city remains in one place throughout its life and yet we expect its roots to adapt to its circumstances and thrive. The hard surfaces which cover most of a city’s surface area divert water away and seal air from circulating in and out of the soil. Yes, compaction enables the hard surfaces and buildings to remain stable but physically stops root exploration.
Even if the soil mass provided for a tree has nutrients, the plant cannot access them if it is unable to breathe and absorb water. And so the tree may live for a while but dies after a short life because its roots have been denied the ability to thrive or even survive.
We’ve known for some time that half of the trees we plant in cities die by the twentieth year after planting, and most of the surviving trees live just one quarter of their normal life span. These tree losses are almost solely due to not recognizing the fact that roots need regular air exchange and readily available water to live—just as humans do. We know the problems and have the solutions. If we think of a tree’s roots as needing what human roots need—clean air, water, and food—then we will be creative in giving city trees what they need to thrive.
Photo by Felix Mittermeier on Unsplash