Aerial Dusting Saves Muskoka’s Hemlocks PART ONE
Boyer's Modern History of Muskoka
This saga of Muskoka’s modern history is about a dramatic 1920s mash-up of nature and technology: caterpillars destroying trees and airplanes bombing them with poison in a desperate attempt to save Muskoka’s vacationland beauty and economy.
Muskoka’s Majestic Hemlocks
The Muskoka lakeland owes its natural allure to crystalline waters, irregular hulking islands of the planet’s oldest rock, and dense pine, hemlock, and cedar cloaking endlessly jutting shorelines. Indigenous peoples and vacationers alike saw this evergreen woodland with different eyes than lumbermen and industrialists keen to exploit it commercially. The first group cherished trees standing as a holistic forest with which they bonded in different ways. The second clear-cut trees for saw-wood and, in the particular case of hemlock – the focus of this program – for its bark, because its rich supply of tannins is needed to make leather. In 1927 both groups, despite profound differences as tree huggers and tree harvesters, found themselves uniting against a common enemy – whatever was killing off Muskoka’s majestic hemlocks.
These trees are integral to the District’s forest landscape. The robust hemlocks’ sweeping lush boughs complement the stately pines and soft dense cedars. This compelling scene of nature had been painted, photographed, and promoted as vacationland Muskoka’s “true North” experience. So in the summer of 1927, as hemlocks around Muskoka’s lakes began to lose their needles entirely, leaving forests standing like ugly naked corpses, the calamity panicked resort owners and their holidaying guests and the District’s hundreds of cottagers.
Ravages of the Hemlock Looper
The adult Lambdina fiscellaria, commonly called the hemlock looper, is a moth of the family Geometridae. In North America the looper is found across Canada from the Pacific to Atlantic coasts, and south into Pennsylvania, Wisconsin and California, wherever the trees it dines on grow. This moth is a creamy grey colour, distinctive with dark lines across its scalloped wings and long feathery antennae. The looper takes wing from August to early October, when she lays countless tiny eggs on a variety of surfaces, such as the moss and lichens growing on hemlock bark. The eggs overwinter on the tree trunks, then hatch between late May and mid-June. The hatched larva – the caterpillar stage of the looper’s life cycle – are easily identified by such markings as intricate stripes along their bodies and small black spots.
At this stage the looper becomes an overwhelming forest presence, vast armies of caterpillars munching away voraciously, causing extreme defoliation of their host hemlocks. Recently hatched young larvae eat only the delicate new foliage of spring, while earlier hatched ones now mature tackle the stronger older needles. Between them both, they devour everything, then move on to the next hemlock, leaving the woodland a baren scene of devastation – sort of resembling a forest fire without the burning.
“Something was amiss in Muskoka”
Here are the opening lines by Mark Kuhlberg, Laurentian University’s leading forest historian, in his important new book this year about Canada’s aerial war against forest pests, describing that 1920s summer when Muskoka’s hemlock trees came under unprecedented assault:
“Something was amiss in Muskoka, one of North America’s most cherished and exclusive recreational paradises, and authorities were at a loss as to how to deal with it. Local cottage and lodge owners and summer vacationers were growing more anxious by the minute as their picturesque landscape was being ruined.”
Laurentian University professor Mark Kuhlberg’s new book, entitled Killing Bugs for Business and Beauty and published by University of Toronto Press this year, explores the beginning of Canada’s aerial war against forest insects, the campaign to save Muskoka’s hemlocks, and how a tiny handful of individuals created a made-in-Canada solution to the forestry crisis.
Well, what these seasonal and full-time Muskokans did was summon Ontario forestry officials. Their investigation revealed the cause to be millions of tiny “hemlock loopers.” When the panicked Muskokans demanded what the government was going to do about them, the foresters’ reply was that it was “not physically possible” to kill bugs in forests. In this dire moment, it appeared the end of Muskoka’s vacation economy was at hand.
But not without a fight. Resolute seasonal Muskokans around Lake Joseph – mostly millionaire businessmen accustomed to getting their way, men able to find new solutions when necessary, captains of industry and commerce unrelenting in summoning help from any quarter when needed – were not about to yield their prized lakeland retreats to caterpillars. So the real drama begins.
A Perfect Storm of Nature, Culture, Economics, Aesthetics, and Politics
Events that meteorologists in 1936 began calling “a perfect storm” – referring to weather – in 1927-29 applied to Muskoka’s environmental and politically stormy phenomenon of diverse elements combining in a unique way at a single place all at once.
First, after the Great War Ontario’s new Farmer Government created a modern Department of Lands and Forests which in turn formed a provincial air service that through the 1920s began to enhance forest management by better detection and fighting of forest fires, then continued, in concert with forestry interests and logging companies, to confront the costly devastation of forest insects. After conducting a series of trials with specially adapted aircraft bombing infested woodlands with chemical dusts that were highly toxic to the pests, their new aerial dusting technique pushed Canada in the limelight internationally for having developed an effective weapon to prevent insects from destroying valuable forests.
Used in Nova Scotia’s forestry dusting trials of 1927, the Keystone “Puffer” (seen here) was pressed into service bombing Hemlock loopers in Muskoka with toxic dust in a mission pilots considered “suicidal” because of the aircraft’s many shortcomings for this inherently risky work. To be dealt with in PART 2 of this saga, “Aerial Dusting Saves Muskoka’s Hemlocks.”
Second, this aerial dusting was to protect forests for logging and commercial benefit. No forester considered how the same weapon might save forests for the aesthetic enjoyment of tourists and cottagers – the very definition of Muskoka’s highly localized vacation economy in which forests were essential. The two goals seemed miles apart. Canada’s forest industry, especially the pulp and paper makers, conceived of trees “as harvestable commodities they sought to protect until they could cut them all down to process into wood products.” Muskokan conservationists “viewed trees collectively as an aesthetic commodity that only retained its value if it remained standing and in a healthy state.” Although these traditional rivals in forest-use are diametrically opposed, Muskoka’s well-honed pattern of bridging differences between metropolitan values and hinterland practices would lead to a first-ever aerial war against insects that benefited both.
Loud Voices of the Prominent and Powerful
Third, those wanting protection for their idyllic forests, being among the most powerful of people, became a relentless force stirring up this storm. Cottage owner George Freemantle, told Ontario’s Minister of Lands and Forests, William Finlayson, that “A serious blight is affecting a great many hemlock trees on some of our many beautifully wooded islands here in Lake Muskoka.” Pointing out that virtually all hemlocks on Stonewall Island, owned by a leading Pittsburgh businessman, had been killed, Freemantle emphasized how many Americans owned major summer homes around this part of the lake and, if they chose not to come to Muskoka because of the devastation, it would be “a serious blow” to the District’s wellbeing. He implored Finlayson to take immediate action.
In addition to prominent individual summer residents of Muskoka, the owners of lakeside resorts also pressed hard for government action. Their livelihood depended on visitors not turning away from “ugly” Muskoka as ravaged by hemlock loopers. F.J. Ames, for example, owner of Carlingford House resort, contacted Ontario forestry officials stating that “a month ago the trees were healthy and vigorous, but a blight has settled over them that is spreading with a rapidity that is astonishing.” The results are “nothing short of appalling – acres and acres of beautiful trees completely stripped and killed.” As a Muskokan with a summer hotel, he’d seen other caterpillar infestations before, “but the extensive and irreparable damage this one is causing, coupled with the rapidity of its spread, is such as to call for thorough and drastic treatment if a barren wasteland is not to be the result.” He too pressed hard for action, as did hundreds more.
Foresters Grow Alarmed About Hemlock Devastation
The fourth element building this storm was that the government – having been spurred to action by urgent appeals from individuals with political power, social standing, and economic clout – immediately investigated. “I do not know exactly what is happening to hemlock in Lake Joseph,” reported a Lands and Forests field officer ordered to the scene, adding that he’d personally seen “definite evidence” of the hemlock crisis “throughout the district.” Then Peter McEwen, Ontario’s District Forester for the area, inspected the trees himself and told Lands and Forests deputy minister E.J. Zavitz that he shared the extreme concern being expressed by people around Lake Joseph over “the worst example I have seen of damage done by this pest.” McEwen reported areas of 10 to 100 acres “in which all the hemlock has been completely defoliated.” The “worms are still very active” in areas “rapidly increasing in size,” the District Forester said. He added, I don’t “know if the trees will recover, but it is very doubtful that they will.” He told deputy minister Zavitz the infestation “appears to be spread over most of the hemlock-bearing areas of the district, to be epidemic in places, and at the rate it is spreading there is a danger of the hemlock suffering the same fate as the tamarack with the sawfly.” Meaning, the trees will be killed.
Studying the Problem But Not Acting on It
Fifth, despite provincial foresters now being duly sobered by Muskoka’s forest crisis, no action ensued.
“This Department is unable to cope with leaf-eating insects of this kind where they appear on such a large scale,” deputy minister Zavitz answered the letters pouring into his Queen’s Park office from Muskoka. He said the federal government’s forest entomologists were studying matters, and he was awaiting guidance from them.
Yet any response from Ottawa, when it came, would not be to deploy forces to fight the spreading invasion, because that exceeded federal jurisdiction over natural resources – a provincial responsibility. From its detached scientific perspective, the federal forestry staff only wanted to use Muskoka as a laboratory experiment to determine what other parasites they might, in future, introduce into such areas to prey on the hemlock lopper.
With no sign of government action at either level, desperate cottagers took matters into their own hands. “They were prepared to employ any method, even toxic remedies, to protect the beauty they so deeply valued in Muskoka,” notes Professor Kuhlberg. A number of cottagers bought forest-fire pumps and thousands of feet of hose to battle the looper. Needing information about applying poison, American businessman Fred Gratwick, whose cottaged on Lake Joseph’s Burgess Island, asked a water-pump company how to spray poison on his infested hemlocks for maximum effect. Then Gratwick sought details from the forestry entomologists in Ottawa on their recommended toxin – lead arsenate, which has been the most extensively used arsenical insecticide, for instance against the potato beetle – from proper ratios for mixing this poisonous solution to how injurious the lethal concoction might be to men spraying trees with his hoses.
A Spreading Plague Increases Urgency
A sixth factor contributing this storm was how the plague was spreading. Fall brought a cycle of change to the active season of this insect, but autumn also was accompanied by compilation of data by Ottawa’s forest entomologists that not only confirmed the severity of 1927’s looper infestation around Lake Joseph, but also a shockingly larger looper outbreak further northeast in a number of townships of Parry Sound District. The hemlock crisis was not limited by either time or distance.
“Insisting that the government take action,” states Kuhlberg, “cottagers now took the whole campaign to another level by making particularly forceful appeals. Public officials had an obligation to combat pests that attacked industry’s woodlands, they argued, but this duty was exponentially greater when the onslaughts occurred in forests that recreationalists cherished for their beauty, because such picturesque landscapes were essentially priceless.” Douglas Mason, owner of the 240-acre Chief’s Island, wrote at length to the Forest Insects Division of the Canadian government:
“The value of the Muskoka Lakes is, of course, dependent entirely upon the beauty of the wooded islands and shores, and to realise this it is only necessary to imagine the district without its timber. The timber, therefore, has a value very much greater than its actual commercial value as logs. If this were not the case, it would have no doubt been cut down before this.
“I need not go into the enormous total value of the islands and land surrounding Muskoka Lakes now used for summer resort purposes and the number of settlers and others dependent, principally or entirely, on the summer visitors. The extent of this is obvious to anyone who has any knowledge of the District and is, I think, obviously great enough to warrant consideration of the problem and effective action by the government.”
Poisoning Hemlock Loopers by Aerial Bombardment
A seventh ingredient elevating the storm was the addition of crucial new information. A stunning revelation for the well-placed businessmen coalescing into a Save Our Hemlocks crusade was that Nova Scotian experiments in chemical dusting of forests from aeroplanes had recently taken place. Lake Joseph property owners obtained internal government reports on 1927’s airborne forest protection operations in the Maritimes and immediately connected the dots. E.R.C. Clarkson, founder of the prestigious and powerful Clarkson Gordon accounting firm, whose Muskoka property lay at the head of Lake Joseph and leading the anti-looper cause, was representative of Muskoka’s high-profile summer residents now turning up full pressure on the government to unleash aerial warfare against the hemlock-destroying looper.
As it turned out, lobbying successfully for government action was the easy part.
In a second installment, we’ll see what harrowing experiences then developed with Canada’s first-ever aerial dusting of forests to save them for their beauty. The storm kept brewing. What it unleashed in Muskoka, then across Canada, was a first in forest management – and its genesis was in saving Muskoka’s hemlocks.