More on Vetiver and Carbon Sequestering

It is important to take into consideration that vetiver “plants” are in reality “clumps of plants”. When you plant 8 plants per meter to form a hedge, over the growing season in a year, those original 8 plants grow into clumps of plants that grow together to form the hedgerow. Therefore the original 8 “plants” become a far greater number depending on the fertility of the soil and rainfall. Indeed a linear km of vetiver contains 8000 clumps of plants that are bunched solidly together. It is therefore possible to imagine that 8000 clumps could indeed even sequester more than the 2.5 kg per clump estimated here.

If you look at the pictures of the root biomass of a mature “clump” – (originally an individual plant), one sees a huge mass of roots that attain a depth of 2-4 meters after two years. Root derived soil carbon accumulation is being estimated by scientific studies across the globe under both grassland and forests, either in the tropics or in temperate areas. For carbon to truly be sequestered it must be transformed to mineralized carbon aided by the microbial activity in the soil associated with the root zones. One of the reasons for high vetiver plant vigor is a result of its mychoriza (type of soil microbiological organism) association. This association is one of the reasons vetiver hedgerows produce such high amounts of biomass on the one hand and such high amounts of carbon added to the sequestered soil carbon pool.

The Vetiver Network believes that we have a means of offsetting CO2 emissions by producing an equivalent carbon dioxide savings, that is, sequestering CO2 in the soil under vetiver hedges. Vetiver hedges also have many other benefits such as soil and water conservation, pollution control, erosion control, and poverty reduction especially in the tropics. It is especially useful at the community level to provide sustainable and affordable solutions to the variety of problems facing communities who are ill equipped to deal with these problems. When you combine the CO2 offset mechanism to these other benefits and considering its ease of planting and maintenance when compared with tree planting, the argument for using vetiver becomes even stronger.

Dale Rachmeler