Why Plants Matter: Plants in Canadian Society

Look around you

Before you read on, look around the room. The wooden table, the paper in your notebook, the cotton in your T-shirt, the toast you had for breakfast, the maple syrup on it, and the oxygen you are breathing all came from plants. Plants are so much part of everyday life that we hardly notice them.

In this unit you will study how plants are built and how they grow. We start with the big question: why do plants matter so much to Canadian society? The curriculum asks you to evaluate this, which means more than listing uses. You will weigh benefits and costs using evidence.

Seven ways plants support Canadian society

1. Food and agriculture. Wheat, canola, barley, oats, corn, soybeans, potatoes, apples, blueberries and maple syrup are all grown or harvested in Canada. Canada exports large amounts of wheat and canola, and Canada produces most of the world's maple syrup, most of it in Québec. Canola is a Canadian invention: in the 1970s, Canadian plant breeders, including Baldur Stefansson and Keith Downey, bred rapeseed into a new crop with a healthier oil.

2. Medicine. Many medicines began as plant chemicals. The cancer drug paclitaxel was first found in the bark of the Pacific yew, a tree of British Columbia's coastal forests. Willow bark contains salicin, a chemical related to the active ingredient in Aspirin.

3. Building materials and products. Canada has about 9% of the world's forests. Trees provide lumber, plywood, paper, cardboard and newer products such as tall wooden buildings made of engineered wood.

4. Erosion control. Roots bind soil, and leaves and stems break the force of rain and wind. Farmers on the Prairies plant shelterbelts (rows of trees) to slow the wind, and grasses are planted on dunes, riverbanks and road cuts to hold soil in place.

5. Recreation and ecotourism. People travel to see fall colours in Ontario's parks, hike through old-growth forests, canoe past wetlands and pick berries. These visits support jobs in many small communities.

6. Culture and knowledge. First Nations, Métis and Inuit peoples have deep, detailed knowledge of plants, built and tested over many generations and still practised today. For example, Anishinaabe communities harvest manoomin (wild rice) from lakes and rivers by canoe; many Haudenosaunee communities grow corn, beans and squash together as the Three Sisters; and for many First Nations, tobacco, sweetgrass, sage and cedar are sacred medicines used in ceremony. This knowledge belongs to the communities that hold it, and respectful research asks permission and gives credit.

7. Ecosystem services. Plants make oxygen, store carbon, filter water, cool cities with shade, reduce flooding and provide habitat for wildlife. These services are worth a great deal even though nobody sends a bill for them.

Erosion control: a closer look

When rain hits bare soil, the drops knock soil particles loose, and the water runs quickly downhill, carrying soil with it. On a slope covered in plants, leaves catch the rain, stems slow the flowing water, more water soaks into the ground, and a web of roots holds the soil together. The same idea protects farm fields from wind: a shelterbelt slows the wind so it can't lift dry soil.

What does "evaluate" mean?

To evaluate is to judge how important or how good something is, using criteria and evidence. A strong evaluation:

1. sets out clear criteria (for example: economic value, ecological value, cultural value, health value);
2. gives evidence for each criterion, from reliable sources;
3. considers costs or problems, not just benefits;
4. reaches a reasoned judgement.

Judging sources (A1.9). Ask: Who wrote it, and what are their qualifications? Is it current? Is it trying to sell something? Does it cite evidence? Government science agencies (such as Natural Resources Canada or Agriculture and Agri-Food Canada), university extension pages and peer-reviewed journals are usually reliable. A company website selling a herbal product is a weak source for health claims.

Recording sources (A1.3). Write down the author, title, date, publisher and URL as you go, so you can cite them later.

Careers with plants (A2.1)

Many Canadians work with plants every day, outdoors, in labs, in greenhouses and in offices. Here are some of the careers, with the training they usually need.

Canadian plant scientists (A2.2)

• Charles Saunders worked at the Central Experimental Farm in Ottawa and developed Marquis wheat in the early 1900s. It matured earlier, so it could be harvested before the first frost on the Prairies, which helped wheat farming spread across Western Canada.
• Baldur Stefansson and Keith Downey led the work that turned rapeseed into canola in the 1970s. The name comes from "Canada" and "oil, low acid".

These examples show a pattern: Canadian plant science often solves Canadian problems, such as short growing seasons and cold winters.