Industrial Hemp is bred from certified low THC varieties which have grown for thousands of years throughout Europe and Asia. Its closest botanical relative is hops.
Hemp fibre crops produce one of the most, if not the most industrially versatile and durable fibre known to humans. One hectare of Industrial Hemp grown for fibre, produces between 10 – 12 tonnes of dry fibre per ha.
Hemp fibre crops grows very rapidly ( 4+ metres in 90 – 100 days) and they are one of the most efficient CO2-to-biomass conversion tools available, 5 x more efficient than agro-forestry.
The carbon uptake of hemp can be accurately measured and monitored.
- Cellulose is 70% of stem dry weight. The carbon content accounts for 45% of its molecular mass.
- Hemicellulose is 22% of stem dry weight. The carbon content of hemicellulose is 48%
- Lignin is 6% of stem dry weight. The carbon content of lignin is 40%.
Solid state carbon is produced by the photosynthetic conversion of atmospheric carbon dioxide.
Where hemp is sustainably farmed 1.3 – 1.6 kgs of carbon dioxide are stored per 1 kg hemp fibre. The harvested and dried stem yield is what is measured when assessing a crop’s carbon sequestration.
Hemp Masonry locks up the fibre or captured carbon to form a carbon sink. The building material then continues to take carbon dioxide out of the atmosphere as it slowly cures through an ongoing carbonation process.
While Hemp needs a well prepared seed bed and adequate subsoil moisture or irrigation for the first 6 weeks (and produces optimal yields when it is irrigated), in the Northern Tablelands of NSW, high yielding hemp fibre crops have been produced with a third of the water needed for lucerne. Hemp is a hardy crop and was identified early in the establishment of the colony as a suitable crop for Australian farmers.
Industrial hemp is grown successfully using organic farming methods in a number of countries, most notably Austria and Romania. Market demand and an emerging commitment to sustainable farming is now also positively influencing production in Australia.
Hemp has a deep taproot and improves soil structure. It is an excellent crop in rotation and is known to increase yields in subsequent crops such as wheat.
When planted at appropriate densities for fibre production ( between 40 – 65 Kg seed per ha dependent on the variety), Hemp does not require the use of herbicides as the fast forming canopy excludes sunlight allowing the crop to outcompete emerging weeds. For more information on hemp farming.
A sustainable hemp building industry is dependent on regional Hemp production. Transporting a high volume, light weight material over long distances has a considerable impact on the life cycle analysis of any product.
COLLABORATIVE FARMING IN NSW
We currently source hemp from the closest possible location to our building projects and work collaboratively with farmers throughout Australia to support emerging regional Hemp farming groups.
HEMP AS A BIOREMEDIATOR
Industrial hemp has the capacity to clean up contaminated soils.
- European research (Karus and Leson, 1994) has demonstrated that hemp can be grown on soils contaminated with heavy metals, while the fiber remains virtually free of the metals.
- Kozlowski et al. (1995) found that hemp grew very well on copper-contaminated soil in Poland (although seeds absorbed high levels of copper). Baraniecki (1997) found similar results.
- The Mop Crop trial (Bolton, K., 2004) at Bangalow Sewage Treatment Works on the NSW North Coast has also proven hemp to be an excellent crop in the management of sewage effluent.