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Guardians at the gate

The Sea to Sky Invasive Species Council has evolved from a grassroots weed-puller to an agent of ecological restoration.

On a late July morning, high on a hillside above Britannia Beach, the view across Howe Sound is nothing short of spectacular. Hanging in a cloudless sky, sun infuses an ocean turquoised by snowmelt and glacier flour brought down in the latest heat wave. Today looks to be yet another smoker, and deep within a massive stand of knotweed, Rob Hughes is already sweating.

Wielding large machetes amidst the woody, leaf-heavy, three-metre stems, Rob and Breanne Johnson, who comprise one of the Sea to Sky Invasive Species Council's two field crews, are busy knocking knotweed over to make it easier to spray. I'd already learned enough about this plant in previous outings to see why it was a focus of the SSISC's control work and such a problem here: the knotweed had claimed considerable ground on this dead-end street, pushing up through gardens, lawns, gravel, driveways and anywhere that construction had taken place. It arrived in the neighbourhood along a BC Hydro right of way, following it along a row of houses to make incursions into every property. At the bottom of a steep backyard, Rob and Bre had crossed a fence-line, disappearing into a knot of knotweed that strained in every direction. Only now, an hour later, were their torsos emerging above the foliar fray.

PHOTO BY LESLIE ANTHONY - Sharon Watson treats some sneaky knotweed in Alpine neighbourhood, Whistler

A Lower Mainlander with a degree in ecology and environmental biology from UBC, this was Bre's first year on an SSISC crew. Prior to heading into the jungle she'd spent time carefully mixing chemicals and readying sprayers and injection guns. The guns deliver a preparation of 48 per cent glyphosate (an enzyme-inhibiting herbicide commercially known as Roundup) directly into stems while the leaf spray comprises the same chemical diluted to five per cent active ingredient and mixed with blue dye so you can see what's been sprayed. It takes a while to get equipment prepped and filled, but this is science, and, as in the lab, careful preparations are critical not only to protect the crew from the substances they handle, but to get things right: you want to kill as many plants as possible by the most efficacious means, and with the cost of chemicals, you don't want to be spraying money indiscriminately. Actually, you don't want to be spraying at all if you can help it, which is why guns are used to directly inject the chemical in larger stems. Sometimes, however, as now, a patch is so large and dense it's done in stages, starting with knock-and-spray followed by stem injection later in the summer when the plant is winding down metabolically and sending most of its energy — along with the glyphosate — to the considerable root system; the plant then dies over the fall and winter. The job on this particular street was more complicated: the crew was here to take knotweed out of a few private yards, where only injection could be used because of pets and children. But the ultimate source of that knotweed was over the fence in the right of way, hence the jungle warfare overture.

Every time Rob emerges he looks as if he just went for a dunk. This is hot work. Tough work. And potentially depressing when you lavish this much effort on a patch of knotweed that's surrounded, as here, not simply by other patches but by what may be parts of the same individual super-organism which, when you look either direction down the right-of-way, stretches as far as the eye can see. Even Sisyphus would have quit by now.

PHOTO BY LESLIE ANTHONY - SSISC crew worker (background) and Hogweed (foreground) in Britannia Beach

"I try to keep focused on the long term," says Rob, a veteran SSISC crew supervisor with forestry experience. "This guy is paying to have his yard cleared. He's making an effort. So maybe the people who don't want it done will see the results and buy in at some point. Sure it seems like an uphill battle — we're working on the outside, the perimeters of the problem, not the inside. But more people are getting on board. Last year the District of Squamish was behind us with very little funding, but after we did a small project for them they really came on board this year. So, little by little."

An aggressive semi-woody perennial native to eastern Asia, Japanese, Himalayan and giant knotweeds were variously introduced in the 1800s to both the U.K. and North America as ornamentals and (ironically) for erosion control. Often mistaken for bamboo, they're easily distinguished by broader leaves and a more vigorous root system. Persistent and incredibly difficult to control once established, knotweed presents the perfect ecological storm: it spreads quickly by both vegetative (rhizome and plant fragment) and, in some cases, sexual (seed) means; it creates dense thickets that degrade wildlife habitat; it reduces plant biodiversity by physically and chemically impeding native vegetation; and it moves down hills and along rivers by destabilizing slopes and banks with probing, non-filamentous roots that can break off to slide or float away and establish new populations. And both Squamish and Britannia are lousy with the stuff.

I leave Rob and Bre and head south past the Gallileo Coffee Company to where another SSISC veteran, Sharon Watson, whose degree is in environmental science, is working with rookie Sam Cousins, a GIS geographer by training. They've parked by the highway in front of a large aggregate pit to check what's left of a dense knotweed stand sprayed last year. The dry husks of plants crunch underfoot like old cornstalks. Here and there new eruptions flare like small brush fires, and are similarly snuffed out by Sam and Sharon with spray bottles of glyphosate. Ding dong the knotweed's dead: now what? Well, if you can't rehabilitate a site after eradicating (and almost invariably no one wants to pay for this) usually more invasives; in fact, one grey pile of old knotweed debris looks like an invasive salad, crowned in small clumps of alien thistle, burdock, comfrey, and fox glove. And all around tall, dense swaths of Scotch broom encroach, an invasive that matches knotweed for persistence and difficulty of control for entirely different reasons: with roots like anchors, prodigious seeds that can last 80 years and require disturbance to germinate, pulling or digging up a plant basically reboots the infestation. If it weren't for the few native conifers, alders and aspens in the background here it would be a totally alien landscape.

PHOTO BY LESLIE ANTHONY - Sam Cousins loads up a stem-injection gun with glyphosate

"Now here's a good example of a jurisdictional problem: MOT is a partner and this is MOT land we're working on. But over there..." says Sharon, gesturing into the line of trees separating us from the pit, "it's private. And knotweed doesn't know the difference."

Of course. Fortunately the landowner — a wealthy developer — allows the SSISC access to control invasives though it has chosen not to fund the work, nor do any follow-up on its own dime. Hence the constant eruptions of knotweed along the property's frontage, source populations for further spread. It's like putting out the main body of a wildfire but leaving the edges to smolder: eventually the sparks will blow back into a full-blown conflagration. This places the SSISC between a rock and a hard place: though they won't be paid for it they must utilize the opportunity of control in the pit as insurance against the considerable labour capital invested along the highway. Even then, in the end it might all be for naught. In August an MOT crew will knowingly mow the roadside for parking-lot sightlines prior to the Squamish music festival, sending knotweed fragments, some living, flying in a hundred directions.

It's such scenarios that now see knotweed leap-frogging up and down Highway 99 like a silent green monster — an unwelcome intruder, a burglar of garden space, an underground iceberg, a Little Shop of Horrors, a plant that invites analogies the way conservatives invite condemnation: through their very existence.

PHOTO BY LESLIE ANTHONY - Bohemian knotweed

If knotweed deserves any grudging admiration it would be for exuberance. Where most other plants have a familiar shape to which they aspire — the lollipop of hardwoods, the spear-point of conifers, the fan of ferns — knotweed appears to stretch in every direction simultaneously, occupying maximum airspace leaf-by-offset-leaf, blocking out other plants (even ever-tenacious Himalayan blackberry) and reflecting that vigour, more perniciously, underground, such that scions of the evil mothership — cleverly disguised as apparently unrelated, rubicund sprites — pop up like a ring of remote mushrooms metres away. In only a few years a single knotweed plant obtains Brobdingnagian proportions, breaking through surrounding roadways, building foundations, electrical substations, and destabilizing the ground to move itself around. In this it seems to transcend the typically sessile nature of plants to the point of animation. But let's not grant it so much — excuse the pun — ground. Step back a bit to imagine the fragment from which this mass first erupted, perhaps as small as 0.8 grams, the size of a fingernail, expanding in time-lapse. Put that way, a knotweed infestation can only be seen one way: as a slow-motion explosion, a chlorophyll Big Bang. The very essence of the militaristic lexicon erected to describe invasive, alien species.

In his 1998 essay "Planet of Weeds", author David Quammen made a prescient observation regarding the human-propelled Sixth Great Extinction currently sweeping species from the Earth at a rate unseen since the disappearance of the dinosaurs: "Fifth of the five factors contributing to our current experiment in mass extinction (is the problem of invasive species). That factor even more than habitat destruction and fragmentation, is a symptom of modernity. Maybe you haven't heard much about invasive species, but in coming years you will."


We have. Alien invasive species now make daily news around the globe as they topple native ecosystems and threaten human health, safety, food and lifestyle. Water hyacinth, Asian carp, Burmese python, West Nile virus; stories that range from humorous and cautionary to disturbing and frightening. Man vs. Nature in a battle of our own creation — and, increasingly, our undoing.

Some of this, of course, isn't news. Since the earliest days of trade and travel, the introduction of non-native species on foreign shores has been a problem. Many introductions involved livestock or pets that escaped human control to establish feral populations, which subsequently spread unchecked to destroy native communities of plants and animals. Other introductions involved the surreptitious baggage of human occupation (e.g., rats, cockroaches, dandelions); commerce (e.g., weevils, beetles, Zebra mussels); the flora and fauna of a native land (British emigres have willfully seeded most continents with the nuisance of rabbits, magpies, sparrows and an array of quaintly obnoxious garden plants); wishful food sources (red deer, Nile perch, bullfrog); failed pest control (cane toads, Indian mongoose, mynah bird); and myriad diseases plus their vectors (malarial mosquitoes, Dutch elm, chytrid fungus).

The current global proliferation of invasive alien species is so pervasive as to be nothing short of a re-imagining of the planet's surface. Most ecosystems surrounding us — the ones we call home, that we imprint on and enjoy, that we speak glowingly of to others, that we largely take for granted — are, in fact, not what they seem. They are instead reservoirs for myriad aliens, even if we cannot see them or readily identify the ones we do see. Worse, some interlopers are spreading in unprecedented ways, even in the lush and quintessentially Pacific Northwest ecosystems of the Sea to Sky corridor. Which is where folks like Bre and Rob and Sharon and Sam come in.

PHOTO BY LESLIE ANTHONY - Scotch broom looks lovely for a few weeks — just enough for people to let it into their lives

The SSISC was co-founded in July 2009 by Whistler Naturalist honcho Bob Brett and Stewardship Pemberton's Dawn Johnson. "After five years of the Whistler Biodiversity Project we were finding invasives in almost every species group — things transported with nursery stock like slugs, snails, earthworms, mosses, fungus and plants — so it made sense to do something in the area of prevention," says Brett.

When the original coordinator, Stewardship Pemberton's Veronica Woodruff, stepped aside for maternity reasons, Whistler Naturalists' Kristina Swerhun, with an MSc in climate change impacts on alpine biodiversity, took over. "My first task was filing the papers to create a non-profit and it just kept going from there," recalls Swerhun.

What "kept going" means was working as director for four years, raising awareness of alien invasive species among public, government and industry in the corridor with a successful "spotters" program, improved communication among a diverse set of stakeholders, annual improved funding, successful fieldwork highlighted by treatment of all known sites of noxious giant hogweed (whose sap can cause dangerous burns) as well as the most northerly knotweed sites on public land along Highway 99 in the canyon (you've no doubt seen the yellow roadside signs serving the dual purpose of public awareness and a warning to road crews not to mow). More importantly, the SSISC became an official source of expertise supporting land owners/managers in identification, prevention, and control efforts, delivering comprehensive mapping of invasive plants and prioritization of control sites, and aiding formulation of the RMOW's new invasive plant bylaw and similar legislation being looked at by other governments.

PHOTO BY LESLIE ANTHONY - Orange hawkweed, Pinecrest area, old Hwy 99 route

A key tenet for Kristina was building the capacity of stakeholder groups so that best practices for invasive species were part of their everyday operations, which helps limited budgets go further. "It could be discouraging at times, especially when there was so much you wanted to do but didn't have capacity for, so picking battles was key; you had to accept you couldn't do everything and focus on programs with a high probability of success," recalls Swerhun. "It was helpful that SSISC directors and advisors — a diverse group of educated and dedicated people — met regularly to set priorities. Before I left, SSISC received charitable status and found a great new executive director in Clare O'Brien."

A biologist specializing in predator-prey interactions, Clare previously did modelling and predictive range mapping for invasives with the parks department of New South Wales in Australia: fox and feral cat control, goats and pigs and a little bit of plant work. After some GIS work for Enivornment Canada in Delta, she'd started her own contract-based mapping company when the SSISC executive director position opened up.

She jumped in, with support from 17 other invasive species groups in B.C. helping show her the ropes over the fall and winter. Despite the coup of attracting enough funding to run two field crews this summer, the challenge of comprehensive partnerships and buy-in across the region immediately made itself apparent. While Whistler, District of Squamish and other entities provide funding for the SSISC, the Village of Pemberton and larger SLRD bring no money to the table, despite the importance of linking all jurisdictions across a region. "Funding is tied to what funders want to achieve in the short term with specific taxa, so that makes long-term planning for multiple species difficult. With general funding we could strategize better, then source specific funding for priorities. Right now it's the other way around. In order for invasive plant management to work, every jursidiction has to be involved in a similar functional capacity, leaving private land as the only wild card."

PHOTO BY LESLIE ANTHONY - If you think you've been seeing more of this flagging around, you are correct.

Whether the battle is with knotweed infestation or jurisdictional issues, isn't this a bit of David vs. Goliath? "Yes, sometimes," agrees Clare. "It's a huge, non-stop battle. But everyone agrees you can't just do nothing. So we're trying to use the resources we have in the best way possible. We're focused on early detection and rapid response for new infestations as opposed to longstanding ones, which is pretty much the invasive species management norm."

If putting out brushfires while the planet burns is the norm, why care at all? "Because costs go up," answers Clare. "The costs of damage to ecosystems and infrastructure skyrocket once prevention fails, so the cost of doing nothing is far greater than the cost of doing something. Strategic control is about retaining values. You might not be able to control burdock or orange hawkweed along Highway 99 in Whistler Valley, but if it gets into the alpine you're going to eradicate it to protect native wildflowers."

Paul Beswetherick, Landscape Maintenance Supervisor for the RMOW, an SSISC board member from the start and its current chair, agrees. "The muni always kept an eye on what was happening in the corridor. It was important to track what was coming in and how it might threaten the environment and our maintained landscapes. (SSISC) has always focused on the operational side and so it has had a significant impact on stopping the spread of invasives in a very short time because it's action-oriented. It has been very effective and tremendously efficient in using limited funds to stop invasions."

Paul also sees the RMOW's new invasive species laws as a significant step. "They're forward thinking, proactive, and the legal requirement for landowners to deal with invasives will push those on the fence to say 'this is the right thing to do.' Still, a fine is a last resort. Swinging a hammer never wins you any friends so we'd rather educate landowners to act. When something is illegal, however, it creates a whole new impetus to take it seriously. By-laws mean buy-in. In that sense Whistler is ahead of the game."

PHOTO BY LESLIE ANTHONY - Applying herbicide

Clare sees Whistler ahead of the game in other ways as well. "Because we don't have much of the dangerous stuff like hogweed or knotweed in Whistler we're able to focus on things that are lower priorities eleswhere and stop them from getting a foothold here."

In that respect local landscape companies are pitching in, reporting invasives and, where approriate, removing them. SSISC runs information workshops and provides certification for landscapers, earthmoving companies, and environmental consultants, disseminating skills and knowledge to increase the number of eyes on the ground. Particularly for private land: contractors are the best means of convincing a contractee that removal is in their best interest. And while Whistler might be out front when it comes to knotweed (very few occurrences) and Scotch broom (the SSISC maintains a zero-tolerance control line north of Brackendale) unfortunately, it's too late for Squamish and Britannia.

A former mining community, copper was extracted in Britannia until 1974; despite the riches spirited away, decades of contamination fouled the land, creeks and surrounding ocean bottom, creating one of the most contaminated places in all of B.C.. When the mine shuttered the community fell into disrepair; despite artisan studios and gift shops, it remained a blight on the drive between Vancouver and Squamish. Much of the area was reclaimed in recent years, and the mine turned into a museum to catch tourist dollars flowing up the highway during the 2010 Winter Olympic Games. While immediately adjacent tailings areas remain devoid of vegetation due to heavy metals in the surface soil, in other places greenery has crept back in. Few of these colonizers, early adapters, and pollution-tolerant plants, however, are native. Compounding this alien welcome mat, rehabilitation included trucking in fill from the lower mainland, none of which was screened and, as is now apparent, included a litany of invasive hitchhikers.

PHOTO BY LESLIE ANTHONY - The mucky work of cleaning yellow-flag iris out of a ditch. Location: hwy 99 in front of Rimrock Hotel, Whistler

Back in Britannia, an after-lunch giant hogweed hunt is an entirely different animal than the morning's knotweed struggle. Higher on the hillside, past a benchland overlook where monster homes are being constructed after a rock-bottom land grab by developers, we park in front of low bungalows and triple-wides that were clearly part of the original mine community. Behind them we find hogweed growing in the corner where no fewer than five backyards converge. Some of the plants have been cut down, doused in gas, and placed under tarps (not advisable); others have been cut and left on the ground (ditto); other small ones are still growing through lawns, gardens and compost. Rob sets to digging up and/or spraying what's left, the plants small enough that it doesn't require donning a full-body HAZMAT suit as would otherwise be the case. Soon he's done and it's time to go home. While the satisfaction in ferreting out and removing a dangerous plant like giant hogweed is clearly higher than endless knotweed control, the field crew all express both an affinity for the work (Rob — "we've had some great successes," Sharon — "I like having an impact on the environment," Bre — "it's a trend in ecology that's easy for people to understand," Sam — "great outside job with a small team; manual removals like yellow-flag iris in Whistler are great") and worries/difficulties (Rob — "CN didn't pay us for last year and isn't returning our calls," Sharon — "the long-term effects of pesticide exposure," Bre — "it can be super frustrating," Sam — "if everyone in the corridor was on the same page how much more could we get done?"). So goes the yin-yang world of invasive biology.

For me, the day has been fascinating and horrifying in equal measure; when you invest any thinking in the potential of invasive plants like knotweed, it becomes an exercise in infinitude akin to contemplating deep time or staring into the firmament, enumerating stars and trying to divine the depth and vastness of the universe: there is literally no place for the mind to stop.

It has also changed my view of where I live. On my way north from Britannia, where once I saw only greenery, I now see endless stands of broom and the sterile beast of knotweed. It's pretty obvious that the lines they trace on the landscape — along road, rail, and hydro right-of-ways, ditches, parks and field — are in fact lines drawn by ourselves. It brings to mind something Rob mentioned earlier in the day, when he emerged dripping from the first stand he'd treated. "Once knotweed has a route of distribution it doesn't take much for it to take off... but disturbance is the key to getting it started."

PHOTO BY LESLIE ANTHONY - Breanne Johnson enters data at a hogweed infestation in Britannia Beach

I look left across the aquamarine waters of Howe Sound shimmering in the summer sun, an idyll only now just recovering from the excesses of the mining and pulp-and-paper industries that did it in. Whales and dolphins are back; people are harvesting shellfish. But on the far shore, a mere wind gust away from the folly/fiasco of Britannia and Squamish, I see new clearances for LNG terminals, clear-cut logging marching up mountainsides, and slashes across the mountains at all altitudes to accommodate transmission lines from myriad IPPs. In essence, a diorama of disturbance — the promised land for a new wave of aliens.

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