1. Using Plants Sustainably

2. Sustainable Agriculture in Canada The two main agricultural practices used by Canadian farmers to increase crop yields are the use of chemical fertilizers and pesticides.

3. Sustainable Agriculture in Canada The use of chemical fertilizers releases greenhouse gases and may cause excessive growth of algae if fertilizers run off into lakes or oceans. (eutrophication) Many farmers also use manure as an inexpensive source of nutrients for crops, but they must also take care to prevent run-off into streams or standing water.

5. Pesticides The two main types of pesticides are herbicides, which control unwanted plants, and insecticides, which control unwanted insects.

6. Pesticides About 80 percent of Ontario farms use at least one pesticide annually. There are about 5700 chemical pesticides registered for use in Canada, and Canadian farmers spend over a billion dollars on them each year.

7. Pesticides The risks associated with pesticides vary with: –the amount used, –how long they last before breaking down –where they are carried by wind and water, and –whether they kill beneficial organisms, such as earthworms and insect pollinators.

8. Pesticides The more pesticides are applied, the higher the environmental risks. Insects and weeds reproduce quickly, evolving to become resistant to pesticides.

9. Affects of Tilling Tilling land is done to prepare the soil for crops and to control weeds, but it increases soil erosion and the loss of soil nutrients. Tilling disrupts wild bees. Bees are important pollinators that nest in holes in soft dirt, tangled grasses, and abandoned rodent burrows.

11. Integrated Pest Management Many Canadian farmers have adopted a variety of pest-management strategies designed to increase crop yields while reducing harmful health and environmental effects.

12. Crop rotationChanging the crop grown on a plot of land each year means that each crop is less vulnerable to specialized pests and diseases. Green manureGrowing plants and then tilling them back into the soil increases soil nutrients and improves crop health so they are more resistant to pests. Planting nitrogen-fixing crops Growing nitrogen-fixing crops, such as soybean, increases the nitrogen content in the soil, improving crop health. Biological control Natural predators, such as birds, ladybird beetles, and spiders, can control some insect pests Genetically modified crops Crops can be genetically engineered so they possess desirable traits. For example, Bt corn produces a bacterial toxin that kills the larvae of the corn borer when it feeds on corn. PheromonesPheromones are chemicals used by insects to communicate with one another. Releasing synthetic pheromones may prevent insects from mating or lure them into traps, while not affecting other species.

13. Water Management Canada has an abundance of fresh water. Canadian farmers use about 9 percent of available water for irrigating crops Irrigation reduces soil erosion because it prevents rich topsoil from drying out and blowing away.

14. Irrigating farmland carries costs. It may increase the salt content of soil, harming plants. The water may carry pesticides and fertilizers into ground water, streams, and lakes. If water for irrigation is pumped from underground sources, these sources may not refill. Water Management

15. Most Ontario farmers maintain vegetation on the edges of streams or ponds because it prevents soil erosion and reduces water run-off from the farm. Water Management

16. Maintaining vegetation on the edge of ponds and streams prevents valuable soil, polluting nutrients, and toxic pesticides from being washed into streams and ponds. Most farmers prevent livestock from grazing near water bodies to reduce damage to vegetation and keep manure out of streams and ponds. Water Management

17. Sustainable Forestry in Canada Canada has over 400 million hectares of forest, representing 10 percent of the world’s forests. Only 6 percent of Canada’s forests have been removed and the land converted to cities, farms, mines, or roads. Canadians value their forests: 13 million person-visits are recorded annually in our national parks.

18. Canada is the world’s largest exporter of timber and other forest products. Canada’s National Forest Strategy pledges a commitment to sustainable forest management. Under this policy, forest products are harvested sustainably, preserving the forest’s health and biodiversity. Sustainable Forestry in Canada

19. Preserving Genetic Variation of Canada’s Forests Canada’s National Tree Seed Centre (NTSC) in Fredericton, New Brunswick, conserves the genetic diversity of our forests. The Centre collects and stores seeds from across the natural ranges of all Canadian tree species. The goal of the Centre is to obtain a diverse collection of genetic material.

20. Preserving Genetic Variation of Canada’s Forests Seeds are collected from many individual trees in each population, not just from the “best” or tallest trees When trees are harvested, the cleared areas are planted with genetically improved seedlings grown in seed orchards. The NTSC collection is an increasingly important storehouse of genetic information.

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