|November 02, 2011|
The Vancouver Convention Centre: Six-Acre Living Roof Now A Thriving Ecosystem
|It's been a record-breaking year for the Vancouver Convention Centre in more ways than one. Apart from being the most successful convention year ever, the Centre's six-acre living roof -- which is getting its annual trim this week -- has had an unprecedented year of growth. |
"We're excited to see that the living roof is truly flourishing in a short span of three years; and what's more, doing what it was intended to do," said Bruce Hemstock, landscape architect of the Vancouver Convention Centre's living roof and partner at PWL Partnership Landscape Architects Inc. "The growing condition on top of the convention centre is very well suited for the planted coastal plants and grasses. The aster, in particular this year, is thriving beyond our wildest imagination with some up to eight feet tall. It provides the rooftop honeybees with an incredible source of food."
The bees living in the four beehives on the roof have produced approximately 120 pounds of wildflower honey this year. Recently harvested from the hives, half of the honey will be used by the culinary team for exclusive treats and pastries, while the rest was put in jars for promotional use.
"Apart from strong growth of the plants and grasses, the roof has become an ideal natural habitat for wildlife. This year, we've seen a diverse insect population and song birds that have made their way back into the downtown core," added Hemstock. "I anticipate we'll see a greater variety of wildlife and continued biodiversity of the roof in the future."
Insects observed on the roof include ants, spiders, dragonflies, grasshoppers and damselflies. Birds observed include a variety of sparrows, juncos and finches. Brought in by both birds and the wind, new plant species have made the roof their home, adding to the diversity of the rooftop ecosystem.
The mowing of the living roof -- the only formal trimming it receives annually -- takes a crew of up to six landscapers at any given time. With no chemical fertilizers, pesticides or herbicides used, majority of the clippings will be left on the roof to be composted back into the soil as fertilizer.
The Vancouver Convention Centre's living roof is the largest in Canada and the largest non-industrial green roof in North America. It is landscaped with more than 400,000 indigenous plants and grasses from 25 different species of the Pacific Northwest. The facility's sophisticated black water treatment plant collects and cleans water from washrooms for use in the living roof irrigation system in the summer. The living roof also acts as an insulator, reducing heat gains in the summer and heat losses in the winter.