Plants and Their Roles in Nature and Society
Canola: A Canadian Success Story
Canola, originating from "Canada" and "oil," is a plant improved via traditional breeding and genetic modification; its oil is low in saturated fats and used for biodiesel. The leftover meal serves as animal feed.
Food Crops
Most human food comes from 14 agricultural crops. Canada’s main crops are wheat, canola, barley, corn, soybeans, potatoes, flax, and oats.
Angiosperms
Almost all crops are angiosperms. Cereal grains and legumes are the most important crops. Half of the world’s protein comes from cereal crops, and 15% from dried legumes.
Plant Parts as Food
We eat all parts of plants: leaves, stems, roots, seeds, edible fruits, spices, and herbs. “Hidden” plant products include sugars, oils, thickeners, and soy protein.
Plants as Pharmaceuticals
Plants have been used as medicine (e.g., willow bark for pain). 25% of modern drug prescriptions contain plant products.
Medicinal Plants
Over 500 plant species were used by Canada’s Aboriginal peoples for medicine. Taxol, from the Pacific yew, treats cancer (synthetic methods developed to prevent extinction). Only a small fraction of plants have been investigated for medicinal properties.
Plants: A Source of Fuel
Plants have been a primary fuel source for over 50,000 years. Biofuels like ethanol and biodiesel are derived from renewable organic materials, but have drawbacks including energy requirements and land use.
Plants: Industrial & Building Materials
Plants are used in construction and industry. Hardwoods and softwoods are used for furniture and building. Canada’s softwood lumber industry is worth billion per year. Other uses include linseed oil and castor oil. Original plastics were made from corn.
Other Uses of Plants
Plants are used for pencils, ink, paper, and clothing (cotton, linen, etc.). They provide ecosystem services like nutrient cycling, detoxification, erosion reduction, and habitat.
Using Plants Sustainably
Sustainable use means using only what can be replaced, protecting biodiversity. The UN defines sustainable development as meeting present needs without compromising future generations.
Sustainable Farming
Sustainable agriculture projects have increased yields. Practices include raising fish with rice, changing transplanting methods, ending tilling, and planting trees among crops.
Agriculture in Canada
Canadian farmers use chemical fertilizers and pesticides, which pose risks like greenhouse gas emissions and resistance. Tilling increases soil erosion.
Pest Management
Integrated pest management reduces chemical pesticide use.
Water Usage
Canada has abundant fresh water. Irrigation reduces topsoil erosion but can increase soil salinity and cause runoff, water management is vital.
Forests in Canada
Canada has million hectares of forest. million hectares are sustainably managed. The National Tree Centre preserves genetic variation.