Cannabis

Cannabis is a remarkable plant that has been used throughout history for a wide variety of different purposes. It is believed to have first been cultivated in Eurasia and then spread by humans throughout the rest of the globe. The plant can provide food, fiber, shelter, clothing, medicine, nutritional fats and amino acids, spiritual aid, fuel, and even has beneficial essential oils! There are many unique variations of the cannabis plant throughout the world, the distinct cultivars specific to certain locations are known as landraces. These unique expressions of the same place arose and diversified as cultures throughout the world selectively bred the plant for their desired purpose. It was discovered in a bridge abutment built in the 6th century in France, that’s a long lifetime! Cannabis has been a very beneficial plant throughout history and it was only in the last century did its use drop. A decline in demand for fiber along with a rise in competition from other natural plant fiber sources reduced interest in hemp. This, coupled with the propaganda campaign against the cannabis plant, led to the crop being prohibited in most of the world during the late 20th century. The distinction between cannabis plants that can be used as a psychoactive drug (marijuana) and plants that can be used as a building material (hemp) generally lies in the amount of THC (tetrahydrocannabinol) present on the plant. THC is the main chemical compound that produces a high from cannabis and it is present in only tiny amounts in industrial hemp. Industrial hemp is generally very tall whereas marijuana plants are bushy and heavily laden with dense flower buds.

Industrial Hemp

 

Renewed interest in the cannabis plant has sent people searching the world to find undiscovered landrace cultivars that could provide a key sustainable source for many of humanity’s needs and desires. Hemp may help the construction industry to transition away from highly polluting, carbon intensives solutions, to more sustainable ones.

One of the most common ways that hemp is used in construction is as hempcrete bricks that infill between a load bearing frame. The inner, woody core of the hemp plant is combined with a lime-based binder to form an insulating block that weighs only 1/7th the amount of concrete. Fully cured bricks even float in water. Hempcrete has good thermal and acoustic insulating properties, and it can passively regulate humidity in a built environment, this helps to decrease the risk of vapor condensation and increase thermal comfort. The interaction between the silica in hemp and lime causes hempcrete to mineralize over time which makes it rot, mold and fire resistant.  Different formations, in terms of density and composition, of hemp mixtures can be used for different purposes, from block walls to filling materials, to roof and floor materials, to indoor and outdoor plasters. Hemp captures CO2 as it grows and the carbonation process, where the silica in hemp bind with lime and cement, also absorbs more CO2 and stores it for the lifetime of the building. This means that hempcrete blocks have a negative carbon footprint and if they were used widely, they could help reduce the massive environmental impact of the construction industry. Exact estimates of hemp’s carbon storage ability and environmental sustainability very depending on site climate and soil conditions.

 

References

Arrigoni, A., Pelosato, R., Melia, P., Ruggieri, G., Sabbadini, S., & Dotelli, G. (2017). Life cycle assessment of natural building materials: the role of carbonation, mixture components and transport in the environmental impacts of hempcrete blocks. Journal of Cleaner Production, 1051-1061.

Clarke, R. C., & Merlin, M. D. (2016). Cannabis Domestication, Breeding History, Present-day Genetic Diversity. Critical Reviews in Plant Sciences, 5-6.

LimeTechnology, A. (2017, 06 07). What is Hempcrete? Retrieved from american limetechnology: http://www.americanlimetechnology.com/what-is-hempcrete/

Zampori, L., Dotelli, G., & Vernelli, V. (2013). Life Cycle Assessment of Hemp Cultivation and Use of Hemp-Based Thermal Insulator Materials in Buildings. Environmental Science & Technology.

 

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More Food, Less Work

Iain Richardson

Brent was such a wonderful and hilarious character. His laid-back approach to gardening was practical,  refreshing, and surprisingly effective. Why cut down an apple tree if it has tipped over and looks funny but still produces apples? In his old age, Brent loves being able to pick them by himself, without needing a ladder or a long grabbing stick. This image of a bent over apple tree reminds me of Brent’s style of gardening.

He seemed content just letting the trees run wild and then adapting to them as need be by taking the path of least resistance and by working hard when necessary. Another aspect of Brent’s life that I admired was his connection to the land. He has been on Linnaea Farm for more than thirty years and has watched trees grow from tiny seedlings to giants. Having a long-term connection to one home and the desire to stay there for the rest of my life is not something I have experienced much of in life. Housing, no matter how lovely the place, always feel temporary because life have so much to offer and so many places to explore that I cannot imagine settling down anytime soon. However, Cortez Island does feel like a place I could call home one day, a place I could plant trees and watch them grow, mature, and continue on after I die. Something else I admired about Brent was his ability to be content with life and to forgive himself for not always doing the things he thought he could or”should” do. I have noticed an ingrained pressure from society to always be busy, accomplish things, and make a mark in life. Brent reminded me that there is beauty in just being alive, doing what you can, and letting go. Living connected with the cycles of nature, rather than a life dictated by alarms and digital clocks, is still a viable way to live life. It just might take some radical life changes.

Radical life changes are what I have in mind after I got back to this strange place we call a city. I am probably going to move to Saltspring Island shortly and join a permaculture farm, or live in the mountains with a pack of wolf-dogs, a herd of goats, and a flock of geese.

Another aspect of Brent’s life that I admired was his connection to the land. He has been on Linnaea Farm for more than thirty years and has watched trees grow from tiny seedlings to giants. Having a long-term connection to one home and the desire to stay there for the rest of my life is not something I have experienced often. Housing, no matter how lovely the place, always feel temporary because life have so much to offer and so many places to explore that I cannot imagine settling down anytime soon. However, Cortez Island does feel like a place I could call home one day, I place I could plant trees and watch them grow, mature, and continue on after I die.

Radical Earth Muffin PermaCult Leader

Iain Richardson

Oliver was inspiring, radical, and extremely knowledgeable.  He challenged conventional social norms and the legitimacy of consumer culture  \in order to restore the environment, and provide food for people. His perspectives regarding the globalization of species and the futility fighting “weeds” in order to conserve a historically accurate ecosystem opened my mind to a new paradigm for restoration ecology. In order to avoid societal collapse caused by catastrophic climate change, society must prioritize regeneration of earth’s vital life support systems (ie. climate regulation, water purification, pollution remediation, biodiversity/food production, etc.) over the classical restoration philosophy where historical fidelity is key. To give a simple example, I would prefer to spend my life planting fig trees along the west coast and creating delicious new ecosystems, rather than pulling out scotch broom.  Figs are a highly productive tree that grows well on cliff slopes, stabilizing the soil and providing food and habitat for a variety of species. They may be key to limiting scotch broom’s ability to dominate coastal bluff ecosystems because figs can survive the harsh, exposed conditions and create a great deal of shade, which scotch broom cannot tolerate. They are also easy to propagate from cuttings, they can tolerate living in pots for long periods of time, and they are commercially valuable! Rather than looking to governments and big business to change how society produces and acquires goods, people can take matters into their own hands and grow plants that satisfy human needs and give back to the planet. The renegade gardens that Oliver created revitalised common spaces that inhabitants to use to play, explore, and experiment in nature. The high price of real estate has left many people cut off from their innate need to connect with the land that sustains them. Oliver has helped to facilitate a revitalization of the commons and spark connections between like-minded community members. The gardens provided hope, education, and sustenance for the surrounding neighborhood, which were often lower income with immigrant and at-risk populations. Wisdom gained from generations of living sustainably on the land can be preserved and passed on from the elders to their new community.  Oliver learned many of his early permaculture lessons from his elderly, Asian neighbors who pointed out the many things he was doing ineffectively in the garden. These projects seem like a great way get our elders back to the earth and into the community rather than them being stuck inside a building watching T.V alone.

This picture, from a Vice documentary about Oliver’s climate change adaptive tree project, really reminds me of our time on Cortez learning from Oliver and his quirky, awesome personality.