Reference Material for Biodiversity Activity Sheets

Hi, teachers and keen parents!

Here is some curriculum information and some reference material that you may be interested in.    We are going to be updating this page soon, so visit again - lots to do with this very fast turn around with this biodiversity project!

First up: Grade 6 Ontario curriculum 

Understanding Life Systems: Biodiversity

Big Ideas

  1. Biodiversity includes diversity of individuals, species, and ecosystems.

  2. Classification of the components within a diverse system is a beginning point for understanding the interrelationships among the components.

  3. Because all living things are connected, maintaining diversity is critical to the health of the planet.

  4. Humans make choices that can have an impact on biodiversity.

Overall Expectations

  1. Assess human impacts on biodiversity, and identify ways of preserving biodiversity.

  2. Investigate the characteristics of living things, and classify diverse organisms according to specific characteristics.

  3. Demonstrate an understanding of biodiversity, its contribution to the stability of natural systems, and its benefits to humans.

OUR TREE PAGE

This page has detailed info on each tree species native to Ontario.  It includes a map from our Ontario Tree Atlas Project, a volunteer citizen science project that collected data on our tree species ranges.  Click here to go to the page.

NATIVE VS NON-NATIVE

Terminology

In the botanical world, the term native species is up for debate and different sources will have different definitions. That being said, most definitions address 2 common themes. The first common theme is geological specificity. Native plants can be described as naturally occupying a specific region or habitat and plants from outside that region or habitat are not native to it. As such, a native species is usually given a geographic qualifier to describe where it is native to (i.e.all plants native to Ontario is native to Canada as well, but not all plants native to Canada are native to Ontario). The second common theme  is a lack of human intervention. Plants that have been artificially selected for and did not evolve naturally in an ecosystem cannot be considered native. Plants that are introduced by humans to an area or habitat that they do not naturally occur in are also not considered native. In all, a native species can be described as a species that exists in a specific area without direct or indirect human intervention. 

Definition of a native species

Non-native species are species in an area that falls outside of this definition. They may be non-native because they are exotic and do not belong to the specific region, or they may be non-native because they are a cultivar and bred by horticulturalists (through cloning or hybridization) for specific traits. 

Nativars are cultivars of native species selected for specific traits (i.e. colour, growth performance, etc.) that differ from the wild-type of the species. They are bred clonally (of a desired individual) or by hybridization. Cultivars are indicated in their scientific name after the genus and species name (the first letter is capitalized and the word is often set off by single quotation marks)

Why people use non-natives

From a conservation standpoint, it makes sense to plant native plants as they are the species that the other parts of the ecosystem has evolved with but there are also motivations for using non-native species.

Some scenarios in which a non-native species may be planted include:

  • Some non-native species are planted for economical reasons to improve an industry. A lot of crop species that are grown may not necessarily be native but they may be grown for food or medicinal purposes. A lot of forestry plantations can also include exotic species. 
  • Non-natives may also be grown for human enjoyment. Ornamental plants are plants that are grown for decorative purposes in gardens and landscapes. The plants that are chosen may be picked based on aesthetic reasons and therefore may not necessarily only include native species.
  • Non-natives species may also be intentionally introduced to an area with the aim of addressing environmental issues. An example would Scots Pine, which in the past had been introduced to areas to reduce erosion. 

Some benefits of using a non-native species include:

  • A non-native species may be less susceptible to an invasive pest. Disease and insect pests co-evolve with their plant hosts in an arms race for the upperhand. This means that these plant hosts may be better equipped with defenses to resist or survive these pests than plants that have not encountered the pests before. The problem is, Ontario is a host to several different invasive pests that our native plants have not evolved with and are therefore susceptible to. Certain non-native species (that are also resistant to native pests: Japanese Maple (Acer palmatum), Katsura tree (Cercidiphyllum japonicum),Turkish Filbert (Corylus colurna), European Hornbeam (Carpinus betulus)) may have a better chance of surviving in areas where these pests are a problem.
  • Some non-native trees are very genetically isolated, making them more pest resistant. Some non-native plants are not closely related to any other species (ex. Ginkgo biloba is the only species in its genus). This means that there is less of a chance that few pests have co-evolved with similar plants and therefore be well equipped to attack it. 
  • Non-native plants may be better adapted to extreme planting conditions and environments. Not all planting environments will be very hospitable to plants- some garden locations may have a thin soil layer, or be exposed to high sun or wind. While there are native plant species that can handle this, it is a limited selection. Non-native species that are from an environment that is similar to the growing conditions may survive better than many native species and offer more variety.
  • Non-native species can flower at different times of the year. In an ornamental garden, choosing non-native species and cultivars may mean you can have more options for plants that flower at different times. By planting a variety of species, you can stagger the flower season of each and have blooms for a longer time. 
  • Different cultivars are bred for beneficial qualities. Cultivars may be bred for increased yield and growth, which is beneficial for agriculture. Ornamental cultivars also provide display options that the wild-type may not.

Problems with non-natives

There are a few issues that come up with planting non-native species.

  • They do not promote the same biodiversity in the ecosystem. Native plants do a better job of hosting and supporting local insect and herbivore communities. Ontario wildlife has co-evolved with native plant species and may not be as adapted to use non-native species. Research also shows that native pollinators and herbivores do not find non-native plants as attractive as a food source as they do native plants. Nativars that have different colours and patterns are also shown to be less attractive to insects as their wild-type native counterpart. 
  • Non-native species may become invasive. Some non-native plants can escape the confines of a garden where it is planted and become an invasive species. This happens when the non-native species have seeds that are easily dispersed and grow aggressively (more so than native species). This leads to the non-native plant out-competing native plants for sun, nutrients, water, etc. The ecosystem biodiversity then suffers as all the plants and animals that depended on those native plants are affected. 
  • Nativars have poor genetic diversity. To maintain the desirable traits of many nativars, they are grown asexually from tissue culture and are therefore clones of each other. Since genetic diversity is the key to a healthy population and ecosystem, this is a problem. Poor genetic diversity means poor adaptability to changing environments. In the event of a disease, a genetically diverse population will have individuals with a genetic makeup that allows for resistance. These individuals can therefore survive and maintain the population. In a population where all the individuals are genetically the same, this doesn’t happen and the whole population might get wiped out.

INVASIVE SPECIES

An invasive species is any kind of living organism that is not native to an ecosystem and causes harm either economically, environmentally, or ecologically. This is similar to an introduced species (in this case, often an ornamental tree), which is any kind of living organism that is living outside of its native range and has arrived there by human activity, either deliberately or accidentally. 

An introduced species might establish invasiveness in a new ecosystem due to a number of different factors. Invasive species often lack predators or another source of population control in their new habitat, are able to adapt easily to a range of environmental conditions, and reproduce at a rapid rate. Some traits of non-native plants increase their likelihood of becoming an invasive species, and these traits are often very similar to the desired characteristics of ornamental plants. The EDDMapS: Identifying and Mapping Invasives handbook (2008) compares the characteristics of invasive and ornamental plants in the two lists below: 

Characteristics of invasive plants:

  • Habitat generalist

  • Outcompetes other plants

  • Reproduces easily

  • Produces many seeds

  • Seeds are easily dispersed

  • Not affected by native pests/diseases

Characteristics of ornamental plants:

  • Hardy 

  • Easy to grow and propagate

  • Produces many flowers

  • Fruits to attract birds

  • Disease and pest resistant

While the native range of a species can spread naturally, invasive species tend to be spread via human activity because it has the potential to travel farther distances. Due to global trade and transport, species may unintentionally be moved to new locations through contaminated packing materials, in cargo holds of ships, in contaminated produce, and more, where they have the potential to become invasive. Pets and ornamental plants may also escape into the wild and become invasive. They can then be hugely detrimental to local habitats by outcompeting native species, reducing biodiversity, and changing the conditions of the ecosystem.

Examples of Invasive Species

Common Buckthorn, also known as European Buckthorn, is native to Europe and is an invasive species in Canada. This shrub spreads rapidly in a wide range of habitats and is harmful to the environment by outcompeting native plants, reducing biodiversity, degrading the quality of wildlife habitat, and impacting many different industries. 

Norway Maple is native to Europe and was originally brought to North America to be planted for shade. This species may shade out native understory plants such as spring wildflowers and may outcompete native tree species in the forest. This may reduce biodiversity in the forest and change the structure of the forest habitat. 

Amur, Morrow, and Tatarian Honeysuckles are species native to Asia and are also called “ecotic bush honeysuckles”. These shrubs can quickly overtake an area and change the habitat by shading out native plants, depleting moisture and nutrients from the soil, and possibly releasing toxins to prevent other plants from growing nearby. 

Oriental Bittersweet is a woody vine native to Asia and originally introduced to North America as an ornamental plant. This plant can cover, shade, and outcompete native plants. It can also hybridize with the native American Bittersweet, which reduces the population of this native species as it loses its genetic identity. 

Giant Hogweed (not a tree) is native to southwestern China but came to North America originally as a garden ornamental. It looks similar to the native Cow Parsnip and Angelica but is much larger. Following contact with the skin, the clear sap from this plant can cause skin sensitivity to sunlight resulting in blisters. Contact of the sap with the eye can cause temporary or permanent blindness. 

Emerald Ash Borer (insect) is native to China and eastern Asia, and it is an invasive forest pest in Canada. It was likely introduced to North America through imported wood packaging and spread through the movement of infested ash materials such as firewood. This beetle attacks both healthy and stressed ash trees as the larvae tunnel through the tree’s vascular system, eventually killing the tree.

Negative Effects of Invasive Species

Invasive species can have a number of detrimental effects on the environment. Due to their ability to spread quickly, invasive species may:

  • Outcompete native species for space and resources

  • Displace native species

  • Decrease habitat and resources for wildlife that rely on native plants

  • Degrade soil quality

  • Affect nutrient cycling

  • Reduce the biodiversity in an ecosystem

  • Cause or carry disease that negatively impacts native species. 

In addition to direct impacts to the environment, invasive species may also have large indirect impacts that affect the entire ecosystem by altering the food web and influencing all of the interconnected relationships between different organisms in the ecosystem. Native wildlife tend to rely on native plants for food, with usually little interest in non-native species. Should an invasive species displace a native plant species, it will impact all of the animals that rely on the plant for food and resources. As well, increased grazing and use of remaining individuals of the native plant species may occur due to diminishing availability, putting even more pressure on the remaining population. All of this may contribute to loss of biodiversity within the ecosystem. 

As well as the ecological damage, invasive species can also be harmful economically through its ability to:

  • Reduce crop yield and production

  • Be very expensive to control and remove in an infested area

  • Affect the jobs of people working in industries that rely on the affected resources 

  • Decrease the value of ecotourism in the affected areas

  • Threaten the integrity of national and provincial parks, nature reserves, local parks and trails, urban canopy, private gardens, and all related products or programs.

Therefore, it is important that invasive species are identified as early as possible so that measures can be put into place to control or prevent the infestation.