Trees Versus the Elements

Soil matters as healthy soil is vital to global food supplies.¹ An estimated 94% of our food comes from soil, but there is a problem: topsoil is being eroded away, 10–40 times faster than it is being replaced.¹

Why is this such a big problem?

Topsoil is the fertile part of soil that is eroded by the wind and the rain, and is where all the essential nutrients for growing crops are found. Without this precious resource, it will be difficult for plants, including crops, to survive. When soil degrades, it cannot hold moisture or correct environment for soil organisms.¹ 

While chemical fertilisers can increase nutrient level, this comes at a cost of inhibiting good soil organisms, such as fungi.¹ In fact, using certain chemicals can cause further problems for soil. Herbicides are often used to clear soil of weeds, removing roots that help to bind the soil.²

How can trees help?

Ploughing makes it easier for water to wash soil away. Quite often, this soil is filled with pesticides and fertilisers that, along with the soil itself, destroys the habitats of fresh-water animals.² However, the roots of many trees branch out beyond the branches. They improve drainage and hold the soil in place by preventing soil compaction and helping water to soak into the soil instead of washing over it.

Furthermore, rain gets caught in a tree’s foliage and runs down the trunk. This reduces the force on the soil and helps the rainwater to soak into the soil instead of washing over it.

Rain is not the only force acting on soil; wind also erodes soil. When they are close enough together, trees can act as windbreaks, reducing the amount of soil getting picked up and carried away by the wind.

Finally, studies indicate that crop production increases by a minimum of 200% when cultivated with trees.

Read more:

1. Griffiths A, Keightley M. ‘The secret life of healthy soil’, Your Wellbeing Garden: How to Make Your Garden Good for You (2020) London: Dorling Kindersley Limited, pp.134-7.
2. Goulson D. ‘Easter Island’, A Buzz in the Meadow (2015) London: Vintage, pp.237-52.