Everything about nuts
The Brazil nut tree (Bertholletia excelsa) is a beloved South American species prized for its namesake nuts. It’s most commonly found in Brazil, Bolivia, and Peru, and it’s one of the tallest trees in the Amazon rainforest.
This tree has been an essential source of food and income for many people in South America. Experts believe that indigenous tribes in the Amazon have been eating Brazil nuts for thousands of years.
When Was the Brazil Nut Tree Discovered?
The Brazil nut tree became known as Bertholletia excelsa in the scientific world in 1808 by the naturalists Aimé Bonpland and Alexander von Humboldt, who discovered it in one of their expeditions in the Orinoco region, in Venezuela.
The first part of the name is a tribute to the French chemist Claude Louis Berthollet. The second part, “excelsa”, means tall in Latin, and refers to the stature of the tree.
Keep in mind that this “discovery” concerns the European scientific society. The Brazil nut tree had been known to indigenous a long time before that.
How Does the Brazil Nut Tree Look Like?
The Brazil nut tree is a towering tropical evergreen that can grow up to 160 feet tall, or 49 meters. Its grayish-brown trunk has a diameter between 3.3 and 6.6 feet, or 1 to 2 meters. These trees have a life cycle of approximately 500 years.
Branches form in the upper parts of the tree. They are long and covered with oblong leaves, creating a spreading canopy. From the time they are planted, it can take up to 20 years for Brazil nut trees to produce their seeds (what we call Brazil nuts).
The tree produces fragrant yellow flowers, which will grow into fruits about the size of a coconut, around 6 inches in diameter, or 15 cm. Each one weighs around 6 pounds, or 2.3 kg. These fruits can have up to 24 seeds inside. A single tree can have up to 300 fruits.
Brazil Nut Trees Require Special Conditions to Grow
Brazil nut trees require very specific conditions to thrive. They need to be in a tropical climate with a natural and untouched environment, meaning no human interference during their reproductive cycle.
Let’s look at the most critical factors, which are so vital that they can impact the own existence of the Brazil nut tree.
These trees require a specific bee to take care of the pollination
Brazil nut trees can only be pollinated by orchid bees, the Eulaema Mocsaryi. This particular bee species is attracted to the orchids around the Brazil nut trees. Once the males land on these orchids, they collect the fragrance in order to attract females. The pollen sticks to their bodies and then falls off as they fly around, pollinating the Brazil nut flowers in the process.
The Brazil nut tree requires orchids to survive
As I just mentioned, the bees that pollinate the tree are attracted to orchids. This particular species of orchid is called Coryanthes vasquezii. Without such orchids surrounding the trees, there won’t be anything attracting the bees, and they won’t perform the pollination process.
Most of the Brazil nuts trees are planted by the agouti
The pod has such a hard shell that experts didn’t know how the seeds got out and planted on the floor. That was until they found that the responsible animal for such a task was the agouti, a rodent that feeds on Brazil nuts.
This rodent has small sharp teeth that can crack the hard shell. Once it eats some of the seeds, it carries the rest to bury and eat in the future. Naturally, some are forgotten or simply stay buried because the animal died. In such cases, the seeds can remain dormant for very long periods, until the conditions are just perfect for germination. And that’s how the life-cycle of the Brazil nut tree starts anew.
Why Is It so Challenging to Plant Brazil Nut Trees?
For most species of trees, humans can replicate their natural process. They simply take the seed, plant it in an appropriate spot, give it some water and wait for it to grow. This is not the case with the Brazil nut tree. As we just discussed, it’s tough for them to grow outside of their natural habitat. Even in a natural environment, they need a series of particular conditions that are hard to replicate.
The biggest obstacle to planting Brazil nut trees on a large scale is replicating the pollination process. More specifically, it’s tough to grow the Coryanthes vasquezii, the orchid required to attract bees, outside of the tropical rainforest. And on a large scale, it’s almost impossible. Therefore, it’s hard to find a way to get the bees to visit these trees and pollinate them in an artificial environment.
It’s safe to say that, for now, these difficulties make mass plantation of Brazil nut trees unfeasible.
Is the Brazil Nut Tree Threatened?
Another thing we can take from all the dependencies of the Brazil nut tree is that it’s very vulnerable. If any of the species it needs to survive becomes extinct, the Brazil nut tree will soon follow. If the bees die, there are no more seeds; If the orchid dies, there are no more bees around to pollinate them; if the agouti species gets threatened, planting the tree in the Amazon forest will become very difficult.
The Brazil nut tree is currently classified as vulnerable by the International Union for the Conservation of Nature.
What Are the Main Threats to Brazil nut Trees in The Amazon?
Brazil nut trees are extremely sensitive to changes in their environment. Because of this, they’re a good indicator of the health of the Amazon rainforest as a whole.
Climate change is a major threat to this species. As we know, the Amazon is a very rainy place. However, recent droughts have been affecting the Brazil nut harvests in the region, and they are expected to get worse and more frequent in the future.
Fig trees are also a danger to other trees in the Amazon forest. Small animals like birds and some mammals spread fig tree seeds. After sprouting, it steals nutrients and water from the soil, out-competing other species, such as the Brazil nut tree. After years of more fig tree roots developing, the Brazil nut tree will reach its limits and die.
Deforestation is the biggest threat to Brazil nut trees, by far. A major contributor to this problem is the plantation of soybean farms and the ranching of cattle.
The Brazil Nut Trees Can Fight Deforestation and Protect the Amazon
Soybean production may be very profitable, but it increased deforestation in South America by 10% in the past two decades. As the demand for soy grows, the deforestation increases, and the Amazon rainforest gets smaller, meaning the Brazil nut tree gets closer to extinction.
That’s why the people who depend on the Brazil nut commercialization are stepping up and fighting to protect the Amazon rainforest. They are creating cooperatives and increasing production to show their governments that this is a viable and profitable business that does not require deforestation. On the contrary, it requires the preservation of the Amazon forest.
Here is a very interesting video discussing this exact situation in Brazil. It shows the political side of this problem.
The Brazil nut tree is a fascinating species with many dependencies to germinate and grow. It’s very tough to plant them on a large scale, due to the need for an orchid and a specific species of bees to pollinate them.
Unfortunately, this tree is classified as vulnerable due to the many threats it faces, such as climate change, fig trees, and deforestation. However, the people who depend on this nut are fighting to protect it by increasing production and awareness.