When you walk into the rainforests of Sumatra, one of the prominent features you notice are the buttress roots. They are distinct because of their ability to spread far and wide across the ground, their unique appearance, and their ability to absorb nutrients from the humus layer.

The roots can grow up to 30 feet above the ground and reach over 30 feet over the soil. The roots usually have an olive green/brown colour to them and sometimes they have a large growth of lichen up their sides. Recently, on our trip to Sumatra, Indonesia, we explored the rainforest and documented the wildlife that we saw there. We noticed that the roots often created a natural staircase structure. For example, when we were hiking into the rainforest to our campsite, we were going up and down the hills and we saw that the roots were really helping us walk as we were using them as staircases and railings.

Buttress roots in the Leuser Ecosystem  Photo by Jackie Pye

The Buttress roots do not go very deep into the humus or topsoil layers of the earth. On average the buttress roots only go half a metre into the ground in order to stabilize the large trees. The roots sometimes intertwine with other tree roots and create a joined mesh which can help stabilize surrounding trees. When the roots spread wider on the soil, they are able to cover a larger area for collecting nutrients. The roots stay near the humus layer because when it rains or the leaves fall from the trees, the main nutrients do not sink very low into the subsoil layer. Furthermore, the spread roots allow the trees to grow very high, giving them a strong base so they can reach high up and photosynthesize in the canopy layer.

Overall, the buttress roots are a very important element of our rainforest. They provide structure and nutrients for the trees. At the beginning of this trip we didn’t know anything about these roots, but after learning how they are all connected in some way, we managed to develop a broader understanding of the nature of this beautiful planet.

Written by Asha McDonald