Trees! Glorious Trees!
Fortunately for us, the streets are really green in this city. And I don’t just mean the mentality of the masses. Between the parliament buildings, cobbled Government Street, horse carriages, and the entire neighbourhood of Oak Bay, Victoria has always been considered a Little London of sorts – much to the chagrin of the young locals striving to define this city as anything other than the City of Gardens (those hanging baskets will be the death of me).
One aspect of this city where the newlyweds and nearly-deads do find common ground is our love for the amount of greenery or tree cover lining our streets and shading our backyards. We seem to keep our urban foliage close to our hearts, but overall Victoria is no poster child for protecting natural areas with ecological value.
A recent study commissioned by a local environmental non-profit has had a lot of press coverage in Victoria (Times Colonist, Metro News, Victoria News, Chek News, CBC Radio). This is likely because of this shared interest in greenery between millennial environmentalists and centenarian traditionalists that make up most of the city. The study is a map (yes!) of the Capital Regional District looking at land cover from 2005 to 2011, which includes tree cover but also impervious surfaces, exposed soil and agricultural fields.
My apologies in advance to those who are R/G colourblind, this is not a good scheme for you. I will change this and re-post again. For now, this is an image of 2005 land cover (left) and 2011 land cover (right) around Langford Lake. The red is impervious surface/buildings, grey is exposed soil, green is tree cover, yellow is grass.
It is clear to me in this image that there has been a relative increase in impervious surfaces in the form of development, some on exposed soil, some on tree cover.
The spatial analysis of one hectare grid cells with six classes of percent tree cover. Those cell classified as total tree cover can be anything greater than 75% tree cover. The result indicated that the three higher density classes (>25%-100% tree cover) are all decreasing while the three lower density classes (0% to 25% tree cover) are all increasing.
In other words, we are losing areas of high density forest and gaining low to no density forest.
Although the media preferred to make this more of a blame game for the biggest loser of all municipalities (“Saanich lost the most treed land over the six-year period: 378 hectares, equivalent to 146 of the University of Victoria’s Finnerty Gardens” Times Colonist), there is a lot of interesting information to be gathered from this data (not to mention their method of classification had an impressive 94% accuracy after field testing)…
One of the more intriguing aspects in the full report of this study is the inclusion of all First Nation Reserves in the CRD, which went completely unmentioned in the media. It was also interesting to find that for the entire region, the decline of exposed soil/rock (-1.5%) is close to the decline in tree cover (2%). Another interesting factor to look at would be the agricultural fields in terms of food security and production: have they increased or decreased? Are they replacing high density forest? Are they being replaced by impervious surfaces?
This looks as though it will be the source data for a number of projects across the region. Very exciting!
Here’s an image of the view from Mount Finlayson – a recent development that is visible from the land cover mapping analysis completed between 2005 and 2011.
It is a big development but these were not the primary source of tree cover loss. Read the report to find out more! I hope that this report will empower the community to request their local municipality strengthen the tree protection bylaws and provincial government reinstate a parks acquisition fund. Oh, and support the local land trusts in the meantime.


















