Landscape Architect Quarterly Features Trees: Myths, Debates, and Some Truths Round Table Keeping Urban Forests Growing Spring 2

Landscape Architect Quarterly

10/ Features Trees: Myths, Debates, and Some Truths

22/ Round Table Keeping Urban Forests Growing Publication # 40026106 Spring 2009

Messages .05 03

Letters to the Editor President’s Message The Up Front item on cemeteries [Ground 04] covers an imagina- It has been said that anyone who has planted a tree is an opti- tive idea from Veronica Schroeder to relieve growing pressures mist. If so, then our profession must be the most optimistic of all, for space in urban areas by using green roofs for cemeteries. since landscape architects have collectively planned for and been However, I couldn’t help but be a little dismayed by the opening instrumental in the planting of several hundred thousand trees in line of the piece, “ When I see a cemetery, I see a huge expanse the past few years. of land that could be used for other things...” Many cemeteries are enjoyed by people for walking, researching, and enjoyment of Our association can be compared to a hardy oak tree. Our green settings. If a major green space, whether a cemetery, an roots—laid down by the founders of the OALA more than forty undevelopable ravine, even a golf course, does no more than fill years ago—are solid, and our sturdy trunk holds up a wide, our passing eye with nature, it performs a valuable service. over-arching canopy. Our bylaws and regulations provide a secure structural framework for our association to flourish and be So while Schroeder’s idea has merit, perhaps we could also represented by members from a wide diversity of specialties, consider ways to make existing cemeteries all the more accessi- which collectively represent landscape architecture. ble and useable while still protecting their existence simply as green oases. Our profession is properly poised to meet the challenges of our present global economic crisis. These emanate from various The Up Front item on the University of Guelph archives [Ground 04] circumstances, but I believe the most lasting impact will be led by was a nice reminder about the collection. Any merit in focusing on landscape architects in prominent roles developing green, one or two aspects of the collection as a regular feature, with sustainable solutions for our communities. enough of their graphics to tell stories about their contributions? The demographics of the OALA are set to change over the next The Round Table in Ground 04 was a nice start on seeing our- few years as many of our leaders retire from active work. This will selves as others do, a useful tool in diagnosis. Philip Weinstein provide new opportunities for our associates and new members commented about his old partners’ opposing attitudes: one said to thrive in their careers. I am optimistic that the future of the OALA invisibility was good, the other not. Since I am the person who, is bright. Our core is strong, our growth is vigorous, and the call for several decades ago, said to Philip that invisibility was okay, I our profession to take up leadership roles in strategic planning would like to clarify. Landscape architecture is a broad field, and and design has never been so clear. sometimes a work of landscape architecture is successful because it enhances without standing out as an intervention. This is my last Ground message as OALA President. It has been an While such an attitude may not be unique to landscape architec- honour to serve you as President during the past two years. I ture, I suspect it is more prevalent than in some design profes- encourage each member to take the opportunity to participate on sions and perhaps this provides a clue about our nature. Council. It is a rewarding experience to work and learn with our

BRAD JOHNSON colleagues and to understand and resolve the issues that confront OALA (EMERITUS), FCSLA, RCA our association on a regular basis.

I must congratulate the Editorial Board on the OALA landmark I look forward to meeting many of you at the 2009 CSLA/AAPC magazine Ground: Landscape Architect Quarterly, an aesthetic and Congress, in Toronto, hosted by the OALA. The theme, PERSPEC- content-rich quarterly for the landscape architecture profession. TIVES – 360˚ on 75, will celebrate the impact of the Canadian Landscape architecture is my second career. With fifteen years of Society of Landscape Architects over the past seventy-five years. marketing communications, advertising, and publishing stints in my Make your plans to participate, from August 13-15, 2009! former work life, I must say that this is a professional magazine. ARNIS BUDREVICS, OALA PRESIDENT I enjoy reading every issue, including the advertisements. [email protected]

JOSEPH YU, OALA HAMILTON

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other than grass is actually growing. We’re overlooking the Humber River, with one of the best panoramic views the city has to offer, yet to access the nature trails we have to clamber over a breach in the fence. The original design intent of this 0A particular housing model—”towers in a park,” says Stewart—is clear, yet some- 01 URBAN RENEWAL towers in a park thing has just as clearly gone wrong.

The reigning orthodoxy identifies Toronto’s Stewart is on a mission to rejuvenate the extensive ravine system as the feature that city’s tower neighbourhoods and, for him, makes the city unique. Graeme Stewart of the landscape is crucial. “Landscape- E.R.A. Architects Inc. posits a radical, myth- based changes could have a huge busting alternative. According to Stewart, impact,” he enthuses, listing everything what makes Toronto distinctive is that it is from simple fixes (“removing some a city of towers. With more than 1,000 fences”) to more committed research stud- high-rise concrete residential buildings ies (“solar analyses of sites to see where (approximately 25 percent of the city’s community gardens could go”). “So much housing stock), the Toronto area contains of this is about engaging open space,” North America’s second-highest concen- he says. tration of high-rise buildings, many of them built in the 1960s and 1970s. A fur- Stewart has championed renewal ther unique feature is that, unlike most schemes that include building over- other cities, these modern towers are dot- cladding (currently under development at ted in high-density pockets throughout the the University of Toronto by Professor Ted city and its suburbs, not just downtown: Kesik), so that buildings would become far “Toronto may be the only city where the jux- more energy efficient, saving money and taposition of bungalows and concrete tow- 0B reducing their ecological footprint. His ers is the typical landscape,” says Stewart. 0A/ Some European cities, focus doesn’t end with architectural reno- such as Rotterdam, are rejuvenating their tower vation, however. He believes it is possible neighbourhoods. Due to zoning and density bylaws, these to create sustainable and vibrant neigh- IMAGE/ Graeme Stewart towers are often surrounded by large 0B/ A typical tower bourhoods using ideas like infill housing, landscape in Toronto, areas of open space, “a huge resource,” Weston Road district energy, new community facilities, says Stewart. However, just as many of the IMAGE/ Jesse Colin Jackson transit, pedestrian, and cycling connec- buildings are neglected and falling into tions, and urban agriculture. Integrated disrepair, so too is the open space often into the emerging regional transit, growth, underutilized and uninviting, largely rele- and climate change plans, and fueled by gated to surface parking and in many the remarkable cultural diversity within cases surrounded by chain-link fence. these neighbourhoods, Stewart sees the Up Front: rejuvenated tower communities as a type Touring a quintessential tower landscape of neighbourhood that will be uniquely in Toronto near Kipling and Steeles on a Torontonian. The challenge for local Information bleak November day with Stewart, these designers is to create new, vibrant, and lost opportunities are brought into sharp dynamic “complete communities” that focus. We’re in an area that’s home to respect the historical characteristics of the on the 13,000 people (a population density concrete towers in the park and respond comparable to the third largest city in to local needs. These communities can Manitoba), yet we see no one. We’re connect residents to the landscape while Ground standing on what was once some of the remaining affordable and diverse. best farmland in the province, yet nothing

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In recent months, the goal of rejuvenating SOIL Toronto’s tower neighbourhoods has 02 valuing the rhizosphere gained a lot of traction. Following an international tour of tower refurbishment sites, “As far as I’m concerned, if we’re going to Stewart was enlisted by the city to publish talk about trees,” says Michael Ormston- an “Opportunity Book,” and the city has Holloway, “the first thing we need to talk branded the project “Mayor’s Tower about is soil.” Trees are of passionate Renewal.” In September, City Council voted interest to Ormston-Holloway, a recent to re-examine its policies surrounding graduate of the University of Toronto apartment neighbourhoods in an effort to Master’s of Landscape Architecture pro- help them become more ecologically, gram now working at Michael Van socially, culturally, and economically sus- Valkenburgh Associates in New York. tainable. An office—Tower Renewal Office—has been established to coordi- Prior to studying landscape architecture, nate the initiative and is to report back to he obtained a B.Sc. in Plant Biology and a Council in March 2009. The province’s professional M.Sc. in Forest Ecology: “I Climate Change Secretariat is on board. thought that I was studying forests, but much to my surprise, my M.Sc. in Forest 0D Landscape architects are currently Ecology was virtually a degree in soil sci- any more honey locusts in Toronto,” he providing input into some of the open ence.” Now, he’s taking that same mes- says with a laugh. “There’s a much wider space resource systems associated with sage about the importance of soils to his palette we could be using.” Toronto’s concrete towers. Brendan work at a landscape architecture firm: “As Stewart, an MLA student at the University landscape architects, we need to direct Ormston-Holloway suggests that there is of California, Berkeley, is developing land- our attention below ground.” a simple question landscape architects scape strategies for tower renewal in his should ask themselves, and it’s a question thesis. “Engaging landscape architects in Ormston-Holloway believes that, for too that might seem somewhat odd coming this project is fundamental,” says Graeme long, landscape architecture has from someone steeped in forestry: “We Stewart, “and they need to be involved focussed on the two-dimensional linear can put a tree in the ground, but why are from the beginning. There is tremendous surface of the earth—”this is the dimen- we putting it there?” He suggests that opportunity for innovation.” sion we activate in our work,” he says. once people start considering the “why” “And we also leap into the fourth dimen- question and making choices based on a For more information on the tower renew- sion of time, with our phasing strategies, wider range of goals—say, choosing a al project, visit www.towerrenewal.ca and for example.” What’s often missing, he species not just for the aesthetics, but also www.towerrenewal.com. believes, is the third dimension—the rhi- for wildlife, for example—the benefits will

TEXT BY LORRAINE JOHNSON AND NETAMI STUART, BOTH OF zosphere. “This is the medium of growth,” magnify: “The idea of biomagnification of WHOM ARE MEMBERS OF THE GROUND EDITORIAL BOARD. he stresses, “and yet soil is probably the benefits is just a fancy way of expressing most under-appreciated natural resource the basic idea of ecology,” he notes. in the developed world.” “Everything is connected.”

TEXT BY LORRAINE JOHNSON, EDITOR OF GROUND AND A BOARD MEMBER OF LEAF (LOCAL ENHANCEMENT While he’s keenly interested in “getting AND APPRECIATION OF FORESTS). people to look down, to ask themselves, ‘what am I walking on,’” Ormston- 0C/ Currently underutilized green spaces Holloway is also looking up, to the trees. surrounding Toronto's residential towers For his work with Michael Van Valkenburgh represent a huge opportunity. IMAGE/ E.R.A. Architects Inc. Associates on the Lower Don Lands in 0D/ Michael Ormston-Holloway’s thesis poster, “Urban Ecologies as Toronto (“yes,” he says, “it’s a little strange Landscape Infrastructure”

that I’ve moved to New York to work on a IMAGE/ Michael Ormston-Holloway project in Toronto”), he’s involved with the urban forestry issues on the site, particularly as they relate to biodiversity. “We probably all agree that we don’t need

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SCHOOL GROUNDS 03 designing children’s spaces

The non-profit organization Evergreen has been at the forefront of school ground greening in Canada. Through research reports, grant programs, a regular 0F newsletter, and the publication of numer- dramatically in just one generation—as you’re four or five, man are you going to get ous how-to manuals and web resources, Collyer put it in his keynote presentation, hurt when you’re twenty-five!” Evergreen has both promoted and sup- “we’re witnessing the disappearance of ported the development of outdoor learn- free roaming in childhood.” Robin Moore, one of the world’s leading ing grounds for close to two decades. experts on kids and outdoor environ- According to Cam Collyer, Evergreen’s As children’s experience of the outdoors ments, stressed that while children now Director of Learning Grounds, the organi- shrinks, the school ground environment have “too much structure in their lives,” he zation has been involved with approxi- takes on added importance as a site of wasn’t advocating doing away with it alto- mately 3,000 schools over the years. engagement with nature and with play. gether: “Clarity of structure is important, “We’re at a moment in time when the but outdoor environments should have At a recent conference in Toronto, “All stakes are getting higher,” asserted structure and fluidity, so kids have options Hands in the Dirt,” Evergreen brought Collyer. “This is a public health issue.” for informal experience—the first step to together an international and local roster curiosity and wonder.” As examples, he of speakers—including landscape archi- One of the ironies of framing school pointed to the importance of designs that tect Margery Winkler of Ryerson University ground design in terms of health is that incorporate curved pathways (“so kids and University of Guelph professor Nate this can, in some circumstances, lead to have motivation to move”), variations in Perkins—to explore recent research relat- poorly designed school ground environ- topography (“a little hill goes a long way”), ed to the school ground environment and ments, according to many speakers at the and food plants (“landscapes that are to look at design issues in particular. conference. Citing the work of Danish pickable, tasteable, and suckable!”). designer Helle Nebelong, Collyer suggest- A thread tying all the presentations togeth- ed that the simplification and standardiza- Other design ideas included diversifying er and adding a measure of urgency to tion of outdoor environments can have surfaces, and incorporating multiple levels school ground design work was the notion negative implications for children: “It does- and small sanctuaries—“hideouts for kids, that childhood has changed. No longer do n’t prepare them for the world.” Showing a places adults can’t get to, are crucial.” parents send kids outside to play with an slide of a rock mountain surrounded by offhand “be home for dinner.” As recent asphalt in Oslo—and admitting that such a Putting forth many practical ideas, the con- research in Sheffield, England, has docu- play structure “pushes the boundaries for ference, at heart, had a hopeful message. mented, the range of unsupervised wan- most North Americans”—Collyer proposed As Collyer put it, “when you diversify the dering in children’s lives has decreased a rethinking of physical development: “Put landscape, you erase boredom.” risk in front of children and they learn.” That is, although it may seem counterintuitive, For more information on recent research some measure of risk can actually help into designing outdoor environments for children learn to negotiate and avoid even children, see www.childrenandnature.org bigger risks. “We’re curious beings,” or www.evergreen.ca.

emphasized Collyer. “Kids need to be TEXT BY LORRAINE JOHNSON, EDITOR OF GROUND. enticed and provoked and excited by their physical environment.” He pointed to the 0E/ Creative features engage children at Coombes elementary school in work of Berlin landscape architect Oliver Reading, England. Ginsberg, who builds on research done by IMAGE/ Cam Collyer the insurance industry, which found that 0F/ Rock mountain at Manglerud elementary school in Oslo there are in fact fewer accidents in “adven- IMAGE/ Cam Collyer ture playgrounds.” Likewise, presenter Sally 0G/ The Niagara Escarpment Commission recently approved Visual Assessment Kotsopoulos had a blunt warning about the Guidelines outlining standards for development. notion of risk that has dominated school IMAGE/ Niagara Escarpment Commission ground design: “If you don’t get hurt when 0E

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THE NIAGARA ESCARPMENT Process 04 visual assessment guidelines The first step in the process is to identify any concerns over a development propos- Designated a UNESCO World Biosphere al’s potential visual impact on the Reserve in 1990, Ontario’s Niagara Escarpment landscape. A development 0G Escarpment is an ancient landform recog- proposal may include residential and agri- Not all of the investigative methods out- nized for its diverse ecosystems, rich agricultural buildings, telecommunication tow- lined in the guidelines would necessarily cultural lands, breathtaking scenic vistas, ers, recreational facilities, residential wind be required for a given study. and exceptional outdoor recreational turbines, and utilities. The proposal may offerings such as hiking and skiing. also include site alteration such as the Assessing Impact on the Development in the Niagara Escarpment removal of vegetation within hedgerows, Escarpment Landscape Biosphere Reserve is guided by the tree stands, or parts of wooded areas. This part of a study addresses the impact Niagara Escarpment Plan (NEP), Canada’s Where visual impact is of concern, the of the physical changes on the visual, first large-scale environmental land use applicant is advised that a Visual landscape, and scenic resources of the plan. The NEP sets out land use designa- Assessment Study is required and recom- Escarpment environment. As the character tions, related permitted uses, and devel- mended study methods are outlined in of the landscape varies greatly throughout opment criteria to assess these uses. It keeping with the type of proposed devel- the NEP, the impact of development must also provides the framework for a string of opment. A Visual Assessment Study first be assessed in the context of the particu- more than 130 existing and proposed establishes a baseline for the existing con- lar landscape. The assessment must parks and open spaces linked by the ditions, and identifies the physical changes ensure the proposal is in keeping with the Bruce Trail, Canada’s oldest and longest in an accurate and objective manner. NEPDA, NEP, and approved policy papers continuous footpath. Subsequently, the impact of the change on as well as identify whether or not the The Niagara Escarpment Commission the Escarpment landscape and visual development would alter the results (NEC), an agency of Ontario’s Ministry of resources is assessed. Natural Resources, is the land use plan- reported in previous studies. ning agency responsible for overseeing The guidelines identify a series of stan- Review development in the Niagara Escarpment dard methods applied in preparing a Review of a Visual Assessment Study may Plan Area, which is a protected area Visual Assessment Study. All of the meth- result in the NEC requesting that the pro- under provincial legislation (The Niagara ods address the visibility of proposed built ponent alter the proposal to minimize or Escarpment Planning and Development form when viewed from public roads, pub- mitigate impact. If the proposal’s resulting Act—NEPDA). lic lands, and the Bruce Trail. Public lands impact is deemed acceptable to the NEC, The NEP is administered through a also include public waterways such as the proposal would be recommended for Development Permit system. The assess- Georgian Bay and Lake Ontario. ment of land use change requires compli- approval. Critical details derived from the Visual Assessment Study would be identi- ance with the environmental and visual The methods include: fied in the approval and/or implementa- policies of the Plan and Act. • Digital viewshed mapping to objectively tion process that follows. and accurately identify where proposed Purpose of Visual Assessment Guidelines structures or built form would be visible The NEC’s Visual Assessment Guidelines The Niagara Escarpment Commission’s from public roads, public lands, and the and supplementary policy reports are planning process incorporates visual and Bruce Trail. The specifics of a proposal available at www.escarpment.org. scenic considerations; impacts on scenic will dictate the distance out from the vistas and landscape quality are consid- TEXT BY LISA LAFLAMME, OALA, A LANDSCAPE ARCHITECT WITH structure to be mapped—generally THE NIAGARA ESCARPMENT COMMISSION. ered alongside a range of other potential five kilometres. environmental impacts. Visual assessment studies help NEC planning staff identify • Where the viewshed model indicates and evaluate whether a development the development would be visible, proposal is compatible with the NEPDA specific viewpoints/viewsheds are and the NEP. In July of 2008 the NEC selected for additional investigation. approved Visual Assessment Guidelines This study component may include outlining standards for the preparation of line of sight cross-sections, studies, when required, in support of a photographic simulations, and proposed development. detailed viewshed mapping.

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looking for mature survivors and received reports of 1,500 trees scattered throughout the province, from Windsor to the Quebec border and as far north as Sault St. Marie. 0I Over a period of six years, Kock and Fox POOLS visited 600 of the mature elms and collect- 06 a freshwater alternative ed cuttings from approximately 300 hardy specimens. The cuttings have been graft- The growing consumer demand for non- ed on rootstock from a mature, healthy chlorinated swimming pools has spurred elm growing in Guelph. When the grafts the development of alternatives such as are between five and seven years old, saltwater and ozone pool systems. Now, they are injected with Dutch elm dis- natural swimming pools (NSPs)—a freshwa- ease—sometimes repeatedly—to see ter alternative—are surfacing across North how they respond. “It’s a miracle to see America. This trend follows on the heels of them survive after being injected three Europe and Great Britain where, since the years in a row,” enthuses Fox. He adds 1980s, thousands have been built. 0H that he doubts any elms are truly immune TREES to the disease, “rather, some trees just tol- Conventional pools rely on chlorine and 05 breeding elm's future erate it due to their unique genetic code.” other chemicals to maintain sterile, algae- free water, while NSPs are anything but Sometimes called a “dating service for Once the seedlings are screened for toler- sterile. They are living aquatic ecosystems, lonely elms,” sometimes known by the ance, the hardy specimens are candi- designed to look and function like a natural affectionate acronym ERP, the Elm dates for ERP’s breeding orchard at the pond, with lush living plant filters—the sig- Recovery Project at the University of University of Guelph Arboretum, where nature feature—surrounding an open swim Guelph Arboretum may have some playful proven disease-tolerant trees will eventu- zone. The plant filters, in turn, provide a names, but its purpose is deeply serious. ally be bred with each other. “The breed- habitat for birds, dragonflies, frogs, turtles, ing program will bring the best of the best newts, and a host of other fauna. Officially launched in 1998, the goal of the together, so their offspring will, we hope, Elm Recovery Project is to return the be able to tolerate whatever nature Science in a Nutshell beloved and iconic American elm to the throws at them.” Fox notes that it is this Natural swimming pools rely primarily on landscape. This stately, vase-shaped tree strategy of seed propagation, rather than complex natural microbial processes to was virtually wiped out by Dutch elm dis- cloning, that makes ERP unique: the Dutch purify and clarify the water. They incorporate ease. Although young elms still grace elm disease-tolerant cultivars available in rock filters and other bio-media where ben- streets, backyards, and farmer’s fields, the U.S., such as Jefferson and Princeton, eficial bacteria can colonize and perform most of them succumb to the disease for example, are clones, making them vul- the necessary cleansing action. These bac- when they reach fifteen to forty years of nerable should the disease mutate. “We’re teria are responsible for the aerobic decom- age. However, there are rare survivors, trying to make the odds as good as possi- position of organic matter accumulating in and it is these mature, relatively disease- ble,” says Fox of the breeding program, the system, thereby releasing nutrient com- tolerant giants that hold the promise of which is much more time-consuming than pounds sustaining zooplankton—a natural elm recovery. cloning. “Basically, we’re just doing what algae predator—and the plant filters. nature does—but we’re speeding it up by “These old trees seem to have the ability bringing isolated survivors together.” The plant filters are particularly effective at to compartmentalize the disease success- taking up nutrients, which further stymies fully, in effect to quarantine the disease in “It might take us fifty or sixty years to get algae growth. The bacteria are oxygen just a few branches, and keep growing,” a second generation of seeds from the dependent, which dictates the need for a says Sean Fox, horticulturist at the arbore- breeding orchard trees,” says Fox, clearly waterfall and submergent oxygenating tum. Fox is leading the project, following a very patient fellow. “I probably won’t be plants. Since the bacteria do not remove the death of ERP’s founder, Henry Kock, in around...” But he’s not only patient, he’s potentially harmful pathogens such as e- 2005. “Henry had this idea,” says Fox. “He cheerful: “Can you imagine what an coli, UV filters are generally recommended wondered why some elms were still amazing sight those elms will be?!” as a non-chemical water treatment. alive.” Kock put out the word that he was TEXT BY LORRAINE JOHNSON, EDITOR OF GROUND. TO SUPPORT THE ELM RECOVERY PROJECT WITH A TAX-DEDUCTIBLE DONATION, VISIT WWW.UOGUELPH.CA/ARBORETUM/.

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Design and Construction Keeping it Clean 0J NSPs are typically designed to look like a Natural swimming pools are not mainte- natural pond, with curved organic lines, nat- nance-free and bacteria must be added on ural stone edges, and substantial plantings an annual basis. The pool bottom should be RE-USE 07 urban tree salvage both in the “filter” area (which is separate vacuumed every week or two to prevent from the swimming area) and around the sediment build-up. Skimmers should be Although landscape architects often strive perimeter to reinforce the naturalistic cleaned every couple of days and leaf nets to save the existing trees on a project site, appearance. They can also be designed to may be required in the fall if trees surround it is not always feasible. Many of these resemble a conventional pool, with the plant the pool. Plant filters may require thinning removed trees become mulch or fire- filters and biofilter located in an area away every few years. On the plus side, NSPs do wood, a fact that Urban Tree Salvage, a from the pool. They can be constructed to not have to be drained for the winter. unique Scarborough company, is trying to any size, though a swim zone roughly the change. According to their website, size of a typical residential pool will require It is possible to heat a natural swimming approximately nine thousand trees are 30-50 percent more space to account for pool, but only if you are prepared to monitor removed from the Greater Toronto Area the plant filters. water temperature judiciously. A heater can each year due to storm damage, age, help extend the swimming season in the insect and disease problems, and con- Like any pool, the construction of an NSP spring and fall, by holding temperatures at struction projects. That’s a lot of trees! begins with a hole in the ground. The simi- no more than 70 degrees Fahrenheit. In larities end there. The basin is excavated fact, by heating in the early spring, bacteria In operation since 2005, Urban Tree with sloped walls to a depth of 7-8 feet, with that would otherwise stay dormant until the Salvage (UTS) has re-routed thousands of a 3-foot-wide shelf halfway down. The shelf water temperature reaches 65 degrees trees from chippers and landfill into cre- serves as a base for a 3- to 4-foot high Fahrenheit can be activated to avoid cold ative furniture and accessories. The com- retaining wall constructed of rot-resistant water algae blooms that tend to occur just pany also offers a wide range of lumber, wood, which separates the plant filters from after the ice has melted. However, come some with very unusual grains and inter- the swim zone. The basin is lined with a the summer months, the water temperature esting origins. They make candle holders, black, “fish-friendly” rubber liner. Perforated will rise well above the 70-degree- for instance, from old-growth pine which pipes are placed behind the retaining wall, Fahrenheit threshold, and adding more was salvaged from Toronto’s historic and covered with layers of graded granite heat would be reckless; algae thrive in Queen’s Wharf (circa 1830). river rock—a highly effective bio-media warm water and aquatic plants hate it. readily colonized by beneficial bacteria. There is also the option of ordering items The rock filters are capped with pea stone, For the most part, NSPs typically cost from the very trees that you remove from which is used as a substrate for a wide about the same as a conventional pool your site. Whether the final product is range of native emergent and submergent of a similar size, though features such as made by UTS, or you produce it elsewhere aquatic plantings. The perforated pipes are elaborate waterfalls can, not surprisingly, from the lumber milled by UTS, having connected to one of two circulation systems. escalate costs. those removed trees reappear as bench- Water pumped through the plant and rock es, bollards, or fence components would filters is discharged back to the bottom of Natural swimming pools are not for every- be a unique site feature. the pond via a return pipe. one. If the idea of swimming in a pond or lake is a turn off, or if the thought of swim- Visit the company’s website at The second circulation system pulls water ming next to plants is unnerving, or if you www.urbantreesalvage.com for more through one or two skimmers located along want a heated pool, other swimming pool details on UTS’s lumber and built products. the shoreline to filter out larger floating parti- options should be considered. Yet for the TEXT BY HELEN POWERS, OALA, A FORMER MEMBER cles, dead insects, and leaves. Water drawn right homeowner on the right property, nat- OF THE GROUND EDITORIAL BOARD. through the skimmers passes through the ural swimming pools can be a beautiful,

UV filter before emptying into a biofilter— refreshing, ecologically sensible alternative 0H/ Henry Kock, ERP’s founder, essentially a plastic box filled with bacteria- to a conventional pool. with a mature elm IMAGE/ Sean Fox TEXT BY JEAN-MARC DAIGLE, OALA, PRESIDENT OF GENUS laden bio-media—before cascading over 0I/ Natural swimming pools are LOCI ECOLOGICAL LANDSCAPES INC., A SCHOMBERG-BASED living aquatic ecosystems that the top of the waterfall. DESIGN/BUILD FIRM THAT CONSTRUCTS NATURAL function like natural ponds. SWIMMING POOLS. IMAGE/ Genus Loci Ecological Landscapes Inc. 0J/ Old-growth pine bench made from recycled wood

IMAGE/ Urban Tree Salvage

Tree Myths and .05 10 Tree Debates Tree

Myths Myth: When planting a tree, it is fine to leave the burlap tied around the root ball because it will rot away. and In response to this common misconception, certified arborist Todd Irvine of Bruce Tree Expert Company of Toronto offers an emphatic “Arghh!!” While he agrees that the burlap will rot, he adds “yes, in years. Why would you not do everything in your power to give the Tree tree a fighting chance?!” The problem with leaving the burlap on is that small fibrous roots can not push through it. As well, notes Irvine, “burlap acts as a moisture wick, pulling water away from the roots just when they need it the most, post-planting.” Irvine suggests that an even greater problem is the tie used to hold the Debates burlap in place: “If left on, it can girdle and kill the tree in a Experts dish the dirt on matter of years.” common misconceptions Instead, Irvine says that all ropes and ties should be removed, the wires of the basket bent back and cut off, and as much of the about trees, and dive burlap removed as possible: “As an arborist, I would never leave that stuff on.” into debates about Myth: controversial practices Trees are the lungs of the planet.

It may work as a metaphor, capturing the public’s attention and TEXT BY JOCELYN HIRTES, ASSOCIATE MEMBER, reinforcing the notion that trees are a good thing, but as science, OALA, AND LORRAINE JOHNSON it’s a somewhat slippery analogy.

Consider what lungs do: in respiration, we breathe in oxygen and breathe out carbon dioxide. Yet when people use the “lung” metaphor for trees, what they’re usually referring to is the idea that trees take in carbon dioxide from the air and release oxygen—in other words, the exact reverse of what human lungs do.

It gets even more complicated, though, because the oxygen-pro- ducing capability of trees is just one side of the equation. Trees take in carbon dioxide and release oxygen when they’re photo- synthesizing during the day, but at night, the reverse occurs and trees take in oxygen and release carbon dioxide.

However, this is not to say that trees contribute to the build-up of carbon dioxide in the atmosphere. On a global scale, the amount 01 of carbon dioxide absorbed by plant matter is double the amount of carbon dioxide plants release through respiration.

01/ Planted in 1701, this eastern hemlock lived for 295 years. So, yes, trees produce oxygen, but the “lung” metaphor is IMAGE/ Henry Kortekaas 02/ Tree ties and stakes can cause damage to trees. a bit misleading.

IMAGE/ LEAF (Local Enhancement and Appreciation of Forests) 03/ Trees slated for removal can sometimes be retained, depending on location and other factors.

IMAGE/ Lorraine Johnson

Tree Myths and .05 11 Tree Debates

However, Ian Bruce, founder and senior consultant with Bruce Tree Expert Company of Toronto, says, “I always encourage clients to provide some form of supplemental support when planting large trees. This is especially important on open windy sites, and/or in cases where the tree has a large, well-developed 02 crown and a limited sized root ball. The number one reason is to Debate: anchor the tree long enough for the fragile, fine roots to grow out Due to the effects of climate change, we should be into the soil, to replace those lost when the tree was moved.” planting southern species now. Bruce stresses, though, that once the stakes have served this function—usually after one or two years—they should be John Ambrose, a conservation biologist based in Guelph, takes a removed. He also cautions against staking trees so tightly that broader view: “The biggest challenge for trees in southern Ontario they can’t bend at all in the wind: “Trees are perpetually self-engi- is the disconnectedness and fragmentation of the forest matrix.” neering. They expend energy where they need to. So if they’re Quite simply, tree populations are isolated from each other, exist- allowed to bend a bit—say, if there’s an inch of play between the ing in pockets separated by urban development and agriculture. tie and the trunk—this strengthens the trunk. Biomechanically, the “What we should be doing is looking for ways to reconnect that tree responds to the need to support itself by developing a strong fragmented network, to restore the matrix, so that seeds of the trunk in response to the movement. Allowance for natural trunk best adapted trees within natural forest populations can move movement will result in increased diameter development and on their own across the landscape in response to climate change. a more noticeably uniform taper from the ground up to the first In addition, increasing the percentage of forest cover helps mod- main branches. “ erate climatic extremes.”

Debate: To stake or not to stake?

According to Richard Ubbens, City Forester, Toronto, “Staking is absolutely not necessary; it’s a big mistake we have all been making for decades.” Ubbens notes that “where you have stakes, you see lots of issues caused by girdling. And you are not seeing the root flare and you are not seeing the stem diameter growth because stakes are restricting the natural hormonal response to wind. The wind moving the stem causes a specific hormone to stimulate stem growth and anchor root development and root flare—a key component of getting trees established.”

In response to the idea that on windy sites where the soil is new and uncompacted, trees need to be stabilized by staking, Ubbens says: “As long as you make the tree pit wide enough when you dig the hole, staking is not necessary; just firm in the soil at the bottom side of the root ball. Then all the material that goes in beside the root ball does not need to be so compacted. We always emphasize the importance of fracturing the parent soil. 03 If you do this properly, you will have roots growing into the undis- Myth: turbed soil within a month. There is no issue with stability.” All dead trees should be cut down.

With regards to bare root trees, Ubbens says: “We sometimes use For many people, the idea of leaving a dead tree standing verges a two by two wood stake with a biodegradable nylon tie that on heresy. It goes against conventional concepts of aesthetics and breaks down in UV light and will be gone within a year. Even then, safety, for a start. But Philip van Wassenaer, founder and owner of it’s only if a bare root tree comes with few roots. Nine out of ten Urban Forest Innovations Inc. based in Mississauga, argues that bare root trees don’t even need staking.” dead tree management conventions need to be challenged: “We

Tree Myths and .05 12 Tree Debates

need to turn North American perceptions around.” If that’s too Acknowledging that shade will limit the effectiveness of solar much of a stretch, he offers a qualification: “I’m not saying that panels, Pickering sees a crucial role for landscape architects at we should leave big old nasty dead silver maples hanging over the design stage: “Landscape architects need to think about how Yonge Street, just that there are lots of appropriate places— landscapes can be designed in a way that integrates the benefits ravines and extensive back yards, for example—where we can of trees and potential solar installation.” The solution is not fewer safely leave dead trees.” trees, says Pickering, but strategic placement of trees through the design lens of solar opportunities. Wassenaer urges consideration of the ecological importance of standing dead trees (also known as snags) and trees with dead Myth: parts or “defects.” “They provide unique habitat for organisms that Mulch should be mounded up around the base of trees. depend on them and that will not exist without them. Old and dead trees act as a sort of ‘ark of biodiversity’ that allows certain Incorrect mulching practices abound—examples can be found species to persist over time.” He points to research being done in everywhere—but a particular insult to trees is the practice known Great Britain by Keith Alexander and the work of Neville Fay of the as “volcano mulching.” “This is when people pile new mulch Ancient Tree Forum. In Britain, close to 1,800 species (approxi- around the base of trees and up the trunk, so the tree looks like mately 6 percent of the total known fauna of Britain) are depend- it’s erupting from the mulch,” explains certified arborist Todd Irvine ent on the process of wood decay in trees and shrubs. of Bruce Tree Expert Company of Toronto. “It’s based on a complete misunderstanding of trees and root growth.” To the question of safety, van Wassenaer responds: “A tree is not a hazard if there is no target.” Thus, location is key—close One of the problems with volcano mulching is that it threatens proximity to buildings and public routes is out, for example. the health of a tree’s bark: “The mulch traps moisture against Likewise, certain tree species are more appropriate for retention the bark—it can rot the bark right off the tree,” says Irvine. than others. “Oaks, sugar maples, and white pines, for example, Another problem is that it inhibits gas exchange in the bark will, in general, stand stable for a long time even when dead,” and the root ball. he says, “as long as they didn’t die because of significant decay or root problems.” Instead, Irvine recommends that a 5- to 10-centimetre layer of composted wood mulch be applied evenly for at least a 1- Wassenaer suggests that for appropriate dead trees in appropri- metre radius from the trunk of young trees and out to the drip ate locations, branches could be removed, leaving a sturdy trunk. line of larger established trees. The layer of mulch should taper “Without the branches, there won’t be any lateral forces acting on down to meet the original soil a couple of centimetres before the tree—only gravity—and inertia will keep it standing.” reaching the trunk.

As for how people react to the idea, he acknowledges that while he advocates for leaving dead trees standing in certain situations, “this is not yet considered normal behaviour.”

Myth: Trees inevitably interfere with solar panels.

Mary Pickering, Acting Executive Director of the Toronto Atmospheric Fund, is concerned that two environmental strategies to combat climate change—planting/preserving trees and increased use of solar panels—are sometimes pitted against each other. “We certainly don’t want solar panels to be another excuse for people to say that ‘trees are in the way.’ When we hear requests to cut down trees to put up solar panels, we just shriek! That’s because a mature tree shading a house might be providing greater net emissions reduction benefit—through reduced need for air condi- tioning—than solar panels could.”

Tree Myths and .05 13 Tree Debates

05 Myth: Myth: The majority of tree roots go down deep. Trees cannot be planted in decommissioned, capped landfills because their roots will puncture the cap. We should all be sent back to school to re-draft those drawings of trees we did as children—those lollipops sticking out of the When Dr. Steven Handel, Director of the Center for Urban ground, with not a root in sight. (If we did draw the roots, it was Restoration Ecology and a professor of plant ecology at Rutgers, probably just one spindly anchor going down deep in the ground.) was asked by the New York City Sanitation Department to restore a decommissioned landfill, he proposed planting the site with “The whole idea that all roots go down deep is completely false,” native trees. The response from the civil engineers was immediate says Todd Irvine. “The majority of a tree’s roots are in the top foot and emphatic: trees could not be used because their roots would or two of soil.” Instead of growing vertically, extending down, most puncture the protective clay or geomembrane cap, allowing water roots form a huge horizontal network that extends outwards, well to percolate down through the garbage and contaminate the beyond the drip line. “Roots form a mat just below the soil’s sur- groundwater. “These engineers were highly educated but they face,” says Irvine, noting that in ideal situations an open-grown were not trained in biology,” says Handel. “They weren’t convinced tree could have a root zone that extends two or three times the that the roots would stay in the soil above the cap.” radius of the drip line. And so Handel embarked on a three-year experiment. He plant- Thus, any excavation done in that top foot or two of soil must be ed one hundred trees and shrubs on a capped landfill and one done carefully, to avoid damaging the extensive network of roots. hundred on an adjacent site as a control. When he dug up the roots a few years later, he found that the roots of the control trees went down relatively deep, but the roots on the landfill site hit the 04/ Volcano mulching is bad for trees. cap and then went horizontal, staying on top of the cap. IMAGE/ Lorraine Johnson 05/ A cluster of installed trees and shrubs at Fresh Kills landfill, eight years after installation “The truth is that roots are smart,” says Handel. “They move to the

IMAGE/ Steven Handel zone of least resistance where there’s moisture, oxygen, and their needs are met.”

The legacy of Handel’s research is that, in the US, trees are now regularly planted as part of the restorations of decommissioned landfills. And word is spreading to Canada. When Handel attend- ed a conference in Guelph last year, where a plan for turning a decommissioned landfill into a pollination park was discussed, he made a compelling case that trees have a role to play: “It’s possible to have native trees all over these old landfill sites. They will not interfere with engineering goals; in fact, they complement the goal of lessening leachate by transpiring water.”

BIO/ JOCELYN HIRTES, ASSOCIATE MEMBER, OALA, IS A CERTIFIED ARBORIST AND A MEMBER OF THE GROUND EDITORIAL BOARD.

BIO/ LORRAINE JOHNSON IS THE AUTHOR OF THE NEW ONTARIO NATURALIZED GARDEN.

Genes Matter .05 14

TEXT BY BARB BOYSEN

Trees are alive—seems obvious. But then why are they often treated like fences or lamp posts? Trees have needs that are largely under genetic control. What this means is, pay attention or suffer the conse- Genes quences: diseased, strangled, abused, not-meeting-their-potential, dying-before-their-time, waste-of-money trees.

Genetically controlled needs of trees vary by species, by source of Matter seed, and by individual responses to climate, soils, drainage, and light. As well, trees have evolved as part of a system of give-and- take with insects, diseases, other animals, and plants. So, if both Sourcing the tree’s individual and system needs are met, it will thrive, giving us amazing benefits over decades, even centuries, and appropriate even in cities. trees to ensure Not recognizing this genetic complexity, or proceeding in spite of it, has costly consequences, which accumulate in tending or in replanting success poorly planted trees. There is also a cost in terms of not meeting objectives such as beauty, shade, windbreak, etc. Perhaps we don’t articulate what we expect from trees or consider how best to achieve our goals. Maybe it’s too much about growing and planting and not enough about what and where we’re growing and planting.

For too long, people have brought in plant material from distant and different places, often ignoring the local forest wealth and the value of its local adaptedness. At first, maybe this didn’t do a lot of harm. But who foresaw the erosion of the natural forests in and out of cities? Who knew we’d face the chestnut blight, Dutch elm disease, and now Asian long horned beetle and emerald ash borer? Who knew Norway maples were so susceptible to tar spot, would threaten our ravines with erosion, and then not even thrive for more than sixty years? Who knew we’d remove the topsoil and compact the rest?

We need to get back to the basics—to understand basic tree functions over long time periods. We need to understand how to marry the climate and site to the tree and to our objectives, and then make aesthetic choices. And we need to ensure diversity with enough variation to make sure the system as a whole keeps functioning, because the stakes are getting higher and the pressures greater due to the scary and costly effects of invasive insects, diseases, and climate change.

01/ Many of Ontario’s tree species are genetically adapted to the If there was ever a time to start doing things right, it’s now. So why climate conditions of their local area. are we still planting too few species, mostly exotics, of unknown IMAGE/ Forest Gene Conservation genetic provenance, or too many clones, in places where no one Association should expect any tree to thrive? Is it client ignorance, or lack of planning, or short-term economics, or all of the above and more? What are the barriers to doing the “right thing,” and how can we work together to remove these barriers?

Genes Matter .05 15

Unfortunately, genetics, the seed source or provenance of a tree, is a largely ignored part of tree planting. Many species are native throughout large areas, and therefore throughout many different climates. In southern Ontario alone, our growing season can vary from 239 days in Windsor to 215 days in Ottawa to 185 days in Algonquin Park. Summer and winter temperatures and precipita- tion can also vary greatly.

Scientists have discovered that many species have evolved to become genetically adapted to the climate conditions of their local area. This means, for example, that a red oak which evolved over many generations in the highlands of Algonquin Park is genetically different in its adaptation to climate from a red oak that evolved in Toronto. When a red oak is moved to a different set of conditions, even within its “native” range, it may suffer from spring or fall frosts, moisture or heat stress, and snow or cold damage. These stresses can kill the tree or result in reduced growth, or reduced vigour, which then makes the tree more susceptible to insect or disease damage. However, we don’t know the degree to which seed source matters for most species, and cutbacks in environmental research mean that we likely won’t gain this knowledge any time soon. But we do know that consid- erable geographic and genetic variation exists for many of Ontario’s tree and shrub species.

So knowing that for some species variation does matter, we can act to limit both the ecological and economic risks by matching the 01 conditions of the source of the seed to the conditions of the planting site. The Province of Ontario has used this principle to implement a policy of tree seed zones that forest companies must respect when collecting seed and planting trees on Crown land.

While mandated by the Province for the forestry industry, seed source is largely ignored in the landscape industry. And it is in this sources similar to our climate and identified as such, maybe our realm that landscape architects have an important role to play. tree planting efforts will be more successful and more economical. The Forest Gene Conservation Association has a program to help practitioners (consumers and professionals alike) get the most If the tree you specify and plant does not have the genetic appropriate trees for their needs. It is a voluntary seed and stock potential to survive and thrive in the conditions of your planting certification program. Members of the private sector—from seed site, no amount of tending, fertilizing, irrigation, or pest control will collectors to seed processors to growers—can participate by reg- help it grow as vigorously as a tree sourced from appropriate istering the source of their plant material and subjecting them- genetic stock. A tree’s chances for success lie first in its genes. selves to inspections and audits. This stock will then be eligible to Ask about seed source. be marketed as “Ontario’s Natural Selections.” Here’s hoping that all the trees you plant this year will live for one Landscape architects can help by asking for certified stock and hundred years or more! requiring planting specifications to include source-identified trees BIO/ BARB BOYSEN IS COORDINATOR OF THE FOREST GENE CONSERVATION ASSOCIATION, A NON-PROFIT GROUP WORKING IN SOUTHERN ONTARIO TO PROMOTE THE CONSERVATION that are adapted to local site conditions. This demand will help to AND RESTORATION OF URBAN AND NATURAL FORESTS. FOR MORE INFORMATION, create a better supply. If we can ever get to the happy circum- SEE WWW.FGCA.NET. stance where native trees for urban landscaping are grown from

Trees for .05 16 Life Trees for Life

Richard Ubbens, City Forester for Toronto, speaks with Nancy Chater, Associate Member, OALA, about trees and how landscape architects can contribute to the health of the urban forest

Trees for .05 17 Life

Nancy Chater (NC): What can landscape NC: Subsoils are very different. NC: I’m familiar with compost tea at the architects do to improve the lives of scale of the garden. Is it being used at an urban trees? RU: Exactly. We mess with soil chemistry, urban scale? texture, and soil’s biological systems so Richard Ubbens (RU): Soil science is that it becomes anaerobic, essentially a RU: We have a couple of 1,000-gallon something that not only landscape archi- dead organism. Then we truck it back and tanks at one of our yards, and our trucks tects but the urban forestry community as call it “soil.” By that time it could be better will fill up with water and top up with a whole could improve upon. Landscape called “dirt.” Soil is the biggest factor in compost tea and water our trees. It’s architects are better than most urban why we are getting short-lived trees, very effective. foresters at thinking spatially and envision- unhealthy trees, and stunted trees in ing what the landscape is going to our cities. TREE ROOTS AND INFRASTRUCTURE become, but there is a lack of soil science. The challenge is: how can we provide, in NC: What do you think about industrial- RU: We also have to look at what is in the an urban built form, a better environment scale manufacturing of soils, including soil in terms of being full of utilities and so that trees are healthy and live as long triple mix and compost? infrastructure. as they should? RU: Triple mix is too rich, too high in NC: The competition for space below With the intensification of city building, organic compounds, to be used for any- grade in urban contexts. there is good work going on in planning to thing other than to get plants started. Two make cities work better in a more dense thirds of it will break down quickly; you will RU: That’s right. So understanding tree form. But, still, the very first thing and last be left with only one third of your soil. At roots and their relationship to utilities is thing that is impacted is the soil. When the the City, we specify sand/silt/clay mixtures another emerging area. People ask: “if we first truck backs up to remove the trees on with a little bit of biomass to try to create have tree roots going in and around and a site, the soil starts to be compacted and something like a natural soil. More like a through utilities, is that okay?” We know it’s disturbed. Then we have these practices clay loam or sandy loam, because that’s okay as long as we design it well in terms of removing the soil, stockpiling it, building, what we have around here. Toronto has a of giving enough space so that eventually and bringing soil back. When we are lot of sand. That is very different soil, but it someone can access the utilities without done, the soils are often unrecognizable. is natural. So we specify high sand content compromising tree roots. Hopefully, gone When we say “let’s restore the soil,” very along our roads. It remains moist but it are the days where we say, “We can’t few people know what we are talking moves water easily; it moves nutrients plant trees here because we have a utility about. And without good soil we are not easily. It doesn’t compact from vibration conflict.” I hope that landscape architects growing good trees. of traffic. now understand where and how roots grow and why they don’t destroy utilities. NC: So the ways in which landscape We also have lots of clay soils naturally in Roots are not aggressive, they are not out architects specify soil and address meth- our region. You would never spec a clay there damaging infrastructure. They are ods of handling soil on a site have to be soil because you can’t put it back on a site just opportunistic and going where soil reviewed and become better informed without compacting the heck out of it. So conditions are good. by soil science? you’ve got to go to a clay loam. I prefer to use parent soil material that is still alive, NC: Does that require a re-education of RU: Yes. And there is no “one solution fits whenever possible. Ideally, we would put people on the utilities side as well? all” answer. For example, in Toronto we back the C, B, and A horizons. But that is a started addressing street trees at one lot of work and expense, so we don’t do it. RU: Absolutely. Landscape architects can point and the need to improve their grow- help the engineers out there, especially on ing conditions. We talked about soil vol- The upper horizon needs to be a living the utilities side, to understand how utilities ume, quality, structure, and drainage pat- horizon. That’s where compost comes in. can be located so trees are not going to be terns. The next thing you know, our work The compost being manufactured is alive, constantly affected, and similarly so the on street trees was taken as the solution. it’s full of microbes, but it doesn’t contain trees can be maintained and have enough Yet we know that different species grow in the natural soil microbes found in the for- soil volume without breaks in the soil different soils; we have slopes and valleys est. If there was more leaf mold, it would with differing drainage patterns, sun have more natural microbes. Compost is 01/ Roncesvalles Avenue in Toronto has a aspects, and so on. highly variable. You need to carefully modular system of raised planters with open bottoms, trench planting, and specify what you are after with compost. bridging sidewalk pieces in between planters that are structurally supported It’s a good product because it stimulates by concrete frames, allowing the soil microbial action in otherwise dead soil. volume to remain uncompacted. Compost tea does that, too, and is IMAGE/ City of Toronto highly valuable.

Trees for .05 18 Life

caused by all kinds of extensive excavation. early, and begin to prepare the soil for the If we put the utilities deep enough, we can next generation of trees. We want to do a grow roots over them, no problem. We lot better than that. For instance, on some of need to put utilities lower, and group them our planting projects we are now spending together. If we look at the science of tree more than half of the budget on soil prepa- roots, they need oxygen, water, nutrients— ration. The costs are high but the results are those are all at the surface. that the roots will spread out from confined soil into surrounding areas that have been We can look at San Diego as a precedent prepared properly. for change. They decided to place all utilities under the road, not in the planted We have examples now of tree planting boulevard. They recognized they were methods for densely built areas that are doing too much damage to trees when more modular and allow for greater soil replacing or upgrading infrastructure. They volume and uncompacted soil, using recognized that trees have tremendous approaches such as bridging sidewalks, value; while roads are being replaced soil cells, and structural soil, combined every twenty to thirty years, trees are last- with trench planting rather than individual ing sixty to eighty or one hundred years. tree pits.

We need to step back and ask: can we PRIVATE PROPERTY AND THE not relocate utilities to allow more growing HUNDRED-YEAR TREE space for trees? If we deal with trees and infrastructure on a project basis while RU: Beyond the engineered street, we keeping the big picture in mind, recogniz- know that there is far more private than ing what twenty years of this kind of work public property in Toronto, and there are will achieve, we can come up with much many more trees on private property. The better standards. work of landscape architects on private property, therefore, is especially important. MISCONCEPTIONS We know that the homeowner lives in one NC: What are the major misconceptions place for eight years on average and that about the way tree roots grow? tastes change over time, creating a tremendous impact on the urban canopy. RU: A lot of people think of roots going Look at the way we are using stone and down, but what we have to think about as pavers now in comparison to fifteen or going down is water—the movement of twenty years ago when there was almost water up and down, and nutrients moving none and there was a lot more grass. up and down. Tree roots grow out, mainly in Outdoor entertainment space is in the top 60 centimetres of soil with some demand now and is being used more roots going deeper, but 90 percent of the intensely, with bigger decks and patios. time the bulk of the biomass is in the upper In the face of these changes, we need to 60 centimetres. have people thinking about the hundred- year trees, not the twenty-year trees. So while roots are important, we have to There needs to be something in every think as much about drainage and porosity landscape plan for the hundred-year in the soil. If we have a compacted sub- trees. If you look at older parts of Toronto, grade and load in nice soil, with an abrupt you find large trees around the property transition, we don’t get normal moisture flow line. Around the perimeter, trees may last or proper drainage because we don’t have longer, so that may be a good place to natural movement between the soil layers. locate new trees on private property. As a result, on dry days you don’t have water migrating up, as it would naturally, and you don’t have proper drainage. You may have a hardpan. The first generation of trees in this condition will grow roots and die

Trees for .05 19 Life

We are also promoting natural garden RU: We are beyond the beginning. It’s RU: Huge. For example, people always management in Toronto. For landscape not yet a wide-sweeping paradigm shift, talk about the way trees can absorb car- architects working on ravine properties, but we are on the cusp of it. I think the bon dioxide from cars. And they will, but it is important to use plant materials that younger generation—those coming out of what they absorb compared to the total create natural ecosystems and regenera- university within the past five years, and output of all cars in a city is a depressingly tion so the ravines are healthy. It’s a big those in school—understand that environ- small number. We’re doing a canopy opportunity because Toronto has 30,000 mental challenges are huge. They have study with the US Forest Services that will properties on our ravines. been taught the value of trees, the impor- soon give us clear numbers. The studies tance of water, the need to moderate cli- are showing that trees can absorb virtually GENETIC DIVERSITY mate. Whether they have a full under- all of the nitrous oxide and sulfur dioxides standing of trees is another question. that cars emit, and that’s substantial. And RU: Genetic diversity is another key area. Trees are highly complex. Yes, we can trees are offsetting fossil fuel consumption We’re all used to dealing with clones. all grow trees and shrubs, but can we and providing carbon offsets because they What we should be dealing with is seed- grow them well? are shading homes. If that number can be grown material because we need the quantified, then you start talking multi-mil- cross-pollination with different genetic On the economic side, we are starting to lions of dollars of value for the urban for- stock, as happens in nature, instead of this get projects with figures in the hundreds est, depending on the size of the city. If we massive cloning. There is tremendous nat- of thousands of dollars for trees to be look at the value in terms of particulate ural variety among species that we need removed and replanted. Sometimes matter that is taken out of the air by trees to embrace. developers are really surprised at the total and the effect of that on health care, that value of the securities they have to put for- is huge; if we look at trees in terms of skin We also need to recognize that the urban ward to municipalities. While the cost com- cancer prevention, it’s huge. environment is a dangerous place for pared to the total project is still small in trees in terms of their susceptibility to percentage, it is a lot of money. Another We can look at real estate value and the insects and diseases that can affect a San Diego example involved a hydro line question of what do trees mean to the whole species or even a whole genus, project that changed its course of action importance of where I live. I always say especially when the plant stock is geneti- due to the cost of trees that would have to that without the trees it’s a subdivision, cally the same. There are various projects be removed and replaced. The project and with the trees it’s a community. and small growers that are actively pro- budget in total was about $20 million and BIO/ NANCY CHATER, ASSOCIATE MEMBER, OALA, IS THE TECHNICAL CORNER COLUMNIST FOR GROUND AND ducing genetic diversity in plant material the trees were just five percent of that, but A MEMBER OF THE EDITORIAL BOARD. and making it available—a great resource that was still well over half a million dol- BIO/ RICHARD UBBENS IS THE CITY FORESTER FOR TORONTO, RESPONSIBLE FOR THE OVERALL COORDINATION OF THE for landscape architects. lars. As a result, they decided to put the URBAN FORESTRY PROGRAM, INCLUDING FORESTRY POLICY, PLANNING, PROGRAMMING, PRACTICES, SYSTEMS lines under the road. That was the mone- DEVELOPMENT, FOREST MANAGEMENT IN RAVINES AND NATURAL AREAS, AND INTEGRATED FOREST HEALTH CARE. RE-VALUING URBAN TREES tary value only. If they carried it one step further and went to the community and NC: The approaches you have talked said, “We are planning to remove all these about—such as rethinking the relationship trees,” they would have witnessed a differ- between utilities and tree roots, establish- ent value expressed, one that is more ing new construction methods that support about the intrinsic value people put on tree growth—require a re-valuing of trees trees. It’s something they can’t describe, on many levels. Do you see a paradigm they just know they like them and they are shift? Are we at the beginning, or further in? not prepared to see them go. People get very vocal. So yes, that piece about valuing trees is there.

NC: And then there’s what I would call the environmental infrastructure value—such as the canopy and all that it is doing in terms of cooling and air quality, moderat- ing the urban heat island effect, and so on. That aspect is huge.

Should it Stay or .05 20 Should it Go?

Should it TEXT BY LORRAINE JOHNSON Philip van Wassenaer’s glasses magnify the already intense look in his eyes, and when he talks, you get the feeling that nothing animates him more than an enthusiastic discussion about trees. The founder and owner of Urban Forest Innovations Inc., based in Stay or Mississauga, van Wassenaer’s commitment to all things arboreal verges on obsession. (Get him going on the subject of heritage trees and pretty soon you’re experiencing the vicarious thrill of being high up—say, 300 feet—in the canopy of a 1,900-year-old Should it Californian redwood giant...) But what really gets him going is the subject of the urban forest— specifically, the need to protect old trees that others are inclined to write off. Go? “The average arborist has a propensity to panic about old trees,” he says bluntly of his profession. As do municipalities and home- owners. It’s understandable, of course, because with every major The risky business of windstorm, there’s bad news: trees or branches down and the associated liability that goes with this. tree assessment Until relatively recently, assessing tree hazards has been an inexact science—drilling, tapping, looking for signs of decay. “But these methods don’t tell you how much decay there is and where,” says van Wassenaer. “There’s no quantification.” Thus, he’s championing something called the Elasto-Inclino Method (or, colloquially, the “pull test”), which was developed in Germany in the late 1980s and early 90s to scientifically test the safety and stability of trees. Wassenaer is the only arborist trained and equipped to conduct pull tests in North America and he has used this tech- nique on approximately 150 trees in the past four years.

“It’s very similar to what structural engineers do when they apply structural engineering principles to safety analyses of buildings, bridges, and other structures,” he explains. Basically, the three key components of structural analysis include the properties of the material (in the case of trees, the compressive strength of green wood fibres), the force acting on the structure (for example, the wind), and the geometry of the load-bearing parts of the structure (the weight of the tree and the hollowness or soundness of the stem distribution of branches).

To conduct a pull test, one end of a steel cable is attached to a sling installed in the crown of a tree, and the other end is attached to a winch. The winch is used to simulate wind force acting on the tree’s crown; as force is gradually applied, a load cell measures the force in the cable. As the trunk bends, changes to the tree’s wood fibres are measured with an elastometer. Yet another device, an inclinometer, measures the reactions of the tree’s roots to the force. All of the data is analyzed by a computer program that extrapolates how a tree would react under gale-force winds and provides the safety margins for that particular tree.

02 “These sophisticated tests allow us to make good decisions about the hazard level posed by a suspect tree,” says van Wassenaer. It’s particularly useful, he notes, for trees that have had their roots severed during construction. “More than 50 percent of the time, we’ve tested trees slated for removal and been able to retain them. Sometimes, they require pruning, and the computer program allows us to show how pruning will increase the balance and safety of the tree.”

As for price, although it varies according to the specifics of the site and the tree, van Wassenaer suggests that anywhere between $1,200 and $2,000 is typical. Along with doing the test and running the data through the computer program, he provides a full report.

“We’ve had situations where the municipality says a tree has to be removed and the neighbours are in an uproar. On the other hand, we’ve had a homeowner say a tree is unsafe and the municipality wants to keep it. What we offer is unbiased and independent expertise to determine the safety of the tree.” While he is quick to stress that “as experts on risk assessment, we do not counsel people to keep dangerous trees,” it’s clear that for every tree saved by a pull test, van Wassenaer is thankful.

BIO/ LORRAINE JOHNSON, EDITOR OF GROUND, IS A BOARD MEMBER OF LEAF (LOCAL ENHANCEMENT AND APPRECIATION OF FORESTS).

01/ Tree stability testing

IMAGE/ Philip van Wassenaer 02/ Assessing decay at 95 m above the forest floor in the canopy of a giant sequoia, Eureka, California

IMAGE/ Philip van Wassenaer

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Victoria Lister Carley (VLC): All of our prac- care of by an arborist, the tree will suffer far tices are affected by the regulations relat- less from whatever you’re going to build. ed to trees. Now that we’ve had a number Knowing that you’re going to have to get a The of years living with these regulations (such permit to damage the tree gives people an as tree protection zones, permits for opportunity to think about the future a little removal, etc.), how is it going? Is there bit. Start with an arborist or an arboriculture meaningful improvement? Is there any- company, before you even get the permit, Urban thing we should be doing to guide politi- because with proper long-term care trees cians to make better regulations? can be healthier.

Paul Marsala (PM): We’re working on a VLC: Going back to the issue of it being Forest development where there were about ten cheaper to just pay the fine relative to the trees, probably in the range of 12-inch cal- time it takes to get a permit, do you think liper, which could not be preserved people would respond more positively if the As more and more munici- because of the grading situation. But the system was faster? palities implement tree pro- “three for one” legislation means we’re tection bylaws, how is the actually going to have more trees. The PT: Certainly, that’s one of the complaints, developer was in favour and had no prob- that if they go for a permit to remove a tree, urban forest faring and lem in allowing more trees to be planted. it may take up to three months. If you were what can those who are Typically, developers say “I don’t want trees to say we can get a decision in two weeks, involved with specifying on my property,” but that’s changing. they might go through the process but and planting trees— nothing says you’re going to get a permit at VLC: I worry a bit about people getting the end of the process. If the permit is arborists, landscape archi- rid of trees when they know trees are denied, now you’re stuck with this tree that tects, and developers—do supposed to be protected. Are the everybody knows about, they know the to ensure that the urban fines enough? size, they know the condition, you’ve just forest flourishes? admitted you have this tree, but you still Patricia Thomson (PT): Trees go missing need to get rid of it. all the time. Trees get removed without per- Moderated by mits. I think the majority of people want to Jeffery Silcox-Childs (JS-C): It’s easier VICTORIA LISTER CARLEY, OALA do things properly and they follow the rules, to plead ignorance than to ask but others don’t, and trees are lost. Are the for permission… BIOS/ VICTORIA LISTER CARLEY, OALA, A MEMBER OF THE GROUND EDITORIAL BOARD, HAS HAD HER OWN PRIVATE PRACTICE FOR fines enough? No. For people with money MORE THAN TWENTY-FIVE YEARS. OVER THE LAST FEW YEARS, SHE HAS BEEN INCREASINGLY AWARE OF THE CHALLENGES AND who want to remove houses and rebuild, PT: That’s right. There are these under- CONFLICTS REGARDING TREES IN THE DESIGNED LANDSCAPE. and the house that’s going to be rebuilt is ground “tree care” companies who come in PAUL MARSALA, OALA, IS THE FOUNDING PARTNER OF TERRAPLAN AND BRINGS MORE THAN THREE DECADES OF LANDSCAPE worth $1 million, a $10,000 fine is hardly any- on the weekends and they take trees down. ARCHITECTURE EXPERTISE AND LEADERSHIP TO THE FIRM AND ITS CLIENTS. HE IS WELL KNOWN FOR HIS WORK ON NUMEROUS thing. Compared to changing the founda- They make them disappear. HIGH-PROFILE, LARGE-SCALE URBAN DESIGN PROJECTS. tion, going through the time it would take to JANET McKAY IS THE FOUNDER AND EXECUTIVE DIRECTOR OF LEAF (LOCAL ENHANCEMENT AND APPRECIATION OF FORESTS), A NOT- get a permit to remove the trees, to get an JS-C: I’ve actually had tree companies call FOR-PROFIT ORGANIZATION THAT IS DEDICATED TO ACTIVELY INVOLVING TORONTO RESIDENTS IN URBAN FOREST STEWARDSHIP. application in and have it denied, and the me saying that they’ve been approached IN 2003, McKAY RECEIVED THE ARBORICULTURE AWARD OF MERIT FROM THE INTERNATIONAL SOCIETY OF ARBORICULTURE FOR HER cost of re-doing plans, you get more benefit by people to take trees down. The people WORK IN COMMUNITY-BASED URBAN FORESTRY. SHE SERVED AS A MEMBER OF THE BOARD OF DIRECTORS OF THE ONTARIO URBAN than the $10,000 cost. know there’s a bylaw but they don’t want FOREST COUNCIL FROM 2002 TO 2006. to go through the process, so the tree has VOJKA MILADINOVIC, B.SC.F., A GRADUATE FROM THE FACULTY OF FORESTRY IN SARAJEVO, IS AN URBAN FORESTRY PLANNER WITH Netami Stuart (NS): On the other hand, I been removed by another company, THE CITY OF TORONTO URBAN FORESTRY DEPARTMENT. SHE IMPLEMENTS THE RAVINE AND NATURAL FEATURE PROTECTION have a client who wants to develop a house and they’re sort of ratting on the BYLAW IN THE WEST PART OF TORONTO, REVIEWING TREE REMOVAL APPLICATIONS AND DEVELOPMENT APPLICATIONS. in downtown Toronto. He knows he’s going other companies.

JEFFERY SILCOX-CHILDS, OALA, A SELF-CONFESSED "TREE GUY," IS to have to do something about a tree that’s THE MANAGER OF PARKS SERVICES FOR THE CITY OF VAUGHAN WHERE HE OVERSEES THE CONTRACT SERVICES, HORTICULTURE right beside his property. Fifty percent or Janet McKay (JMK): A lot of people don’t AND FORESTRY SECTIONS. more of the canopy is overhanging his know how to get proof, to gather the evi- NETAMI STUART, OALA, IS AN ISA CERTIFIED ARBORIST AND A LANDSCAPE ARCHITECT WHO WORKS FOR THE CITY OF TORONTO. property, but the stem is not on his property. dence that you actually need for the city to

PATRICIA THOMSON IS THE MANAGER AND HEAD CONSULTANT I was able to say, listen, you can prune your successfully charge somebody. AT KELLY'S TREE CARE LTD. IN SCARBOROUGH. SHE IS AN ISA CERTIFIED ARBORIST AND HAS BEEN WORKING IN ARBORICULTURE side of the canopy, and you can adjust the FOR TWENTY-ONE YEARS. design of the house. So hire an arborist Vojka Miladinovic (VM): Also, a lot of peo- now, and do some pruning for structure, ple don’t want to confront their neighbours. knowing that in five years, after being taken Usually, when people report infractions of

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that kind where a tree has disappeared, JS-C: I get a few of those a week… down in their neighbourhood, and they they won’t necessarily stand up in a court don’t know what to do about it. They feel and say they have seen it. If a person is not PT: Most architects are knowledgeable very helpless and it is a bit of an eye opener willing to testify in court, there’s no evidence, about the bylaw and when they start a proj- in terms of education of the public that the basically. Even if a tree company goes and ect, they know that it takes x number of bylaw doesn’t stop the trees from coming removes a tree, the property owner can still months or weeks to get this portion of the down. It just puts a process in place that argue that he didn’t hire them. It’s very diffi- project done, and they know it takes at least monitors how many are coming down, cult to prove in court that the tree has been three months to get through the tree-issue where and why, and what’s being replaced. removed by the order of that person. portion, and in the ravine, it can take a year It’s not a perfect system. I think overall it’s to get through the whole process. been a positive thing, but it’s definitely not PM: So if the permit process is taking three perfect. My expectation was that the city months, what can be done to speed it up? PM: Most large-scale developers know could withhold the building or demolition there’s a process and that it can sometimes permit until tree protection was in place, VM: We are definitely short-staffed; that’s a take six months. Well, guess what? The re- but I learned it actually was not the case. chronic condition. I know that on the private zoning is going to take a year anyway, so it It’s only when they go to the committee tree side, the city of Toronto has simplified makes no difference. of adjustment that they can really do that the process of issuing permits to the point and this is a big gap. where a permit can sometimes be issued VLC: The bigger the project, the more on site. So the city is trying to deal with it in a people will expect that there are all these JS-C: For small developments, where trees proactive way. But some permits are just not sections to go through. are involved they will not issue the building that simple. Sometimes you have to write a permit until the tree permit is in place. report to a councillor, involve the whole NS: Vojka, if I submit a site plan, as a land- neighbourhood, and wait to hear if some- scape architect, does the city’s forestry VLC: It’s part of your building permit that one has an objection. And if someone has department have a department that checks you’re signed off on your tree permit. an objection, there has to be a process of the planting as well, to make sure that the consultation. The process has its course and tree is planted correctly and is watered and NS: Yes, but the hoarding isn’t unfortunately it’s designed in such a way mulched? Is there somebody from the necessarily there… that it kind of lasts. When it comes to ravine forestry department who checks that? trees, unless the tree is really, really valu- VLC: But the inspectors do drive around and able, we tend to look for replacement rather VM: The planners on the file go out and if your hoarding isn’t up, they definitely are than confrontation in most situations, or check. In the past couple of years we have on the case. some kind of net environmental benefit for included taking securities for the implemen- the site. tation of the plans that are submitted and JMK: But even when you have citizens approved. Before we return security, we reporting problems, because of work loads JMK: Sometimes the long wait has become want to make sure the planting has been and because of other factors, in my experi- a deterrent and so in that way, the lengthy done mostly according to the plan. So we ence the response has not been as quick process could actually work to save trees. do a review of the site conditions. and people get very upset. We get a lot of Some people might say, “There are existing phone calls from people who are desper- large mature trees, maybe we’ll avoid that NS: My experience in Vaughan is that ate, really desperate, and they don’t know property because we know there’s a they’re tough—they actually send somewhat to do or where to turn to save lengthy process and there will be costs.” body who knows something about trees these trees. and tells you “No, you’re not getting your VLC: Do you think that, on the whole, there’s property assumed until somebody mulches NS: Is it usually about people with chain- more public awareness, fewer trees being those trees.” saws cutting down trees or is it incursions cut down, people being more cautious? into the tree protection zone, trampling, and CITIZEN INVOLVEMENT driving stuff in? PT: Yes. From my experience, most people have heard about the tree-cutting JMK: LEAF is a community-based organiza- JMK: It’s both of those. It’s also about neigh- bylaw. We get, as the years go by, fewer tion and we were really involved in getting bours being in the process of getting a per- and fewer lectures over the phone about the Toronto tree bylaw harmonized. We mit where someone thinks they shouldn’t how unfair it is for the city of Toronto made a lot of deputations and a lot of com- get a permit. Certainly, lack of tree protec- to tell them… munity mobilization around getting support tion zones is a problem that we hear about for that. We get a lot of phone calls from quite a bit. It’s the whole question of do you people who are upset that the tree bylaw use the stick or the carrot? I don’t really think is not saving trees, that trees are coming that we have any carrots. It would be great

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to have some carrots! Could we get incen- vate tree-removal permit. They’re required fact that arborists should be consulted more tives for developers and architects and other to replant and they contact us because we often. I think a lot of the time, tree protection professionals to go that extra mile have a backyard tree planting program. measures and on-site pruning during con- and really strive to design better buildings But some people absolutely don’t want the struction and all those things that kill trees and structures and ways of doing things? replacement trees and they’re doing it sim- during construction, they happen because It’s not impossible to do. ply because they have to. Those are really there aren’t tree care professionals doing not the people we want to be serving in our the work, it’s just the guy with the bobcat, or PM: It’s called a tax break… program, because we’re looking for the the guy who knows how to make hoarding. best stewards for the trees that we plant. So I think the industry could help to educate VLC: We’ve talked a bit about bylaws, but if this is something we’re struggling with. contractors about how to preserve trees or you were to look at, say, getting permits in a what constitutes good tree preservation on new development, in what way could you JS-C: If they don’t want the tree and you site. How do you get your general contractor encourage people to behave better? know they don’t want the tree, whatever to do that? Because one thing that’s always been said they put in is not going to survive, they’ll is that it’s expensive, it adds no value to the ensure it won’t survive. So I’d rather see VLC: That would be the role of the profes- developer to follow the rules. the tree go somewhere else, within the sional, the landscape architect, architect, community if possible, in an open and planner. If you know that the developer PM: We did a project in Kitchener, a com- space, wherever. is interested, you’d have an arborist as part mercial development, where we kept this of your team, and it’s how you structure the grove of trees. It’s quite marvellous. As an JMK: Toronto has a cash option. You can consultants’ contracts. incentive, Kitchener actually reduced the pay a fee rather than replant. That’s actually parkland dedication—it’s usually 5 percent an interesting idea for a compromise. NS: It’s true, but if you have an engineering and they cut it back to 3 percent. company or a design-build company in JS-C: I’d like to see more of that happen. charge of the general contract, they call VM: Trees increase the value of the you a year and a half after they’ve finished property, especially big trees. VM: We do prefer to see the tree replanted planting the trees instead of having you on site, if there is room, but if there is no there as they are planted: “Oh, can you do VLC: But now trees are also restricting room to plant on site, we accept cash in an inspection, we need our letter of credit,” people’s ability to develop a site. lieu. But once the tree’s planted, it that kind of thing. You really are pretty becomes protected. divorced from the planting of trees, and how VM: Yes, but the canopy and the whole your plans are executed and what it looks ambience of the site increase the value. But JMK: Is there monitoring of that? like, and what the conditions are like on site. it appears that the value of the tree dramatically drops when it interferes with your VM: We do have one person who monitors VLC: This leads to the next question, which plans. I see so many situations where the plantings, but we would like to have more is, how can new trees have a better chance neighbours are complaining and the devel- people doing that. of success? We’ve already referred to this: if oper is protecting the trees, but what the somebody doesn’t want that tree to live, that neighbours are really concerned about is JMK: With LEAF’s program, we go back tree isn’t going to live. We all know people the big house that’s going up. And they and do follow-up. I think that’s one of the can make things die remarkably well. How want to use the tree protection bylaw to reasons the city recommends us a lot. They can we, though, increase trees’ chances? restrict development on the property. So I know we’re going to plant native trees, the think the mindset is different when you’re right tree in the right place. We send an PM: I think Vaughan is a good example. A building and when you’re protecting trees, arborist out to every site to decide on the subdivision may not be assumed until the and it’s hard to marry those two. Another species and the location. We do the plant- forester signs off on it. If the whole develop- thing that happens—I would say 80 percent ing and we do follow-up. So it’s a way for ment process takes three to four years, this of the time—people will convince me that the city to know that the tree has actually forces the developer to maintain the trees. they just absolutely love their tree, but… been planted. Of course, he may not maintain them properly. Some do and some don’t. PT: You know the word’s coming: “but…” THE ROLE OF ARBORISTS JS-C: The way the market is right now, it VM: As soon as I hear “I love trees,” I know NS: I think one thing that would really help in seems like people want their letters of credit what’s coming... terms of getting trees planted and planted back so we’re getting a lot more developers well on bigger sites, is to have general con- going through for assumption. JMK: We now get quite a few referrals for tractors understand what arborists do, and plantings that are required as part of the pri- why they do it, and how they do it, and the

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VLC: With the tighter economy the require- start to build a case for the need for legisla- preserve and protect what we have, then how ment is to get the money back faster. But tion at the provincial level and which Act it do we preserve and improve soil quality, then then six months later they get their money would best fall under and what that legisla- how do we plant new trees. back and nobody has responsibility for tion change would look like. those trees. NS: I’ve heard Richard Ubbens tell a room full of VM: Education is very important. I tend to landscape architects that they need to design JMK: I think community education and advise any developer that they should get subdivisions better so that trees will survive. And engagement is really key in terms of getting an arborist on site before they design foot- everybody was going, “Yeah, why don’t you tell young trees to survive—workshops, training, prints, but obviously it’s not enough. The ISA the civil engineers that, because no one ever and events—all kinds of community and the OALA could also send the same asks us how the curb is going to be designed, engagement that gets people to build their message to the developers’ community and ever!” With wonderful exceptions of innovative own skills, understanding, and knowledge eventually it will take place. Nothing is going developers, there are not many options for land- of what it takes to help trees survive. to be done if the developer is not ready to scape architects to ply their trade in the subdivi- invest the required time. And I believe the sion design department. JS-C: Simple things like door hangers when same thing applies to planting conditions, planting: “Your tree requires x amount of whether it is in subdivisions or single-family JMK: The softscape always comes last, water. Please help us out.” dwellings. If a person is not willing to carry somehow. I think that’s a common complaint the cost of the required environmental ben- with arborists as well, that they’re consulted at JMK: Another issue is soil quality, in terms of efit, then there’s not much we can do. And a the very end of the process instead of at the having young trees survive. Often, soil quali- lot of the time, the cost is actually the reason beginning when the design could actually ty is so poor that you’re limited as to what they don’t do it. be modified. you can plant in basically clay subsoil that’s been compacted by machinery, with two VLC: Well, one of the things I’ve observed PM: The landscape architect or designer could inches of topsoil put back on, and then sod. is that as we’ve developed the bigger recommend new, innovative approaches like In some cases the drainage is really horrific, machines to dig the holes and so on, it’s porous paving or bioswales. That’s coming to and then the lack of organic matter in the quicker and easier to strip the whole site, the mainstream now; it is happening, but not soil makes it really challenging to actually put all the soil there, do the work, and put it fast enough. get trees established. back. This never used to be the case, so now the whole way in which people build VLC: So the key seems to be: the earlier in the PM: One problem is that if you put all the the sites is based on really a lot of damage process that the tree is identified and profession- topsoil in the boulevard, then there’s no to the soil structure. Nobody is there on site als such as landscape architects and arborists structural support against the curb, so the to see that part of the process. You, Paul, are brought in, the better. developers are complaining that their curbs would be more likely to do that sort of work. are falling apart. Is it ever in your brief, to see how they PM: We need to be involved right at strip the topsoil? the beginning. JM: And each municipality makes their own standards in terms of details. PM: No. Very seldom. JMK: Do you think that potential changes in provincial legislation could help that? JS-C: And it’s constantly changing. VM: There has to be something in it for the developer. There has to be a carrot. NS: Yes, the more that legislation requires the JMK: And there’s no provincial legislation or work of a given profession or trade, the more coordination for any of this. There’s no men- JMK: There has to be a carrot and a stick: a that given profession or trade will be invited to tion of trees outside of the natural environ- stick for the minimum standard and a carrot do work by people who need that work to ment in the Building Code or the Planning for the higher standard. be done… Act. LEAF is actually working on this issue now. We’re working with some other part- VLC: And that’s the hard part—finding JMK: …and taken seriously. ners to look at what is the experience right the carrot. MANY THANKS TO LISA MACDONALD, ASSOCIATE MEMBER, OALA, FOR TRANSCRIBING THIS ROUND TABLE DISCUSSION. now with the municipalities in terms of challenges, successes, and pit falls with tree JMK: Eventually, ideally, as the public’s protection bylaws. And we’re going to be understanding of the value of trees and doing a survey to get information from good soil increases, consumer demand will municipal forestry contacts across Ontario to help drive change. But planting is not the whole answer to the question of how we protect and improve our urban forest. The first answer to that question is how do we

Sad Tree Challenge .05 26

Sad Tree Challenge

In Ground 03, we put out a challenge, inviting all tree enthusiasts to submit photos of the "saddest tree," including reasons for the nomination. And respond you did! We hesitate to characterize these trees as "winners." Instead, we offer this collage as evidence that trees need all the help they can get.

COORDINATED BY FUNG LEE, OALA

01/ Dundas and Ossington, Toronto

IMAGE/ Todd Irvine, LEAF 02/ Cobourg: "Its roots cannot breathe."

IMAGE/ Gina Brouwer 03/ "This tree with the split personality was planted where it had no room to grow."

IMAGE/ Gary Westlake 04/ Red maple, Vancouver: "It has endured so much in its short life."

IMAGE/ Catriona Hearn 05/ Norway maple, Toronto: "Though now an unloved species, does this tree deserve to be treated in this manner?" 01 IMAGE/ Real Eguchi 06/ Toronto: "Sad, but also hopeful because it refuses to die."

IMAGE/ Lorraine Johnson 07/ American elm, Highway 6, near the Niagara Escarpment: "A lone survivor of Dutch Elm Disease, now threatened by a highway widening project."

IMAGE/ Karen Moyer

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03 04

06 07

Sad Tree Challenge .05 28

12 13

Sad Tree Challenge .05 29

08/ Bathurst and Bloor, Toronto: "Sad, because its 'house' is falling apart around it."

IMAGE/ Lorraine Johnson 09/ Winnipeg, Manitoba: "It has a very small area for root growth surrounded by paving; the branching area is full of power lines; it has a gaping trunk wound from a former vehicle impact; it has scale insects living on its twigs; and it is suffering from dehydration from de-icing salt spray from the street."

IMAGE/ Karen Asmundson 10/ "Tree as sign post."

IMAGE/ Jim Melvin 11/ Bloor Street, Toronto

IMAGE/ Ayako Kitta and Bryce Miranda 12/ Whitby: "If you look closely, it appears that there's a tear rolling over the damage from the tree tie."

IMAGE/ Lisa Shkut 13/ Downtown Welland: "Maybe not the saddest tree out there, but a common example of unfortunate urban tree planting practices."

14 15 IMAGE/ Sara Taylor 14/ Red maple, Vancouver: "While the restoration of the adjacent heritage building has been celebrated as visionary, this tree stands in silent testament to our apparent blindness to the urban forest."

IMAGE/ Catriona Hearn 15/ Nathan Phillips Square, Toronto: "A grand life cut short for human consumption in the guise of celebration."

IMAGE/ Marlise Eguchi 16/ Whitby

IMAGE/ Lisa Shkut

IF THE SAD TREE CHALLENGE HAS WHETTED YOUR APPETITE FOR VISUAL TREE LORE, VISIT THE GROUND SECTION OF THE OALA WEBSITE (WWW.OALA.CA) FOR LISA DOBBIN'S FEATURE ON "WEIRD TREES" FOUND IN ONTARIO.

Letter From… .05 30 London The Would-Be Capital’s Canopy

Putting the forest back in Ontario’s Forest City

TEXT BY ALEXANDRA HOSSFELD, ASSOCIATE MEMBER, OALA

Growing up in London, Ontario, I was lucky enough to live by the London that will benefit by systematic and concerted tree plant- edge of Warbler Woods, an environmentally sensitive area man- ing.” The Urban League and the various partners that collaborated aged by the Upper Thames River Conservation Authority (UTRCA). to develop the StraTreegic Plan, including the City of London, From my house, I could hike the nearby ski hill, and see the city devised a four-part hierarchy of ecological restoration, which uses stretching for kilometres through a sea of upland deciduous trees. tree planting as a foundation for improving ecological linkages and biodiversity within the city. The hierarchy is based on activities On lower ground, however, it’s apparent that the so-called Forest that engage the community in planting trees first at the private City isn’t living up to its epithet. The legacy of the Forest City, nick- level, expanding to street trees at a neighbourhood scale, treeing named after John Graves Simcoe attempted to create the capital city parks and public property at a community scale, and finally of Upper Canada in the forest at the forks of the Thames River, has linking the larger bioregion by reforesting natural watercourses become somewhat ironic as the total forest cover has fallen to 10 and wetlands. percent. London lags far behind Ottawa at 30 percent, and Toronto at 20 percent. Even Kitchener-Waterloo, which conjures The StraTreegic plan is a vision that builds on the previous efforts associations of innovation and technology as opposed to images of several organizations. It has identified hotspots that are most in of woodlands, surpasses London in forest cover. need of attention, has an action plan for reconnecting those hotspots to the greater urban forest network and beyond, and has Trees of the Forest City continue to be threatened by pests both allocated volunteers to overcome limited financial resources. large and small. “Pests” include the emerald ash borer, which has been discovered in trees at Springbank Park, and a much more The City of London’s forestry programs division is involved in an formidable opponent: development. An article published by the ongoing effort to infill established neighbourhoods throughout London Free Press this past December describes how London London with trees where space permits. Concurrently, the City initi- developers have won the right to legally challenge the City’s pro- ated two projects targeting the urban forest this past summer. tection of local woodlands, which was recently enhanced to make One involved the UTRCA in spearheading a study that used the it easier to classify woodlands as ecologically sensitive. The ruling Urban Forest Effects Model (UFORE), a software modeling program in favour of the developers puts forest areas the size of 1,000 foot- developed by the United States Department of Agriculture Forestry ball fields at risk, and further threatens tree cover in the city. Service. UFORE provides a standardized method of calculating structure, environmental effects, and value of the urban forest. In Although prospective development seriously jeopardizes London’s London, participant landowners were asked for access to their trees, several ongoing projects headed by various local organiza- properties, and field crews collected data on resident trees that tions are focused on re-establishing forest cover in the Forest City. represented a sample of the total tree cover in London. This data One such group is ReForest London, which has partnered with the will help stakeholders target the areas in need of improvement Urban League to launch their StraTreegic Plan, an initiative that when it comes to protecting local woodlands. aims to “address current and long-term needs for a healthy

Letter From… .05 31 London

01 The Tree Watering Kit Project, also initiated this past summer by the City in partnership with ReForest London, was aimed at increasing awareness of the environmental roles city trees play, and the responsibility of citizens in keeping them healthy. Five- hundred watering kits were distributed to Londoners who recently received new trees in the boulevards in front of their homes. The kits consist of information regarding the project, as well as a recycled 20-litre bucket, to be placed at the base of the tree to allow water to slowly seep out of holes drilled in the bottom. The buckets hold enough water to supplement the tree roots for one week during periods without rainfall.

Although the results of the UFORE study and the Tree Watering Kit Project are yet to be published, the projects themselves are evidence that local stakeholders are aware of the irony of the Forest City, and are setting goals to restore its legacy. Not only do the projects benefit the urban forest and restore linkages to regional 02 natural systems, they provide opportunities for social programming, benefiting the community. For instance, the Tree Watering Kit Project was assisted by youth from lower income neighbourhoods within London, providing job opportunities and experience.

Despite the meagre forest cover in London, there is still hope for the “De-Forest City,” as my dad likes to joke. When I climb the hills 01/02/ Volunteers planting trees at the Elsie Perrin Williams west of town and look out over the city, I think that if Simcoe could Estate, a project that is part of the "10,000 Trees for the see what I see today, he still would have chosen this scenic land- Medway," which aims to naturalize the corridor along scape for the capital of Upper Canada. the Medway Creek in London BIO/ ALEXANDRA HOSSFELD, ASSOCIATE MEMBER, OALA, IS A RECENT GRADUATE OF THE BLA PROGRAM AT THE UNIVERSITY OF GUELPH, AND IS CURRENTLY LIVING IN THE FOREST CITY. IMAGES/ ReForest London

Plant .05 32 Corner

Branching Out

Some unusual trees that deserve to be planted TEXT BY LORRAINE JOHNSON Surveying a typical street scene or peering into the back yards of more often most homes, one would be forgiven for thinking that there are very few tree species that actually grow in Ontario. Many factors have led to the relatively limited tree palette that tends to domi- nate our communities. Nurseries favour species that are well known, in demand, and economical to produce; municipalities promote proven survivors hardy in harsh urban conditions; and many landscape architects, designers, and contractors look for species that are readily available. The result, not surprisingly, is a relative lack of species diversity—Freeman’s maple, linden, and honey locust immediately come to mind.

However, if you’re looking for more unusual tree species for southern Ontario, the following are some relatively forgotten (or, at least, underused) gems to consider.

Paw Paw (Asimina triloba): Native to the Carolinian zone of southwestern Ontario, paw paw is guaranteed to spark interest and conversation. This tree produces the largest edible native fruit in Canada: it looks like a mango and tastes like a cross between banana and pineapple. The leaves are likewise tropical looking— large and luxurious. Small maroon flowers cover the branches in spring, before the leaves appear. Very easy to grow, paw paw does well in shade and sun, and reaches approximately 7 to 10 metres. It does not tolerate windy sites. To ensure fruit set, plant at least three trees for cross pollination. A wildlife benefit of this tree is that paw paw leaves are the preferred food for the larvae of the rare zebra swallowtail butterfly.

Kentucky Coffee Tree (Gymnocladus dioicus): Increasingly used as an ornamental (indeed, the city of Toronto now makes it available for free front-yard planting), Kentucky coffee tree has many unique and attractive features. Its doubly compound leaves are the

01/ Cucumber magnolia largest of any native tree. Its bark is distinctively scaly and its twigs

IMAGE/ Andrew Leyerle knobbly. Although the flowers are not showy, the fruit—large 02/ Tulip tree brown pods that hang on the tree throughout the winter—are IMAGE/ Andrew Leyerle 03/ Paw paw attractive. Kentucky coffee tree requires sunny conditions, does

IMAGE/ Andrew Leyerle well in a wide range of soils, from sand to clay, and is especially useful in difficult conditions.

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02 03

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Tulip tree (Liriodendron tulipifera): A signature species of Carolinian forests, tulip tree can take your breath away in spring, when the tree is covered in large yellow flowers, and again in autumn, when the leaves turn a glowing yellow. The tree’s “tulip” name is doubly appropriate: the yellow flowers with orange bases resemble tulips, as do the four-lobed leaves in profile. Fast growing and reaching 30 metres, young trees require sunlight, but as they get older tulip trees are shade tolerant.

Redbud (Cercis canadensis): This relatively small tree (up to approximately 7 to 10 metres tall) is highly ornamental in spring— small, showy pink flowers cover the branches before the leaves appear. It behaves somewhat like a shrub, often with multiple trunks and a low canopy, though it can be pruned to more of a tree form. Leaves are heart-shaped, and the fruit is a purplish, flat pod. Redbud is adaptable to a broad range of conditions, from sun to shade, dry to moist soils, sand to clay.

Shagbark hickory (Carya ovata): Shagbark hickory is a tree that teaches patience. Its deep taproot means that large specimens are often difficult to transplant, so it’s best to start small; yet it grows very slowly. Think of it as a planting for the future, and imagine the joy someone else will have collecting (and eating) the sweet-tasting hickory nuts years ahead. Growing to approximately 25 metres, and long lived, this hickory’s most distinctive feature is the shaggy bark of mature trees. Best grown in sun to part sun, it is adaptable to dry or moist conditions, sand to clay.

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Hoptree (Ptelea trifoliata): The natural habitat of hoptree provides clues to its very tough, resilient character: it grows in the windswept, changing conditions of the Lake Erie shoreline, buffeted by wind, anchored in sand. Reaching 8 to 10 metres, it grows quickly, with crooked, gangly twigs. Flowers cover the tree in early summer with white clusters; the fruit is equally attractive, with papery disks that hang in clusters. The leaves are comprised of three leaflets and provide food for the larvae of the rare giant swallowtail butterfly. Hoptree grows best in sunny, open conditions, and is adaptable to sand or clay.

American Plum (Prunus americana): As showy as any ornamental 06 plum, this native tree is covered in white to pink, fragrant blossoms in spring, providing nectar for insects. The fruit, which ripen in summer, are edible, if somewhat more sour than their cultivated relatives. A small tree, growing to approximately 3 metres, American plum prefers sun and well-drained conditions.

Black Gum (Nyssa sylvatica): Although this tree is not well known in Ontario, many people prize a product that is sourced from it—or, rather, from bees nectaring at its blossoms: tupelo honey. Black gum requires sandy, acidic soil, and sun. It grows slowly, to approximately 15 metres. The flowers are not showy, but its small, blue-black fruit is attractive to birds and mammals. Striking features include the tree’s deeply fissured bark, which is often compared to alligator skin, and the spectacular fall colour—anywhere from yellow and orange to scarlet and purple.

Chinquapin Oak (Quercus muehlenbergii): Unlike most oaks, which are slow growing, chinquapin oak is a fast-growing tree. It reaches 10 to 20 metres, and is very tolerant of urban conditions, making it a good street tree. Its leaves, also unlike other oaks, are un- 04/ Cucumber magnolia lobed and resemble the true chestnut (Castanea). It grows best in IMAGE/ Andrew Leyerle sun, and tolerates drought and sandy or clay soil. 05/ Redbud

IMAGE/ Mathis Natvik 06/ American plum Cucumber Magnolia (Magnolia acuminata): The only magnolia IMAGE/ Mathis Natvik native to Canada, cucumber magnolia is a stately, tall-growing (to 30 metres) tree. Its yellow flowers appear in spring, followed by fruits that turn red in early autumn. Growing in sun or shade, it prefers slightly acidic to neutral soil.

A caveat: many of these species take work to track down. To find nursery sources, consult the Society for Ecological Restoration’s 2007/2008 Native Plant Resource Guide (see www.serontario.org). A very useful source of information on the trees listed above is the book Trees of the Carolinian Forest: A Guide to Species, Their Ecology and Uses, by tree expert Gerry Waldron.

BIO/ LORRAINE JOHNSON'S MOST RECENT BOOK IS A COLLECTION OF ESSAYS, THE NATURAL TREASURES OF CAROLINIAN CANADA.

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TEXT BY NANCY CHATER, ASSOCIATE MEMBER, OALA

Planting Tree Urban A quiet revolution has begun below the Structural Soil surface of the city. The competing conditions required for tree root growth, on the The term “structural soil” is used for soil one hand, and standard construction of mixes that are engineered to provide infrastructure, on the other hand, are structural support for paving while main- being reconfigured into a more coopera- taining porosity. The term was coined by tive below-grade environment. We can the inventors of CU-Structural Soil at look forward to long-term health of the Cornell University’s Urban Horticulture urban canopy as a result. Institute led by Dr. Nina Bassuk in the early 1990s. Patented in 1998, CU-Structural Soil The increasing use of relatively simple but has been used in more than 500 applica- transformative technologies such as struc- tions in Canada and the US. Comprised of tural soil, soil cells, and bridging sidewalks 80 percent crushed stone (with no fines) are facilitating the redesigned relationship and 20 percent soil (clay loam to maximize between trees and infrastructure. The key water and nutrient holding capacity) with is that these materials carry the structural a small amount of hydrogel to prevent loading of the city’s paved armature— separating, CU-Structural Soil forms a rigid roads, sidewalks, plazas, parking— lattice of angular stone that carries the removing the need for typical compacted load, with open voids between the stones base materials and allowing for uncom- to allow the soil to remain uncompacted. pacted soil in the critical 60 centimetres Tree roots can grow freely while the below grade where 90 percent of tree movement of water up and down is root biomass is located. unimpeded. As a result of the drainage patterns, moderate to highly drought-toler- Rethinking the relationship between ant trees should be used. CU-Structural utilities and tree roots is the other big Soil is meant to be used under paving area of change within this revolution in and can be installed adjacent to regular design below the ground. Clustering the soil in open tree root areas. It can provide pipes and cables of utilities together, plac- effective bridging between soft landscape ing them well below the primary root areas so that tree roots can grow growth horizon, and even rethinking the laterally below paving in a continuous placement of utilities altogether, are inno- course, helping to achieve the larger vations that recognize the long-range soil volume upon which tree health planning required for sustained urban and longevity depend. canopy health. Clearly, the advantage of combining load- bearing support with useable soil is tremendous. As a recent technology, CU- Structural Soil is still being tested for long- term results. Questions remain as to the effect of the organic matter becoming depleted over time and whether the voids between the crushed stones remain open. The pH of the crushed stone, generally limestone or granite, has an impact on soil pH, and tree choices have to be made accordingly. The cost is approximately three times that of topsoil. Perhaps the

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main limitation of CU-Structural Soil is that This innovative technology comes with an only 20 percent of the mix is soil. This is upfront cost, as a Silva Cell costs about significant in light of the City of Toronto’s $300-$500 per cubic metre (installed). The goals to achieve 30 cubic metres of soil labour portion of the cost is expected to per tree. come down as contractors become more familiar with the process. CU-Structural Soil Cells Soil costs about $150-$200 (installed). If one compares actual soil volume, Silva There is rapidly growing interest in the soil Cell is less expensive (since only 20 per- cell system by Deep Root, designed in col- cent of the structural soil profile is soil). laboration with landscape architect James Clearly, the investment has to be weighed Urban, called the Silva Cell. This modular against long-term operational costs and matrix of stackable cells (made of fibre- tree survival rates, which are tied to the glass and polypropylene compound with a enormous economic and environmental galvanized steel-reinforced top deck) pro- values of the urban canopy. vides the necessary structural support for paving while the cells are filled with Bridging Sidewalks uncompacted soil. Significantly, more than 90 percent of the system is viable growing The bridging sidewalk is a construction medium, and the soil type is flexible. The method employed in conjunction with design accommodates space for oxygen trench planting for urban street trees. 02 between the finished grade of soil inside Roncesvalles Avenue and University the cell and the top deck of the cells. The Avenue are examples of this in the City of Silva Cell system also functions as a biore- Toronto, where raised street tree planters tention system for stormwater. with open bottoms are located parallel to the road. Between the planters is a bridg- Across Ontario, about twenty-five projects ing sidewalk comprised of two curbs run- are actively considering the Silva Cell sys- ning parallel to the street, which support a tem, while three major projects in Toronto, slab overtop for pedestrian circulation. The which are using soil cells, are underway planting trench runs beneath the entire including the Bloor Street Revitalization and length of the planters and bridging side- Waterfront Toronto’s East Bayfront and walks, providing continuous soil volume for Central Waterfront public realm initiatives roots to spread laterally. Air space is left (streetscapes and promenades) as well as between the slab and the soil below for the West Don Lands. James Roche, OALA, vital oxygen exchange. Vented pipes for Senior Project Manager with Waterfront air flow are integrated into the bridging

03 Toronto, notes that maximizing soil vol- sidewalk. City Forester Richard Ubbens For more information on CU-Structural Soil, ume, providing structural support for notes that this planting detail could be visit http://www.hort.cornell.edu/UHI/outreach/csc/city_trees.pdf. For Silva Cell information, see http://www.deeproot.com/. paving, and the ability to organize utilities combined with soil cells underneath a por- are the advantages of soil cells. Arborist tion of the regular sidewalk closer to the and OALA Associate Member Joe McLeod building wall, with an oxygen connection 01/-03/ A modular matrix of stackable cells provides of the Planning Partnership, who is work- linking the trench to the field of soil cells. structural support without compacting the soil. ing on the West Don Lands streetscapes, BIO/ NANCY CHATER, ASSOCIATE MEMBER, OALA, IS A DESIGNER AND PROJECT MANAGER WITH MARK HARTLEY IMAGES/ Deep Root Partners, LP notes that the Silva Cell module cannot be LANDSCAPE ARCHITECTS IN TORONTO, AND THE TECHNICAL CORNER COLUMNIST FOR GROUND. cut and in some instances the particular size (60 cm x 120 cm x 45 cm) and geometry make it advantageous to combine soil cells with structural soil, with the structural soil acting as a bridge to accommodate turns and the interface with some utilities.

Notes .05 38

Notes: competition The City of Toronto has declared Toronto- based gh3 the winner of the June A Callwood Park Design Competition, as recommended by the competition jury. 02 Deriving form from the sound waves of Miscellany Ms. Callwood’s voice, the design of this art 0.4-hectare park proposes a “Super Real Forest” as a strategy for enhancing For thirty years, London, Ontario-based artist of News Toronto’s tree canopy and contributing to Ron Benner has been making garden the functioning and structural aspect of the installations, using plants, seeds, signs, and city’s urban core. To learn more about photographs to critique the political, social, and June Callwood Park and the design com- cultural, economic, and environmental con- petition, visit http://www.toronto.ca/parks/ sequences of colonialism. And, not inciden- June_Callwood_Park/index.htm. tally, to create gardens that are as lushly Events beautiful as they are full of verdant provoca- tion. A recent publication, Gardens of a Colonial Present, documents Benner’s numerous garden projects. Published by Museum London, the book includes essays by critics and curators and a wide-ranging rumination by Benner on the issues that propel his art, and the ideas, people, and travels that have influenced him. To order the book, contact ABC Art Books Canada at [email protected].

grants

The Ontario Ministry of Natural Resources and Evergreen have launched a grant program designed to support the planting of 01 100,000 native trees on publicly accessible

01/ The voice wave form—taken from lands in cities and towns across the June Callwood's last interview— creates a number of glades or courses province. The core values of this program clearings in the June Callwood Park’s design scheme. are community engagement and ongoing

IMAGE/ gh3 The University of Guelph’s Office of Open stewardship: all projects must be open to 02/ A recent book documents artist Ron Benner’s garden projects. Learning offers more than two dozen 12- members of the public and be situated on

IMAGE/ John Tamblyn week courses in horticulture, landscaping, publicly accessible lands. This program will 03/ An exhibition at the Design Exchange in Toronto explores and turf management. These courses, provide funds to public agencies, institution- design and urban agriculture. facilitated by academic or industry profes- al landowners, and community organiza- IMAGE/ Design Exchange 04/ The Ft. Wright, Kentucky, sionals, help professionals advance their tions undertaking volunteer-driven tree Sanitation District No. 1 won a 2007 GRHC Award of Excellence careers while studying from the comfort of planting projects in 2009. Grants awarded for their green roof. Training courses for design and installation their work or home. All that is required to will range from $5,000 to $15,000. There professionals are advancing the green roof industry. participate is a computer with Internet is no deadline to apply; applications will

IMAGE/ Green Roofs for Healthy Cities access. For more information, visit be accepted and processed on an www.horticulturecertificates.com or ongoing basis. For information, visit call 519-767-5000. www.evergreen.ca.

Notes .05 39

greening

In 2008, London, Ontario—the Forest City—got a little greener with a bequest from the estate of Beryl Ivey to ReForest London. The environmental organization received $250,000 to establish an endowment and continue its tree planting programs in London. The majority of this gift will be used to establish the Beryl Ivey Community and Corporate Stewardship Endowment. Through the endowment, ReForest London will continue to empower community groups along with the corporate sector to improve their community 04 and environment through volunteering, planting trees, caring for trees, and fund- accreditation ing a healthy urban forest for generations to come. For more information, visit Green Roofs for Healthy Cities (GRHC), the www.reforestlondon.ca. trade association for the green roof industry in North America, is pleased to announce the launch of the accredited Green Roof Professional (GRP) program. health The first accreditation test is scheduled for Economic arguments about the value of the GRHC Annual Conference and Trade trees can be persuasive catalysts for tree Show being held in Atlanta, Georgia, from planting efforts. Quantifying the social ben- June 3-5, 2009. The test will be based on efits of trees is also important, and social the content of the four core green roof science research is providing the data. 03 training courses offered by GRHC and Some of the most often cited research has available on an ongoing basis across been generated by Dr. Frances Kuo and exhibition North America. For a full training schedule, associates at the University of Illinois at visit www.greenroofs.org. A new exhibition at the Design Exchange Urbana-Champaign. Kuo’s Human- in Toronto explores the role of design pro- Environment Research Laboratory (HERL), fessionals in relation to the food systems green roofs founded in 1993, and the more recent of cities, and the impact that agricultural Landscape and Human Health Laboratory (LHHL) focus on the relationship between issues have on the design of urban Toronto is hosting the North American human health and greenspace. In a spaces and cities. “Carrot City: Designing debut of the World Green Roof Infrastructure Chicago study, Kuo found that trees help for Urban Agriculture” uses case studies Congress from October 19-22, 2009. poor inner-city residents cope better with such as the Green Arts Barns project in Focused on green roofs and wall infra- the demands of living in poverty, feel more Wychwood Park (Toronto) and the Edible structure design as a global solution to hopeful about the future, and manage Campus project at McGill University climate change, the congress will bring their problems more effectively. For infor- (Montreal) to illustrate innovative food landscape architects, architects, construc- mation about Kuo’s research, visit production approaches in urban con- tion professionals, and researchers from www.herl.uiuc.edu. texts, and to address the question: what around the world to discuss innovative is the place of food in the city? For more policies and programs that support the information on the exhibit, which is on dis- creation of green urban spaces. For play until April 30, 2009, visit www.dx.org. more information on the event, to be held at the Allstream Centre, Exhibition Place, Toronto, visit www.citiesalive.org.

Notes .05 40

pests innovation conference

Scientists with the Canadian Forest Service When Spacing magazine launched its The Canadian Society of Landscape have started a trial campaign against the thinkToronto urban design ideas competi- Architects/Association des architectes emerald ash borer in London, Ontario, tion, it asked people 35 years and younger paysagistes du Canada invites you to the using a new organic pesticide. The chemi- to answer the question, "If the next genera- Sheraton Centre in Toronto, Ontario, to cele- cal, which has yielded positive results in tion of urban innovators were given carte brate the 75th anniversary of the founding of applications in the United States and blanche to redesign or tweak Toronto, what the profession of landscape architecture in southwestern Ontario, is derived from the would our city look like?" More than 100 Canada. Mark your calendar now for neem tree. It has no known negative teams took up the challenge, and the win- August 13-15, 2009. effects on other animals or plants. The dis- ners—twelve finalists and eight honorable covery of several afflicted trees in London mentions—range from the strikingly simple The event promises to be a memorable has been a blow to the ongoing struggle to the elusively complex. To view the work one. The historical roots, the current state to prevent the further spread of this pest. of these passionate city builders, visit of the profession, and an exploration of our The approach recommended by the www.spacing.ca/thinktoronto, or order a future will all be discussed through a series Canadian Forest Service to deal with the hard copy of Spacing's fifth anniversary of workshops, sessions, panel discussions, ash borer’s arrival in London is to treat as issue (Fall 08 - Winter 09). and tours. Experts from across the country many of the city’s “high-value” trees as together with thought-provoking keynote possible. For more information, visit speakers will challenge and stimulate our www.inspection.gc.ca. books understanding of landscape architecture.

To register, contact Ms. Khadijah Jamal If you’re looking for one handy reference at (416) 595-1414 X 225 or library book that covers everything to do with [email protected]. planting trees in the urban environment, OALA Council has undertaken a library look no further than the recently published expansion program to assist Associate Up By Roots: Healthy Soils and Trees in the Members and other exam candidates in Built Environment. Written by landscape infrastructure their preparation for the LARE. The goal of architect James Urban and published by the program is to have at least two copies the International Society of Arboriculture, A new report from Ecojustice (formerly of each reference book on CLARB’s LARE this 479-page, voluminously illustrated Sierra Legal) makes a compelling case for Recommended Reading List, allowing for guide presents the best-available informa- incorporating green infrastructure into one reference copy to remain in the OALA tion on how to ensure that trees are pro- urban design as a strategy to reduce com- library at all times. (Some of these books are vided with everything they need to reach bined sewer overflows. “Green Cities, difficult to access and some are out of print.) their full potential. Based on the idea that Great Lakes” argues that one of the “the success of a tree is fundamentally largest single sources of water pollution in Please consider donating your reference linked to the soil in which it grows,” the the Great Lakes Basin is the combined books to the OALA library. Each book con- book begins with the science of trees and sewer pipes that, during heavy rainfalls, tribution will be acknowledged with a soils in Part 1, then moves into practical release municipal sewage and stormwa- bookplate inserted inside the front cover, strategies of applying this science through ter directly into local water bodies. Using with thanks. ten priniciples (for example, “preserve and case studies from Ontario cities such as reuse existing soil resources” is Prinicple 3, Windsor, Kingston, Toronto, and Hamilton, Visit the OALA website (www.oala.ca) to “respect the base of a tree” is Principle 5). the report outlines some of the most effec- view an up-to-date list of required CLARB- Written for a design audience, the goal of tive methods of reducing stormwater LARE reference books. To make arrange- Up By Roots is to provide “sufficient knowl- flows: green roofs, downspout disconnec- ments for a book pick-up, contact Aina edge of soil science, urban soils, and tree tion, rain barrels, permeable pavement, Budrevics, OALA Coordinator, at (416) 231- biology to make daily decisions during the vegetated swales, rain gardens, and 4181 ext. 1 or by email, course of a project.” To order a copy of this [email protected]. indispensable resource, phone 1-888-463- 2316 or email [email protected].

Notes .05 41

preservation/enhancement of urban forests. Of the latter, the report notes, “An increase in tree cover from 25 to 50 percent on a residential lot can reduce runoff from about 10 to 20 percent.” For a copy of “Green Cities, Great Lakes,” visit www.ecojustice.ca. new members

The Ontario Association of Landscape Architects is proud to recognize and welcome the following new full members to the Association:

Vicki Armitage Heidi Baillargeon * Amy Bennewies * Jeff Bruin Christopher Canning Johanna Evers * 05 Adriaan Geuze landscape conservation guidelines Francois Hebert * in memoriam for Parliament Hill; a cultural landscapes Glenn Herman video for Parks Canada; and the execu- Wing Wai Hui * JOANN LATREMOUILLE: A TESTIMONIAL tion of numerous studies, including Sarah Koeppe BY JOHN ZVONAR Government House in Regina, the Julie Michaud Cascades of Time Gardens in Banff, Salisha Price * I met Joann Latremouille in 1989, when I Neubergthal street village in Manitoba, Anne-Claude Schellenberg was not long out of school. In spite of the and Buxton Settlement in southwest Netami Stuart * generation gap, we hit it off, and our paths Ontario. The inclusion of a First Nations Lisa VanderVliet * continued to cross over the next few years. component was always a part of her Xuan Wang Joann secured a position at the Heritage clearly defined approach. In my mind, Conservation Program (of Public Works) Joann’s legacy is undoubtedly her Asterisk (*) denotes a Full Member and, eventually, I also took a position contribution to the recent Standards not having custody and use of the there. In the realm of heritage conserva- and Guidelines for the Conservation Association seal. tion, Joann found her voice. She exhibited of Historic Places in Canada. a mature poise and comfort level in working through the oftentimes challenging Closer to home, Joann had an unfettered conservation process. Joann was tireless enthusiasm for the heritage orchard she in her pursuits and unequivocal in created on her rural property. Personally, her advocacy: she literally left no I have lost a mentor, a muse, a steady stone unturned. hand at the wheel: someone who encouraged the rest of us to explore to Joann was a superb thinker and an our potential. even better writer—clear, precise. She employed all of her accumulated skills in

the protection of cultural landscapes. 05/ Joann Latremouille

While there were many accomplishments, IMAGE/ John Zvonar Joann’s most notable included: historic

Interested in being involved with Ground: Landscape Architect Quarterly?

The OALA Editorial Board is looking for volunteers who can help out with various tasks, such as research, transcription, and writing. Any level 05 of commitment is appreciated, from researching upcoming events for the Notes section to transcribing Round Table discussions...

Fun, satisfying work—and the best part, no need to attend meetings!

To get involved, please e-mail [email protected].

Artifact .05 54 Writing with Wind

Trees trace their signatures in the work of artist Tim Knowles

02 04 Using drawing implements tied to tree branches, Tim Knowles’ images in the Tree Drawings series record on paper the effect of wind on trees. Each drawing becomes a kind of signature, revealing much about the different qualities and characteristics of the particular tree species: the light touch of a willow’s relaxed, flowing line, for example, or the stiff, scratchy, neurotic marks of a spiky hawthorn.

The Tree Drawings are just one part of Knowles’ wider practice, which uses

03 chance in the production of the work. Generated by apparatuses, mechanisms, or systems beyond the artist’s control, 01/-04/ Artist Tim Knowles’ Tree Drawings utilize trees in the production much of the work seeks to reveal the hid- of drawings. den, or otherwise unnoticed motion of IMAGES/ Tim Knowles objects: the full moon’s reflection on undu- lating water, the motion of a parcel travel- ling through the postal system, or the intri- cate movement of one hundred weeping willow branches.

BIO/ TIM KNOWLES LIVES AND WORKS IN LONDON, ENGLAND. HE STUDIED AT BATH COLLEGE OF HIGHER EDUCATION AND HAS EXHIBITED WIDELY IN THE UK AND INTERNATIONALLY. HE WAS COMMISSIONED BY THE CONTEMPORARY ART SOCIETY AND THE ECONOMIST TO 01 PRODUCE A NEW WORK FOR THE ECONOMIST PLAZA IN FEBRUARY 2008 AND IS CURRENTLY COLLABORATING WITH THE ROYAL MAIL ON AN AMBITIOUS SERIES OF NEW WORKS DUE FOR COMPLETION IN EARLY 2009. FORTHCOMING SHOWS INCLUDE BITFORMS, NEW YORK, USA, AND PLYMOUTH ARTS CENTRE, UK.

FOR MORE INFORMATION, VISIT WWW.TIMKNOWLES.CO.UK.