The trumpet sounds

Natural Disasters – Part 2

OPINION

A great mountain burned with fire, and a third of all trees and grass burnt-up. – Revelation Ch.8

The Madawaska Valley’s winter of 2023-24 has been the driest in recorded history. Renfrew County, situated within the rain shadow of the Algonquin Dome, receives considerably less annual precipitation than Haliburton and other jurisdictions to the west. Our snowpack made a hasty retreat this spring and creeks which normally run into June are already dry. Drought seems inevitable and with it come wildfires. Fires are the second most frequent natural disaster after flooding in Canada. Each year 1,200 wildfires, consuming an average of 200,000 ha burn in Ontario. Above: Water bomber drops water taken from nearby Ottawa River to douse flames on Eardly Escarpment. All photos C.Huggett

How have we inadvertently made this inevitable reality worse. Are we prepared?

Low intensity wildfires were historically permitted to burn themselves out. But industry and human settlement into hinterland regions in the past two centuries made this practice unfeasible. Hence, although the Ottawa Valley’s mature forests were mostly harvested by the 1980s, the cyclical nature of commercial logging with rotation periods as little as 20 years, means fresh wood waste from slash is always somewhere on the landscape usually within a 3 km radius to human activity or habitation.

For my days are consumed like smoke, and my bones are burnt as a hearth. – Psalm 102

Any woodsman knows that tossing a green poplar log onto a camp fire is the equivalent of pouring mud onto smouldering ashes. It does not burn. Birch trees rot from the inside out. The punky moist interior wood simply will not burn. When they die, sections of the trunk’s interior absorb so much water that the dead tree drops off in columns. The adage “Rotten wood cannot be carved” not only applies to those lacking tenacity and motivation, but also to the rotten detritus and logs littering an undisturbed forest floor.

In short, most decaying wood is fire resistant. Natural forest litter that decays rapidly does not present a fire hazard nor do many fire resistant living tree species. What does burn, however, is recently cut conifer slash, especially within the first one to ten years. Fires are essentially chemical reactions involving heat, oxygen and fuel. The objective is to remove at least one of the variables and then the threat is “extinguished.” The problem emerges when forestry operations clear large cut-blocks of the forested landscape within close temporal proximity to one another. The “downed woody debris” from delimbing, abandoned defective trunks and tops accumulates on site — material which normally takes at least five years to begin to decompose. During this “high risk” period, conifer slash left in windrows and debris piles acts as kindling to wildfire. In the 1980s Eastern Ontario best forestry practices encouraged companies to “reduce the vertical profile” of abandoned wood-waste.

Currently, skidders bulldoze the unwanted materials into huge piles, which lengthens the time for the stacked anaerobic organic material to breakdown. Add to this the region’s mysterious balsam fir die-back (a resinous conifer which normally decomposes quickly, but is vulnerable to spontaneous combustion) … and we have a disaster in the making. In short, traditional chopping, thinning and clearing forest is not the solution as it raises the ambient temperature, dries residual waste, and elevates wind velocity. The highest risk areas are recently harvested conifer stands. The lowest risk areas are undisturbed hardwood stands surrounded by wetlands which act as firebreaks.

The main variable that induces wildfires is simply the lack of moisture. Thus, the primary objective to reducing the fire risk is to retain moisture within the landscape. Shade retention by safeguarding a dense, closed, upper canopy not only reduces the ground’s ambient temperature from direct sunlight, it prevents the evaporation of critical moisture. Here, conventional thinking is at odds. Thinning a woodlot increases air circulation causing a rapid loss of moisture into the atmosphere, dries out forest biomass making it vulnerable to ignition while retarding important decomposition from microorganisms. The increased oxygenated air circulation acts like a bellows within a blast furnace. The result: an uncontrolled wildfire.

Rural homeowners have the uncanny preoccupation to clear trees and encourage grass, (probably in a subconscious compulsion to live up to their neighbours; i.e. the Urban Jones). Grass ignites quickly and spreads to surrounding forest which under drought conditions can spark canopy fires, creating their own microclimate and an inferno second only to biblical prophecy. Now instead of a quick carpet rush of flame, we have a burn that annihilates every living organic/ inorganic organism right down to the inert surficial bedrock. It takes centuries to heal — if at all. Districts along Highway 7 like Kaladar are prime examples where organic soils were burnt off from cyclical intense fires and only scrub trees managed to return.

Apart from the proverbial cigarette butt, what human triggers ignite our woodlands?

The exhaust system of pickup trucks and off-road vehicles such as ATVs, dirt bikes, lawnmowers, inappropriately stored
combustible gasoline or linseed oil/rages, chainsaws and industrial machinery. Grow-op generators have been known to cause forest fires. Domestic cars driving over grass can ignite fires from their exhaust pipes. Even broken glass has magnified sunlight to burn parched ground.

Long before the orange glow is seen over the horizon, the pungent smell of woodsmoke becomes apparent, which increasingly smells more like melting micro-plastics rather than burning wood. The rain of ash quickly follows. Like the gases of an erupting volcano the smoke can almost be as deadly as the heat and flames. Drought brings other concerns: dieback of healthy trees, a drop in the water table with associated dry wells, and a poor hay crop for local farmers. As beaver ponds dry up, cavity nesting birds, herons and waterfowl abandon nests now accessible to predation from racoons and other predators. This is when escaping to the rooftop, loading up the truck or submerging yourself in a local lake becomes futile.

So, how are our government and municipalities stacking up in emergency preparedness? Apparently not very well. Not according to a recent resolution distributed from Limerick Township to surrounding jurisdictions.

Municipalities are preoccupied with the questionable federal and provincial forest fire response capability which primarily rely on water-bombers which skim and scoop surface water to dump on hot spots in the forest. There are rumblings that an ageing fleet of water bombers not only needs replacing but the number is sorely inadequate for the task and projected 15 percent fire risk ncrease predicted by 2040. (I predict that the stats are outdated and the wildfire risk will be substantially higher.)

Unless we integrate forest fire mitigation practices by increasing the rotation period of harvesting, spacing cut-blocks, retaining an adequate closed canopy after cutting and reducing the vertical profile of abandoned slash, commercial forestry will risk seeing its forest inventory ($) go up in smoke.

On the domestic front, property owners should encourage a shade intensive, damp dense woodlot to avoid air circulating and drying out the forest thus removing the matrix for fire, oxygen, direct light/heat, and moisture loss. Converting forest into lawns should be discouraged and existing lawns kept short. The old adage that “Nature Knows Best”, (selectively bred out of the human psyche for generations) must be relearned, embraced and enthusiastically adopted. The fragility of the living condition should never be submerged by human arrogance assuming somehow our technology will uncover the ultimate answer.

Common sense is not always so common.