Mac Squires

A close friend of mine has been having a problem making sense of his place in our interconnected universe. He has recently been trying to develop a better appreciation of his place in our northern ecosystem. He and I are members of a book-study group that is studying our spiritual relationship with the cosmos, as we think we know it, using our limited abilities to understand current science and theology.
I am a retired Ontario Registered Professional Forester who has worked in and with the boreal forest for half a century. During my career I have tried to help people understand our collective responsibility to sustain that forest in as close to its evolved form as possible. Our aboriginal, and more recently our immigrant communities, have evolved in lockstep with that forest.  We are an inalienable part of it and dependent for our economic and social health on its healthy continuance.
My friend recently asked me to explain how man fits into the dynamic boreal forest within which we live. To help I took him and others from the study group on a tour of two stands along the Pennock Creek Trail near Thunder Bay, Ontario.
One stand is a rare relic that has survived to old age through a multitude of early natural disturbances. Since 1946 it has been protected from fire, insect epidemics and human extractive disturbances within a semi-urban environment. Because it was protected it now may be one of the oldest relatively intact such stands on similar soils in Northwestern Ontario. In the boreal forest only black spruce stands on waterlogged soils are likely to be older. To the informed and observant viewer the evidence of the stand’s history and its probable future is visible today.
The other stand is a rarity of the opposite extreme. It was planted by man to a precisely spaced black spruce monoculture on a formerly tilled and cropped potato farm in 1951. It is part of one of only a small number of man-made pure monocultures that I am aware of in the NW boreal forest. Those that I do know of are almost all small, only a few hectares in area, and were created for scientific study.
Here is my soap box message: In 1983, knowing the difficulty, I helped supervise an expensive attempt to create an upland black spruce monoculture using all of the tools legally available at the time on a boreal-forest clearcut. I am happy to admit that we failed. To the casual observer, that stand is today similar in species richness to many upland black spruce stands that originate after natural wildfire on similar soils. The stand is a testament to the remarkable resilience of the boreal forest. Based on 30 years of extensive walking in, and systematically observing from the ground and air, the 9,000 square kilometers of forest and hundreds of square kilometers of plantations that I managed, I now claim that extensive plantation monocultures that foresters have been criticized for are nonexistent on that land base. They almost all contain a mixture of species (10% or more other species). Indeed I believe, based on personal observations and communication with other professional foresters similarly responsible for the management of large areas, that plantation monocultures in Northwestern Ontario are largely a myth.
When I resigned from my employer in 1997 to go consulting the forest inventory of the land base that I managed showed that almost 11% of the land was covered by stands of natural origin in which 90% or more of the trees were of one species. More than one half of those stands were pure black spruce. These were NATURAL, NOT MANMADE, monocultures.
That said the following: “A Boreal Forest Tour” is an outline of the messages that I try to communicate to those who accompany me on my guided tours of the Northwestern Ontario boreal forest. I welcome comments, questions and criticisms. I am a life long learner and much of what I have learned to date has come from people with whom I initially disagreed.

A Forest Tour
by
Mac Squires, R.P.F.

1.      Driven by Fire Naturally even aged
Disturbances in the boreal forest tend to be dramatic. Insect epidemics and wind cover large areas and leave behind fuels for fires. Lightning and man have for thousands of years started fires that consume these fuels and spread beyond the original disturbance boundaries. Additionally the older a stand gets the more fuel accumulates on and near the floor and the higher the probability it will burn. Trees regenerating after a fire tend to all have approximately the same total age (the stands of trees are “even aged”). Foresters use the term “stand” to describe a group of trees that together cover reasonably similar soil and have a collection of relatively similar characteristics.

Fire tends to be a near random event
Lightning is semi random. Storms tend to follow known "lightning belts". Much of NWO has shallow soils over bedrock and some has coarse soils. Both soil types tend to dry out more during droughts therefore fuels on them are more likely to ignite and burn. Any older stands that occur are generally on deeper, finer, moister or waterlogged soils that burn less frequently, however, the frequency of fire return in Northwest Ontario is high. Therefore the area covered by "Old Growth" stands is relatively small.

Fire kills and renews
Fire kills most above ground life with degree of loss dependent on severity of fire. Bird nests and young of mammals seldom survive. Even many adults of large mammals are unable to outrun a rolling fire. Most trees, with the exceptions of large white, red and jack pines with their thick bark and high crowns, seldom survive a hot rolling fire. Almost all the above ground portions of herbs, grasses, mosses, and shrubs are consumed. Only those organisms that happen to be protected inside the stem of a large tree or fallen log or are on a small wet patch of ground are likely to survive unscathed.

Large stands
Because of the large extent of some fires stands of the same age may cover hundreds of square kilometers. Within burn boundaries there may be smaller unburnt patches that over time become "Old Growth" stands. There may be a variety of stands within the fire perimeter all of the same age but with varying species and tree density mixtures, however, some uniform “fire” stands are several hundred hectares in extent.

Species adaptation
The roots or seeds of some species survive beneath the ground surface and are among the first to appear following the fire. These would include trembling aspen and balsam poplar trees which come from root clones and white birch which sometimes sprouts from the stumps of burnt trees. Pin cherry develops from seeds spread over the years from bird and rodent droppings. Black spruce and jack pine have adapted to fire by bearing seed in fire resistant cones in the tree crowns. Even the hottest fires seldom burn the cones. Following the fire the cones soon open and spread seed. These two species together make up most of the NWO boreal forest. Large areas are covered by one or the other but usually with both in various combinations together or with aspen and birch. If the stands mature without being burnt other species such as balsam fir and white spruce slowly replace the pine and spruce. As they in turn mature wind insects and fungi often kill them before old age does setting the stage for the next fire.

2.      Science Investigating Natural Processes Insects, wind, disease, fire
Much is known from past research and collective experience about the processes that initiate insect epidemics, wind storms, disease and fire. More needs to be known. Jack pine and black spruce generally regenerate together but the pine quickly over-tops the spruce maturing first and slowly giving way to the spruce. The pine is subject to epidemics of the jack pine budworm. The spruce is relatively insect resistant and lives longer. It is shallow rooted and as it grows and reaches a critical height on mineral soils it succumbs to severe wind storms. Balsam fir, white spruce and aspen are highly susceptible to insect epidemics, disease and eventually wind breakage creating ground debris or fuel that if left alone is consumed in the inevitable fire.

Landscape patterns
Much work is being done today developing and refining computer models to assist planners in imitating disturbance patterns. These models enable planners to handle very large volumes of digital data on stand size and shape, tree, other plant, mammal, and bird species populations and habitat, soil drainage patterns and surface-water run-off among other things. Using the models it is now possible to more closely design forest management to imitate natural spatial patterns.

Succession after each disturbance and interdependence of species
More needs to be known about various succession pathways following disturbance. Each type of disturbance causes different species to initially gain dominance. Factors such as, the type and age of the stand that occupied the location prior to the disturbance, the prevailing weather before, during and after the disturbance favour a different collection of species. As time passes the initial species slowly give way to other species. The stands eventually trend toward a condition that in the absence of a new disturbance will tend to repeat (climax). Climax conditions seldom occur here, however, and some NWO foresters, including myself, have never knowingly witnessed one here.

Succession on soil and land forms
Different soil types and land forms influence which species succeed in the new forest following disturbance. Wet soils favour black spruce. Coarse dry soils favour jack pine, moist soils accommodate both along with other tree species. The tree species in turn determine mammal, bird and invertebrate species that occupy the stands. Research has determined and more is in progress determining and refining which habitats different species are dependent on and can utilize.
White spruce succeeds better on north slopes versus south slopes and balsam fir can grow practically anywhere but does best on moist deep soils where fires repeat less frequently.

Genetics, growing space
Some species such as white spruce have a wide genetic range but others like red pine have a narrow genetic range. That is to say a white spruce in White River ON is different from a white spruce north of Thunder Bay but a red pine in Newfoundland is like a red pine in Kenora, ON. Research is in progress breeding those species with the widest genetic range to tease out various genetic advantages depending on end use. More needs to be done to try to get a jump on climate change. As we select for various perceived good genes we need to be cognizant that a bad gene today may be tomorrow’s good gene. Gene conservation is therefore a critical part of any well managed tree breeding program.
A lot is known about each species' space requirements. Tree spacing has important influence over the qualities of the wood within individual trees. Generally trees that grow closer together grow more slowly in stem diameter. This has several positive effects on wood quality for lumber and pulp and paper. Past and current spacing trials are in need of repetition on different soils and more natural conditions. Black spruce grows well at narrow spacing and white spruce at wider spacing (to a point). Red pine can use a wider range of spacing than can either of the spruces. Jack pine develops very poor stem form at wider spacing and black spruce maintains a narrow crown and straight stem at any spacing.

3.      Today’s Forest is ManagedCertified as Sustainably managed
Practically all Ontario’s boreal forest south of the Albany River is managed. Most, if not all, of that forest has been certified as sustainably managed by one or more of the three main internationally recognized forest certification agencies.

Attempt to imitate natural processes and patterns
Forest management in the ON boreal forest today attempts to imitate the natural forest stand pattern and as near as practical create the conditions required by the native species.

Even aged
That pattern is a landscape covered by large areas of predominantly one age class with smaller areas of other age classes contained within the main perimeter. The overall pattern should resemble that of large, natural uncontrolled fires.

Few species
The landscape pattern of different habitats is recognized as being the dominant requirement of species that have evolved within the boreal forest. If that pattern can be sustained it is theorized that the natural species distribution and richness (biodiversity) will be sustained.

Large stands
Large stands are considered critical to the survival of many species, particularly the woodland caribou. Smaller stands tend to encourage moose, whitetail deer and hence wolves which negatively impact caribou.

Adapted species
Each species has adapted to different landscape and stand conditions. These conditions do not naturally occur simultaneously across all of the boreal forest. The different species have evolved different survival techniques to adjust to the variation of conditions. Caribou range over very large areas and move to utilize favourable conditions as they develop. Small mammals go through population cycles. These cycles are not fully understood. The population cycle of the varying hare lasts about the length of the regeneration period of black spruce and jack pine trees after fire or clearcutting but over large areas appears independent of that period. The hares begin to noticeably increase in numbers approximately five years after a fire and are sustained until there is a general large area population crash. This is food and cover related but also driven by unknown larger forces. A number of predators are in turn dependent on these small mammals for food and their cycles rise and fall with the food supply. If one were to do a population study over a short period one could conclude a disaster has occurred, however, a longer study that spans population cycles could capture the cycle and draw different conclusions. The cycles are probably evidence of species adaptation in the dynamic boreal forest and we need to understand them better if we are to manage successfully.
It appears that so long as timber harvesting patterns and frequency resemble wild fire patterns and frequency the boreal forest species will continue to respond to those patterns and frequency as they have in the past. Meanwhile foresters and biologists are monitoring responses to determine if they fit those anticipated in the plan. Additionally the forest covered by each management plan receives at least one independent forest audit every five years. The next forest management plan initiates changes based on new knowledge that has been discovered. We call this adaptive management.