Biochar for Ecological Restoration
Biochar for land and forest restoration (credit: Thomas Howe/Haleakala Biochar)
Mark Twain visited the Hawaiian islands in 1866 and considered them to be one of the most beautiful places on Earth saying they were the:
"loveliest fleet of islands that lies anchored in any ocean. I feel the spirit of its wild lands, I hear the splash of its brooks; and in my nostrils still lives the breath of its flowers"
Little could Twain have expected that large parts of those once verdant islands he visited in the mid-19th Century would become 'weed patches' in the 20th. However, by applying principals of ecology, new technology, and managing the results, projects are underway to reverse some of the damage and revitalize landscapes now covered in weeds.
Biochar is a manufactured product being used to restore degraded lands on Maui. An excellent example is being demonstrated on the island where an invasive tree is being removed and native species replanted. The US Forest Service advises using biochar if large volumes of wood waste is available when dead or decadent vegetation is removed to reduce the chance of wildfires. Previously, the material was piled-up and burned or left to decompose on site. When converted to biochar, the product offers opportunities to economically restore degraded landscapes, large and small.
Biochar is produced by pyrolysis, the heat-driven conversion of organic matter under conditions of low oxygen and high temperature. The process is similar to making charcoal but at lower temps. The debris is shredded into a uniform size, loaded into a sealed reactor, and 'cooked'. The resulting black material has unique chemical and physical properties including high structural porosity allowing excellent absorption of water and nutrients. Biochar maintains these constituents in soils where it is added, like a compost, to become a stable, slow-release source of carbon, nitrogen, and other minerals necessary for plants roots as they become established. It has wide utility in soil regeneration, plant growth, and sustainable agricultural practices.
On Maui a local company, Haleakala Biochar, produces this natural product from waste generated by removing non-native Eucalyptus trees introduced to Hawai'i from Australia in the 19th Century. The trees became a weed by producing copious volumes of seeds dispersed on the winds and affecting its local environment by leaching toxic chemicals produced in its leaves. Those compounds inhibited the germination of any non-Eucalytpus species allowing them to dominate once-diverse, native Hawaiian forests. The Australian tree, along with several invasive fodder grasses, contributed to the massive fires that consumed parts of Maui recently. Nature Magazine presented how availability of such flammable species fueled deadly blazes elsewhere they have been widely planted.
Biochar reactor and landscape restoration project on Maui (credit: Thomas Howe/Haleakala Biochar)
The Maui-based company is located on the slopes of Haleakala, the massive volcanic crater set aside 1916 as a national monument under the Antiquities Act. Their biochar is used in agricultural, home garden, land restoration, and storm water filtration projects to help regenerate soil fertility. Removing the Eucalyptus trees and converting the chipped residues to biochar has allowed for restoration of native forests where they once grew. The revitalized landscapes have become new habitat for endangered wildlife including the endemic Hawaiian honeycreepers. Streams once dry, having being desiccated by the Eucalyptus, have begun to flow again.
Restoring balance to any damaged landscape, river, or marine environment requires the application of ecological principals; developing 'buy-in' from affected individuals or communities; and managing the process to realize the best chance of long-term success. When this approach is followed, the results can be remarkable and offer hope for even further recovery. The Company's founders follow a mindful motto coined by the environmental writer Wendell Berry:
Care of the Earth is our most ancient, most worthy, and most pleasing responsibility. To cherish what remains of it, and to foster its renewal, offers legitimate hope.
With wide applications of projects in landscape and forest renewal in Hawai'i, visitors may again see beautiful and verdant views someday like those Twain so relished. WHB