Location:
The area chosen for study is located at 777 Oliver St. in Oak Bay, British Columbia. The area contains 3 closely linked micro ecosystems that are situated in an urban residential environment.
Oak Bay is in the Coastal Douglas fir biogeoclimatic zone. This zone is the most at risk zone in BC and it has the highest concentration of rare and endangered species in Canada (District of Oak Bay, 2014).
The first site visit occurred on the first day of spring (March 20, 2018) at approximately 1:00 pm. It was mostly sunny with a temperature of 10 degrees and light wind.
Site Details:
Two study area ecosystems are located in the front of the property. The rear study area is separated by the two in the front by a residential home. The study areas at the front of the property are West facing and end at the city street, which has a low volume of traffic. The total area of both is approximately 7 metres long by 11 metres wide, with each being about equal in size. This area is roughly split in half by a pathway that separates a predominately native plant garden from a typical grass lawn. The garden contains approximately 38 native and 9 non native plants, trees, and shrubs. Additional plants are assumed to be present below ground in a dormant stage. Both sides are contained by asphalt driveways.
The rear of the property is East facing and is approximately 14 metres wide by 24 metres long. It is primarily moss covered, with some remnant occurrences of non-native grass in the central location. One large Garry Oak tree is present, which dominates the area by crown cover. The moss/grass is contained by a small buffer on 3 sides consisting of spruce, birch, cedar, plum, ash (sapling to immature size) and low shrubs of wild rose, snowberry and others that appear to be non-native. The remaining side is contained by the rear of the house and a cement pad.
The overall topography of the entire site is flat, with a gentle slope of < 1 metre from the front of the property to the back. Early signs of leaf development on some trees and shrubs was present, while the remainder of species appeared to be dormant.
Purpose:
I am interested to see if there is any advantage to wildlife in an urban garden setting that is dominated with native plants. Two possible controls exist, with one being adjacent to the primarily native garden, which is a typical lawn ecosystem that is typical in the neighbourhood. A further control exists in the back yard, which is also fairly typical for the neighbourhood except that it is bordered on 3 sides by a large number of native plants and trees.
One concern is that the ecosystem in the back yard (containing roughly 20% native plant/tree cover compared to roughly 85% native plant cover in the front yard) will be over-represented with visits from wildlife or insects because it is not influenced by the pedestrian or vehicle traffic that the front yard receives.
A possible question to consider is the scale of the primarily native plant garden, which is quite small in comparison to the total property size. It is possible that it is too small and sub-optimally located for any measurable effect on wildlife or insects.
Aside from wildlife, including birds, it may be more suitable to focus the study on the activity of insects alone, which may be less affected by the location of the native plant garden. However, there have been previous wildlife observations that suggest it may be possible to observe wildlife visiting various parts of the property.
A possible complication is the seasonality. With the start of spring, it could be that more wildlife or insects appear throughout the study area and duration due to the changing season alone. It is my hope that the control of a non native grass lawn area adjacent to the primary interest of study -the native plant garden- will be sufficient to determine if the native plants are attracting more wildlife or insects.
I am also interested to see if the native plants self-reproduce and increase in abundance or if the non-native species reproduce and encroach on the native plant garden.
Reason for interest in the study / Possible outcome
When I bought my house, I dug up the front lawn and planted mostly native plants, except where a couple of existing ornamental plants/trees were established because it was my intention to increase habitat for local wildlife.
My current intention is to do the same to the remaining land on the property. The removal of non-native species is a future consideration.
I am interested to know if there is any measurable effect on having a native plant garden at this current size and condition, which is less than 2 years old. A previous study that is related showed that insect activity was not increased by small scale additions of native plants and that they in fact preferred non-native plants (Matteson, K. C., 2011).
Having a similar study area, I am curious to see if there is a similar effect in the region where I am located, which is different from the study area that Matteson looked at. If there are significant observations that wildlife or insects prefer the non-native species which are present, I would consider keeping them for that value and re-cosnider an all native plant garden for the rest of the property.
References:
District of Oak Bay, 2014. District of Oak Bay Official Community Plan. Retrieved from: [https://www.oakbay.ca/sites/default/files/ocp/2014/OakBay-OCP-Final-Website-dec0414.pdf]on March 21, 2018.
MATTESON, K. C., & LANGELLOTTO, G. A. (2011). Small scale additions of native plants fail to increase beneficial insect richness in urban gardens. Insect Conservation and Diversity, 4(2), 89-98. 10.1111/j.1752-4598.2010.00103.x
