Native Trees

Objective

To produce a list of native trees and shrubs of the Ottawa area. We hope that homeowners, communities, and developers will consider planting some of these species, which are adapted to our climate and are part of the local ecology, instead of opting for exotic and horticultural varieties. We believe that planting trees and shrubs that are native to our landscape and that attract wildlife will go a long way toward restoring a natural, balanced environment and make Ottawa a green capital.

Criteria

We searched Farrar (1995) for trees and large shrubs and Soper and Heimburger (1982) for shrubs that are common in the Ottawa area. We excluded species like American Elm and Butternut that are prone to disease. We then cross-referenced the list against Gillett and White’s Checklist of vascular plants of the Ottawa-Hull Region, Canada to rate each species as common, sparse, rare, etc. in our area. The list currently consists of 22 large trees, 21 small trees, and 32 shrubs.

These 3 sources provided names (common names in English and French and species names), natural habitat, size at maturity, general form, prevalence, and some light and soil requirements. We searched the Internet for information about landscaping with native trees and were able to add soil, light, and moisture requirements for each species as well as information about how they behave in an urban situation (for example, species that are not good near cars because they drip sucrose). We referred to a City of Ottawa compiled list showing salt tolerance (although this should be used only to determine which trees can be safely planted near roads and sidewalks and should not influence choices for backyards, parks, etc.). We referred to Hanrahan (2002) for wildlife uses and The butterflies of Canada (1998) to determine which are larval food sources.

Next steps

We would like to add availability to our database (can you buy this species in the Ottawa area). And replace form, which tends to be rather technical, with at least one photo for each species. Several photos would be best, showing both young and mature trees (as people buy these trees when they are no more than 5 years old), and interesting features, if any, like flowers.

Uses for the database

On our web site, we are starting to feature a "native tree/shrub of the month." A photo is accompanied by information from the database and links to articles or other information on our web site.

The database can reside on our web site with an interface that will allow the user to choose from a number of characteristics, e.g., flowering shrub, easy to grow, drought tolerant, etc.

We would like to produce a brochure, explaining why it’s a good idea to plant a native tree/shrub rather than non-native. We would include lists of some species from our database as alternatives to those promoted by nurseries, e.g., plant a Sugar Maple or Mountain Maple instead of Norway Maple; plant a serviceberry or elder instead of Japanese Lilac. It would be great if we could get this brochure into the "kits" that are given to new homeowners in development. We could also distribute it through City information centres and possibly at nurseries.

We would also like to produce "fact sheets," photocopied onto an attractive template, along themes, such as,

Easy-to-grow native trees and shrubs

Native trees and shrubs for birds

Native trees and shrubs for butterflies

Native trees and shrubs for dry areas

Native trees and shrubs for damp areas

Native trees and shrubs for sunny yards

Native trees and shrubs for shady yards

Data sources

Farrar JL. 1995. Trees in Canada. Markham, Ont.: Fitzhenry & Whiteside, and Ottawa, Ont.: Canadian Forest Service, Natural Resources Canada; 1995. (F, natural habitat for trees)

Gillett JM, White DJ. Checklist of vascular plants of the Ottawa-Hull Region, Canada. Ottawa, Ont.: Canadian Museum of Nature; 1978. (G&W, prevalence in our area)

Soper JH, Heimburger ML. Shrubs of Ontario. Toronto, Ont.: Royal Ontario Museum; 1982. (S, natural habitat)

Brand MH. UConn database of trees, shrubs and vines. Storrs, Conn.: University of Connecticut; 2003. Available at www.hort.uconn.edu/plants/index.html (viewed 9 August 2003) (UConn, growing conditions; [also has "landscape use" and "liabilites," which I did not use])

Suffling R, Eagles P, Lamb L. , July 1997. Recommended list of trees and shrubs for University of Waterloo plantings. Waterloo, Ont.: University of Waterloo; 1997. Available www.adm.uwaterloo.ca/infowast/watgreen/nativetrees.html (viewed 9 August 2003) (UW, comments on suitability)

City of Ottawa Forestry Service. Average urban tolerance of trees in Ottawa. Ottawa: Ottawa Horticultural Society; 2003. Available at http://www.geocities.com/otthortsoc/urbantree.htm (viewed 9 August 2003) (salt tolerance: 1 = Very tolerant 2 = Tolerant 3 = Moderate 4 = Sensitive 5 = Very sensitive )

Layberry RA, Hall PW, Lafontaine JD. The butterflies of Canada. Toronto, Ont.: University of Toronto Press; 1998. (larval food sources)

Hanrahan C. Planting the urban landscape: selected trees and shrubs for birds. Trail & Landscape 2002;36(3):115_122. Available at www.achilles.net/ofnc/fletcher/howto/treesforbirds.php (last viewed 9 August 2003) (use of species by birds and mammals)

I also used these web sites, but am not so sure about the information. The first is rather sketchy; lots missing; the second looks good, but I don’t know who this person is or where he got the information.

http://www.evergreen.ca/nativeplants/

http://www.rook.org/earl/bwca/nature/trees/pinusstrob.html

Sandra Garland