Forest Health

Forest Health: Eating Themselves Out of House and Home: Mountain Pine Beetle Attack Spruce!
Forest Health Focus on Safety, Association Reports The current outbreak of mountain pine beetle (MPB) in BC, and now Alberta, has attracted immense media attention as it has rolled through more than nine million hectares of mature lodgepole and ponderosa pine. Mountain pine beetles breed in almost all pines, raising concern that the insect may expand into the jack pine of the boreal forest that stretches across Canada to the Maritimes. Behind the eastern front, most of the insect’s typical food supplies have been exhausted. For example, in many parts of the central interior of BC, the insect, facing starvation, is increasingly attacking young lodgepole pine and, to a much lesser degree, mature spruce.
For mountain pine beetles to successfully reproduce in trees, two things must occur. First, there must be enough insects to successfully overwhelm the tree’s defensive capacities. Mountain pine beetles use chemicals known as pheromones to attract their mates to trees en masse. This mass attack, in concert with fungi vectored by the beetles, is able to kill mature trees in outbreak conditions. Second, the subcortical tissue of the trees, once gained, must be suitable for brood to develop. For example, while stands of small-diameter juvenile lodgepole pine killed by mountain pine beetle may pose serious challenges for the future timber supply, attacking such trees is actually a dead end for the beetle as a reproductive strategy. In young pine with diameters less than approximately 17 cm, the phloem, which the insects eat, is simply too thin for larvae to mature to adults.

Over the past two years we have noted a number of successful colonizations of mature interior hybrid spruce by MPB. In truth, attacks by MPB on spruce have been documented several times in the past one hundred years, stretching back to records from the father of forest entomology, A.D. Hopkins, in 1921. Such attacks often occur when the insects are abundant, such as during outbreak conditions. As a rule, however, the attacks are not very successful. Spruce trees are rarely killed, and even if the trees are colonized, the broods rarely develop to adults. Thus, we have been surprised to find that brood production in spruce, at least in the wake of the current outbreak, may be sufficient in some instances to result in a new generation of beetles emerging to attack new trees!
We are conducting research to address four potential hypotheses for why MPB are reproducing in the occasional spruce. First, this so-called epiphenomenon may be simply due to the unprecedented population pressure given the magnitude of the current outbreak. Second, we may be witnessing an exceedingly rare, but not impossible, host switch. Species of bark beetles in the genus dendroctonus exhibit many different host preferences. Some attack all pines, others only one, while others attack only spruce or Douglas-fir, or larches. A likely step in the speciation of tree-killing bark beetles that specialize on certain hosts is the formation of “host races” or strains that become reproductively isolated in different tree species. Third, differences in the population genetics or characteristics of MPB between locations may be facilitating the phenomenon. Perhaps there are always a few insects that are able to colonize spruce, but it has taken until the current outbreak to concentrate sufficient numbers in one location. Finally, the phenomenon simply may be due to site-specific characteristics of these individual spruce trees, and not the insects at all. There may be something unique about the trees’ vigour, physiology, and beetle susceptibility that have made them desired candidates versus other nearby spruce.
We are currently studying colonization behaviour, reproduction potential, and fungal transmission by MPB in spruce using a combination of laboratory and field experiments. Our research, based at the University of Northern British Columbia (UNBC), is aided by graduate and undergraduate students at the institution and collaborators at the Canadian Forest Service Pacific Forestry Centre in Victoria, the BC Ministry of Forests, and UBC. To date we have drawn only one conclusion after reading Hopkins and others’ initial notes in this subject area: the bugs never read the scientific literature!

Brian Aukema (baukema@nrcan.gc.ca) is a research scientist in forest entomology with the Canadian Forest Service, Natural Resources Canada, based at UNBC as an assistant adjunct professor in the Ecosystem Science and Management program. Robert Hodgkinson (Robert.Hodgkinson@gov.bc.ca) is forest entomologist for the Northern Interior Forest Region for the BC Ministry of Forests and Range in Prince George. Dezene Huber (huber@unbc.ca) is an assistant professor and the Canada Research Chair in Forest Entomology and Chemical Ecology at UNBC. Staffan Lindgren (lindgren@unbc.ca) is a professor of forest entomology in the Ecosystem Science and Management Program at UNBC.

Climate Change

Tree Improvement in a Changing Climate
by Brian T. Barber, MA, RPF Tree improvement, which is the selection, breeding, testing, and production of trees with desirable traits, has a long and successful history in BC. Selection of coastal Douglas fir “plus trees” and superior provenance testing began in the 1960s. Today, there are breeding programs for ten commercial tree species that focus on improving growth, form, wood quality, and pest resistance. The best performing parents in these programs are established in 99 orchards that produce seed for specific seed planning zones and elevation ranges. 40% of these orchards are managed by the private sector, 30% by the BC Forest Service (BCFS), and the remainder through cooperative arrangements. In 2007, 44% of the 273 million trees sown in BC were derived from orchard seed and 6% were from identified superior provenances. This select seed had an average genetic worth of 14%, which represents the expected timber volume increase at rotation as compared with using untested wild seed. Select seed use is projected to increase to 75% of total provincial seed use by 2013, and the average genetic worth (measured in timber value) is forecast to reach 20% by 2020. The expected benefits of using select seed include an increased long-term timber supply and improved forest health. Since trees planted on Crown land become the property of government, there are few incentives for licensees to invest in long-term tree improvement activities. As a consequence, breeding is conducted by geneticists working for the BCFS and select seed with a genetic worth of 5% or greater, if available, must be used when planting trees to establish a free growing stand. However, there are also shorter-term benefits to using select seed, including reduced time to achieve free growing and relief from harvest adjacency constraints (e.g. visual and hydrological green-up), reduced brushing and weeding costs, and improved nursery recoveries. 

Tree improvement, and other forest genetic resource management (GRM) activities, are coordinated by the Forest Genetics Council of BC (FGC), a multi-stakeholder body appointed by BC’s Chief Forester. The FGC advises the Chief Forester on policy matters, establishes goals and priorities, and allocates public funds from the BC Forest Investment Account to GRM activities.

Climate change was the primary driver identified by members of the GRM community of practice and stakeholders in a recently completed program review undertaken by the FGC. Climate change is also the impetus behind the Chief Forester’s Future Forest Ecosystem Initiative (FFEI). Public expectations for developing responses to climate change are increasing and governments are setting aggressive targets for reducing greenhouse gas emissions. The FGC and BCFS are now grappling with the challenge of incorporating climate change and carbon management into their goals, programs, and operations. GRM activities will play an important role in mitigating some of the potential impacts of climate change on BC’s forests.

In a rapidly warming climate, trees will eventually become maladapted to their environment resulting in reduced productivity and increased susceptibility to extreme weather events (e.g. storms & drought), fire, insects, and disease. Tree populations will have to adapt to these new conditions (through phenotypic plasticity or natural selection), migrate to more suitable areas, or perish. The rate of climate change expected to occur over the next century, however, exceeds the adaptive capacity of most long-lived tree species. As a consequence, one of the few proactive forest management responses to address climate change is to assist or facilitate the migration of species and seed sources through planting.
Researchers at UBC’s Centre for Forest Conservation Genetics, BCFS, and other institutions are developing climate models and tools to assist resource managers in developing adaptive strategies. One of these models produced the “flying biogeoclimatic zones” developed by Hamann and Wang (2006), which were featured in Richard Hebda’s November 2006 article in Canadian Silviculture magazine. Researchers are also using these models, vegetation inventory data, and information from provenance and progeny field tests to project changes in tree species ranges and to identify strategies to reduce losses and increase forest productivity under different climate scenarios (excluding losses due to fires, pests, and weather events, which are expected to increase in frequency).

Although there is some uncertainty about the rate and magnitude of warming and changes in precipitation patterns, especially at regional and landscape levels, these trends are becoming evident and can be improved upon over time. Further development of climate models, combined with applied knowledge of local geography, plant physiology and forest genetics, will assist foresters in selecting species and seed sources more resilient to a changing climate.

Carbon Standard

• Turning Pulp Mills into Biorefineries
• NA Forest Carbon Standard
• Should Marginal Farmlands be Used for Forests or Food?

Biodiversity Conservation

biodiversity conservation magazine, Biological diversity, or biodiversity, is a term that is becoming more and more heard, yet few people really know what it is. There are many definitions for it (see the first chapter of Gaston (1996) for a long list), but there are two that will be given here. The first is from the Convention on Biological Diversity, also known as the Rio Summit: "'Biological diversity' means the variability among living organisms from all sources including, inter alia, terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are part; this includes diversity within species, between species and of ecosystems." The Canadian Biodiversity Strategy defines it as "…the variety of species and ecosystems on Earth and the ecological processes of which they are a part". It is often simply used as a catch-all term for nature. No definition is perfect; as with life itself, it's a bit nebulous and there are always exceptions.
How do changes to the environment affect the many species of plants and animals on the planet? Learn about the environmental issues that affect biodiversity, and about conservation efforts that can maintain biodiversity around the world.

Forest Magazine

Silviculture Magazine
Forests are being valued as a source of biomass for energy, and as a way of sequestering and storing atmospheric carbon, but is the harvest of forest biomass for bioenergy sustainable?

Silviculture Magazine

Canadian Silviculture magazine reports on the latest trends and current issues in the silviculture industry such as bio-energy, carbon credits, ecosystem restoration and fuel management in the forests. Canadian Silviculture has respected, industry professionals that exclusively cover all aspects of silviculture including site preparation, tree planting, fertilizing, pruning, spacing, and commercial thinning. It is the only magazine in Canada dedicated to silviculture and the enhancement of our forests and is an excellent source of information for industry leaders.
Silvicultuer Magazine

Forest nursery

Forest Nursery Production in BC - the Formative Years Recognition of the need for research into the growing and planting of coniferous species precipitated the establishment of a small government research nursery in Victoria, BC in 1926. That test nursery was closed in 1932. The first production nursery was opened at Green Timbers in Surrey, BC in 1930. Another coastal nursery was established at Quinsam near Campbell River in 1939. The production from this nursery provided planting jobs for many men who had become unemployed during the depression, and served to re-establish the Sayward and Campbell River forests that had been decimated by wildfires during the late thirties. Production at the Quinsam nursery was later relocated to its present site at Gordon Road just west of Campbell River. Additional coastal nurseries were established at Chilliwack, Duncan (Koksilah), and Surrey, BC.

Reforestation

Editorial: Reforest What you Reap
The area reforested includes planting and natural regeneration and is net of reforestation failures. Harvesting is by any method and includes for any purpose. Losses to fire and pest are only the unsalvageable as the salvageable will be reforested under law. The ratio of area harvested to area reforested by the timber industry, as reported by the Forest Practices Board province wide audit in 2002, is a great success being in balance or a perfect 1. The BCMOF did not report on the harvest by oil and gas industry for the temporary use of seismic lines and well sites. This industrial use without reforestation needs to be redressed to restore sustainability in the harvest/reforestation balance.

Biodiversity Silviculture Magazine Forest health