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Old Growth Forests
The following findings are extracted from a study called A New Future for Old Forests – A Strategic Review of How British Columbia Manages for Old Forests Within its Ancient Ecosystems by Al Gorley, RPF Garry Merkel, RPF Co-Chairs
A recent study tells us: “Sites with the potential to grow very large trees (Site Index >25) cover less than 3% of the province. Old forests on these sites have dwindled considerably due to intense harvest so that only 2.7% of this 3% is currently old.” We found near unanimous agreement for conserving more of these areas.
Old growth: A generic term to describe forests with old trees. In British Columbia, for management purposes, this is usually described according to the age of the trees — usually 250+ years on the coast and 140+ years in the interior.
Primary forest: Forests of native tree species, where there are no clearly visible indications of human activities and the ecological processes are not significantly disturbed.
Based on the government’s forest inventory definitions, about 23%, or 13.2 million hectares is ‘old growth’.
Not all old forest is the same, and old does not necessarily mean big trees. As much as 80% of the area of old forests consists of relatively small trees growing on lower productivity sites, such as Black Spruce bogs in the North, high elevation sub-alpine forests, or Cedar-Hemlock forests on the outer coast. Those forests remain in relatively great abundance, and are important ecologically, but they are not what many people typically envision as ‘old growth’, and although they may be disturbed by some industrial activities such as mining or oil and gas development, many are not likely to be extensively logged in the foreseeable future. Less abundant are ecosystems that are more productive from a timber perspective and have not already been heavily logged.
Of the 13.2 million hectares of old forest, 33% (4.4 million ha) is protected and 67% (8.8million ha) is not. Protected means the old forest is in parks, ecological reserves, ungulate winter range no-harvest areas, private conservation lands, regional water supply, wildlife management areas, OGMAs (legal and non-legal) and retention VQOs. Of the old forest that is not protected, 38% is within the THLB, while 62% is not as it is assumed to be currently inoperable.
Forests with old and ancient trees contain unique combinations of attributes that grow from ecosystems that have formed over centuries or millennia. These attributes can rarely, if ever, be replicated in younger or compromised ecosystems, even if they contain old trees. It is also important to understand that the age and characteristics of old forests vary greatly between ecosystem types and therefore their descriptions and values are relative. In other words, a forest on the coast may have several species and many ages of trees, whereas drier Interior forests may have only one or two species and be relatively evenly aged. Of course, forest values go far beyond just the trees, as forests also contain other plants, insects and animals, many of which require old forest to survive.
Some of the many values found in forests with old and ancient trees are:
- Unique conditions and processes that are important to conservation of biodiversity;
- Unique species, many of which are still undiscovered;
- Banks of genetic material for future use or adaptation strategies;
- High value timber with qualities not found in younger forests;
- Resistance to fire;
- Interception and storage of water;
- High carbon storage and sequestration capacity;
- Botanical forest products, including medicinal, edible, decorative, and ceremonial plants;
- Fish and wildlife habitats, including essential attributes for nesting or denning, thermal protection and hiding from predators;
- Spiritual and cultural uses, including carvings, canoes, and ceremonial poles;
- Aesthetics such as resident viewing and tourism;
- Commercial and non-commercial recreation; and
- Knowing they are there for their own sake — intrinsic value.
Many people identified specific highly diverse and complex ecosystems that support very large, old trees, and have persisted in a relatively stable climax condition for centuries. These “ancient forests” are globally unique, rare, and contain species as yet undiscovered, and many of these ecosystems and old forests are simply non-renewable within any reasonable time frame . They promote protecting these areas from human disturbance to conserve a wide range of benefits, and particularly for their intrinsic value.
Consistent with what we heard from several provincial government staff, a recent report submitted to the panel by a group of independent scientists illustrates that we are in situations of high risk to biodiversity in many areas in the province, particularly in high-productivity, low elevation ecosystems. More troubling is the future projection where almost all of the province will be in high biodiversity risk once our current management approach harvests most of the available old forest. The time to complete this transition depends on the available old forest and various industry and economic factors in each region. Their research also provided the list of BEC zones that contain less than 10% of their original old forests.
Old Growth Management Area Concerns
- Poor or unjustifiable location (e.g., doesn’t contain old trees, fire hazard)
- Too small
- Not flexible enough to accommodate forest dynamics
- Flexibility abused for roads or development
- (Plus 7 other concerns)
Climate change will become an increasingly bigger factor in choices about forest management.
The priorities that currently drive our forest management system are backwards.
The following findings are extracted from a study called BC’s Old Growth Forest: A Last Stand for Biodiversity April 2020 Karen Price, Ph.D., Rachel F. Holt, Ph.D., R.P.Bio and Dave Daust R.P.F., M.Sc.
Our analysis concludes the following:
- The provincial total area of old forest (~13.2 million hectares) matches our total.
- The vast majority of this forest (80%) consists of small trees:
- ~5.3 million hectares have site index2 5 – 10m; another ~5.3 million hectares have a site index 10 – 15m.
- Small trees characterize many of BC’s natural old forest types, including black spruce bog forests in the northeast, subalpine forests at high elevation, and low productivity western redcedar forests on the outer coast.
- Large areas of this old forest type remain because the trees are too small to be worth harvesting (at today’s prices).
- In contrast, only a tiny proportion of BC’s remaining old forest (3%) supports large trees: ~380,000 hectares have a Site Index 20 – 25m, and only ~35,000 hectares of old forest have a Site Index greater than 25m.
- These types of forests match most people’s vision of old growth. They provide unique habitats, structures, and spiritual values associated with large trees.
- Productive old forests are naturally rare in BC. Sites with the potential to grow very large trees cover less than 3% of the province. Old forests on these sites have dwindled considerably due to intense harvest so that only 2.7% of this 3% is currently old (see pie chart pg 7). These ecosystems are effectively the white rhino of old growth forests. They are almost extinguished and will not recover from logging.
- Over 85% of productive forest sites have less than 30% of the amount of old expected naturally, and nearly half of these ecosystems have less than 1% of the old forest expected naturally. This current status puts biodiversity, ecological integrity and resilience at high risk today.
The forest industry presents a different perspective.
Backgrounder: Status of BC’s Old Forests 2021
It appears that the statistics provided by industry includes large areas of Black Spruce bogs and sub alpine forests, etc. not only the remaining 2.7% of the less than 3% of the old forests that are of concern.
