Hevea Brasiliensis - Rubber: the tree behind tires
Natural rubber is inseparable from tires. To such an extent that our industry uses ¾ of the world’s production. Since rubber cultivation is therefore an extremely important concern for us, we work with producers who are mainly small-scale growers, to ensure this activity remains profitable, sustainable, and environmentally friendly.
Natural rubber, the heart of a tire
A tire is above all rubber, a large proportion of which is natural rubber. The amount used depends therefore on the size and also the type of tire.
A standard car tire contains 18% natural rubber, i.e. about 1.35kg per tire. These figures climb to 40% and 22.5kg of natural rubber in tires for heavy trucks. As for the civil engineering tire MICHELIN GC5, the biggest tire available on the market, it requires about a ton of natural rubber.
In all, the tire industry uses around 9 million tons of natural rubber every year. We are the world’s leading buyer, at nearly 1 million tons.
Rubber cultivation today
Native to the Amazon forest, the hevea brasiliensis (rubber tree) grows well in all tropical zones. Today most production takes place in South-East Asia. The principle of rubber cultivation is simple. Trees are planted, around 550 per hectare, and they are allowed to grow for 6 or 7 years. Latex can then be collected for a period of between 20 and 30 years. Collection is done by tapping. An incision is made in the tree’s bark and a cup or bowl is placed below it to collect the latex which runs out for about 8 hours. The incision then closes up again naturally. Depending on the plantations, tapping is spaced by between 1 and 5 days. A single rubber tree produces 60 to 100kg of latex over the course of its life.
The latex collected can be maintained in liquid form (by adding a little ammonia) or coagulated (by adding formic acid for instance). It is then processed in special factories where it is washed, homogenized and dried before being supplied to industry.
Small growers make big tires
Rubber cultivation is not usually done on large scale. 85% of plantations belong to small-scale owners and are less than 4 hectares in size. Around the world, the activity employs 6 million people on the plantations, to which can be added 30 million working in jobs connected to the production, trade or transformation of natural rubber.
Rubber trees offer numerous advantages to the grower. During the maturing period it is possible to grow crops between rows of trees, generating additional incomes for the growers. Harvesting, or tapping, then takes place 11 months per year. Work is therefore distributed throughout the year, and production is less subject to weather risk factors than other crops. Finally, the latex obtained is easy to preserve. Rubber cultivation enables small-scale growers to spread their activity and income. On average they receive between 70 and 95% of the final invoiced value of natural rubber.
Do tire manufacturers own plantations?
In general, the major tire companies are not directly involved in rubber cultivation. They work in partnership with producers.
Nevertheless, the Michelin group still owns a 2,000ha experimental plantation in Bahia, Brazil. We use this to undertake research with a view to improving yield and production quality
Rubber cultivation - beneficial for the environment
Rubber cultivation uses almost no fertilizer or insecticide. It does not strip the soil. On the contrary it helps to preserve it from erosion. And, above all, rubber cultivation acts as an effective carbon trap. A plantation of mature 30-year old rubber trees captures over 200 tons of carbon per year, a figure comparable to that for a natural forest.
Finally, the trees are also useful at the end of their life. Their wood can be used either to make furniture or as fuel.
Contributing to responsible, sustainable rubber cultivation
Michelin has always been a major player in the natural rubber sector
As the leading client, we are particularly keen to ensure its sustainable management, specially through the actions led by the International Rubber Study Group, an organization gathering natural rubber-producing countries and the main natural rubber consumers.
In 2016, we took a step further by publishing our sustainable policy regarding natural rubber, which formalizes our public commitments in this domain. We’re encouraging growers to use responsible practices at both the social and environmental level in order to maintain rubber cultivation within a virtuous dynamic. Michelin places its technical know-how at the disposition of the small planters.
Preserving the environment
We are doing everything in our power to control the environmental impact of rubber cultivation and to prevent deforestation. To tackle this issue, we’re working in partnership with the NGO, WWF. In parallel, we have also acquired in Indonesia 88 000 devastated hectares of land with Indonesian Barito Pacific Group. With WWF, Michelin plans to develop here an exemplary rubber plantation, from an environmental and social standpoint.
Combatting deforestation also means improving yields in order to limit the surface area concerned by rubber cultivation. We encourage all growers to use agricultural techniques that increase production whilst being yet more environmentally friendly. This means, for example, optimized management of water resources and responsible use of chemicals to treat the trees.
The best environmental practices go hand in hand with the best social practices. It is essential for the development of rubber plantations to take into account the wishes of local communities in compliance with international standards.
Together with all these good practices we maintain regular dialogue with all those involved in the natural rubber sector. We assess our suppliers on their social and environmental practices so that they comply with our standards.
Preserving the natural rubber resource
By designing more lightweight tires, that are more resistant to wear, by developing new technologies, our researchers are creating more sustainable tires, that require less raw materials and are easier to recycle.
Between now and 2050, the number of vehicles on the road worldwide is set to double. By working with everyone involved in the sector, we will be in a position to meet this demand, whilst promoting good environmental practices, enabling a sustainable management of the natural rubber sector that preserves our planet.