On the forest floor of Mount Douglas Park, a thick mess of tangled English ivy meets raw dirt. In Saanich’s largest urban forest, this is the battle line against an invading nutrient thief.
It’s a rainy morning in the park as Dick Battles and Dave Poje don gloves and florescent yellow volunteer shirts, and pull ivy by hand, yanking out endless threads of green until only earth remains. Ivy roots are shallow, but it moves fast and smothers everything in its path, including the trunks of Douglas firs.
“This is the worst island (of ivy) I’ve ever seen. It’s ideal growing area – flat and wet,” Poje remarks. “The problem is here that the ivy weaves together and is a carpet in every sense of the word. It’s very, very difficult when its interlaced.”
Battles and Poje, two veterans of invasive species eradication in Mount Douglas, are part of a small crew of core volunteers systematically ridding the forest of ivy and its prickly invasive brother, English holly. Scores of volunteer groups under Saanich’s “Pulling Together” program log thousands of hours each year pulling untold tons of biomass from Saanich parks.
At Mount Doug, progress is evident. On the east side of Glendenning trail, long strings of dead ivy rot on tree trunks in cleared zones, and ferns and salals have taken root on the floor. A wedge of forest cut by Mercer trail is 100 per cent ivy free, an area that should see native plants repopulate the area in a year or two.
Poje estimates the volunteer crews have cleared 170 acres out of 450 in the park over the years.
“You can walk from the west boundary to the east boundary and not hit invasive species. That’s huge. It’s starting to be noticed and visible,” Poje says. “It’s amazing the progress we can make through here.”
Cory Manton, manager of urban forestry and natural areas for Saanich parks, points out forest paths are lines of control. A few metres away on the east side of Mercer, carpets of ivy choke out native plants and competes with trees for nutrients, water and light.
“Once it climbs in its mature form, ivy can kill. You see trees engulfed in ivy,” Manton says. “Ivy blocks photosynthesis, and limbs die off. It feeds into the tree through the bark.”
Invasive plants are enough of a problem that Saanich has three staff dedicated to guiding and assisting volunteers, and monitoring invasives that have gained a foothold throughout the community. Manton said they’ve adopted an “early detection, rapid response” protocol to control relatively new invaders. Garlic mustard, for one, started sweeping through Mount Doug five years ago.
“There were hundreds of bags (of garlic mustard) in the first season. Now it’s four or five. We’ve stopped the spread. There’s no seed source so in this park and it’s under control, but there are another dozen sites in Saanich,” Manton says.
Saanich parks has eight priority invasive species to control, with enemy No. 1 being knotweed. Bamboo-like, knotweed spreads and grows like a proverbial weed and was originally introduced to Victoria by horticulturalists. Unlike holly, ivy, or broom, knotweed is controlled through herbicides and isn’t yet beyond total eradication.
“If you try to dig (knotweed) out and leave any in the ground, allows it to spread and move. The roots go deep. It’s very destructive. In England it has impacted property values,” Manton says. “Some species you can pull out of the ground, sometimes the soil disturbance makes the problem worse if a seed bank explodes.”
Saanich takes its cues from the provincial invasive species strategy, and works with the Vancouver Island Coastal Invasive Species Committee, and the Capital Region Invasive Species Partnership (CRISP), a collaboration between Victoria, Saanich and the CRD started in 2010. It’s a lot of people and resources dedicated to invasive management, which is a fundamental shift in thinking from a few decades ago.
“In the old days there wasn’t a lot of focus on natural parks. The ideology of the day was that parks can take care of themselves,” Manton says. “We’ve learned a lot over the last decade. We’ve got to manage the forests and get the invasives out, or you’ll get a complete monoculture of invasives.”
Ad-hoc volunteer groups have worked on controlling Scotch broom, blackberry and ivy in Saanich for decades, and the municipality has had invasive species control on its radar since the early 2000s, but it rolled out an official management strategy in 2011.
By organizing and funding volunteer groups, and figuring out how to control invading species, Saanich is trying to take a leadership role in a region besieged with invasive plants and animals.
“Invasives know no border. If it’s in Oak Bay it will come into Saanich. If it’s in Central Saanich it will come into Saanich,” Manton says. “The Capital Region has the most diversity of invasives because of its climate.”
On this rainy day, Poje and Battles will put in about two hours of labour pulling ivy in Mount Doug. Progress is slow and steady, and both retired men say they can’t think about the vast number of hectares yet to be cleared. It’s one day at a time, one plant at a time.
“I live nearby. For me it’s personal. I want to be in the woods and this is part of my lifestyle now,” Battles says. “I’m out here six or seven days a week, a couple hours per day. It’s my volunteer effort for the community … I love to be here and I love the park. To me it’s a second home.”
“This is a huge task, but you can’t think about the task,” Poje adds. “I don’t know if we’ll ever get finished, or if somebody will replace us, or if in 30 or 40 years it could go back (to ivy). We will just keeping doing our best for Mother Nature.”
For more on Saanich’s invasive species management strategy or the Pulling Together volunteer program, see saanich.ca/parkrec/parks/natural.