Frequently Asked Questions

General Questions

• What is ecological restoration?
• Is there a difference between ecological restoration and naturalization?
• What are native plants?
• What are the benefits of using native plants?
• What are invasive plants?
• What is biodiversity?
• Where can I get native plant material?
• What time of year is best to plant trees and shrubs?
• How can I safely and effectively remove invasive plant species on my site?
• Do I need to prepare the soil?
• How close together can I plant?
• How much do I need to water the site?
• Is weeding necessary?
• What is the average success rate of trees and shrubs planted?
• How can we add interest to our garden during the winter?

What is ecological restoration?

Ecological restoration is the process of assisting the recovery of an ecosystem that has been degraded, damaged, or destroyed.

Is there a difference between ecological restoration and naturalization?

Naturalization and ecological restoration share the goal of restoring an area to a dynamic, self-sustaining state. While naturalization attempts to minimize long-term maintenance by planting native species, ecological restoration may require ongoing intervention to ensure the sustainability of the ecosystem. Special techniques are applied in ecological restoration beyond simply reintroducing species.

Reestablishing natural processes of succession or disturbances plays a role in ecological restoration. Burning grasslands to duplicate the benefits of natural fires is one example. Biological engineering may also be used in place of hard structures. One example of bioengineering is to use native willow cuttings as live stakes to stabilize a stream bank and prevent erosion.

What are native plants?

Native plants existed in a particular region prior to European settlement. They evolved over thousands of years to local conditions such as soil type, rainfall and temperature. Not all plants that exist in the wilderness are necessarily native. Some species have been introduced from other parts of the world. For a list of plants native to your area, visit our Native Plant Database.

What are the benefits of using native plants?

• Native species have adapted to local soil and climate conditions. This means that they will not require watering or chemical fertilizers and pesticides in order to thrive.
• Many native species thrive in poor soils.
• These species have evolved with the local bird, mammal, butterfly and insect populations and are therefore their best source of food and habitat.
• Growing these species improves biodiversity and adds to the local seed source.

What are invasive plants?

Invasive species are aggressive non-native plants introduced into environments where they did not evolve. They are also referred to as exotics, aliens, weeds, and non-indigenous species.

Invasive species spread rapidly, often displacing native species and disrupting natural ecosystems by changing the composition, structure and function of natural plant communities. Examples of invasive plants in Canada are: Purple Loosestrife, Canada Thistle, and Japanese Knotweed.

Japanese Knotweed (left), Canada Thistle (right). Left: Erich Haber, Ottawa. Right: 2004 Andy Fyon, ontariowildflower.com

What is biodiversity?

Derived from "bio" meaning "life" and diversity meaning "variety." Biodiversity is the variety of all life on earth. The variety within species and between species and ecological communities is necessary for the health and survival of certain ecosystems and organisms, including humans. It is this variety that allows living things to adapt to changing environments. Biodiversity is degraded through the destruction of natural landscapes and their invasion by exotic species. Because biodiversity has evolved over thousand of years, this loss is irreversible.

Where can I get native plant material?

There are many nurseries in Canada that provide native plant material. Visit Evergreen's online Library for a list of native plant nurseries.

Contact your local chapter of the North American Native Plant Society (www.nanps.org) and Seeds of Diversity (www.seeds.ca) for more information on native nurseries, for seed exchanges and guidelines for collecting seeds from the wild.

What time of year is best to plant trees and shrubs?

The best time to plant is in the early spring or fall when the ground is thawed and plants are dormant.

How can I safely and effectively remove invasive plant species on my site?

It is best to work with an expert to eradicate invasive plants. Different species will require different methods of removal such as pulling, mowing, or cutting. Improper removal methods can stimulate growth, so it is important to ask your local conservation authority or municipality for help. Visit the Canadian Botanical Conservation Network (www.rbg.ca) for a list of invasive species and removal methods.

Do I need to prepare the soil?

It is difficult to prepare soil over large areas. To avoid the need for soil preparation, choose native species that are well suited to the existing soil type. If a handful of soil holds together when squeezed you may have an area with a lot of clay. Choose plants that do well in clay soils. If it crumbles, you have a lot of sand. Choose species that like sandy, well-drained soils. To find species appropriate for your site visit Evergreen's online Native Plant Database.

How close together can I plant?

Evergreen advises planting a minimum of 1 metre apart for shrubs and 1.5 to 2 metres apart for trees. Young trees and shrubs have a better chance of survival when they are densely planted.

How much do I need to water the site?

Native species require less watering than non-native plants. However, all plants and seeds require more watering when they are getting started. Provide frequent and gentle watering to germinate seeds. Water more deeply and less frequently once sprouts emerge.

Trees and shrubs need to be watered immediately after planting to remove air pockets in the soil. Once the native plants are established you only need to water them after long periods of drought.

For larger restoration projects it may not be possible to water trees. Plant in the early spring or fall so the trees can be watered naturally. Choose species that are appropriate for the moisture conditions at your site and make sure they arrive wet from the nursery.

Visit Evergreen's online Native Plant Database to find species suitable for your site.

Is weeding necessary?

To grow herbaceous plants successfully, weed your garden area regularly when the plants are getting started to avoid competition. Be sure to pull out the whole weed, roots included, before it produces a seed head to prevent spreading. Trees will not require weeding if you apply mulch. Aggressive invasive species may need to be addressed.

What is the average success rate of trees and shrubs planted?

Tree guards protect newly-planted trees.

The average success rate is 80 percent. This rate ranges from 50 to 95 percent depending on varying conditions such as soil quality, wildlife populations and environmental stresses like pollution and drought. To improve the success of your trees and shrubs use tree guards, mulch and choose species that are resilient under environmental stress.

How can we add interest to our garden during the winter?

Whether you have a community garden or a naturalized school ground there are many ways to keep people interested in the site during colder months when colourful blooms are nowhere to be seen. Ask your local nursery for trees and shrubs that retain colourful bark and foliage in the winter. Attract wildlife by planting trees that yield delicious berries and by hanging bird feeders. Keep paths clear of snow as part of your ongoing maintenance plan to maintain access to the garden area and plan group activities such as observing animal tracks and tapping maple trees.

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