Project Summary

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Introduction:

Added-value and diversification in wood products is becoming the paradigm in our forest management. Among native hardwood species, red alder has the most potential for high-value products, e.g. furniture and other specialty products, and black cottonwood is the only native species conducive to intensive short-rotation (less than 10 years) silviculture for fibre production through clonal forestry of either pure species or hybrids.

Adaptive patterns of geographic variation within the species' natural range is the basic biological information for effective silvicultural prescriptions and attainment of forest management goals. Given the increasing public concern over maintaining biodiversity in our forests, "minor species" will become increasingly important in our silvicultural practice. It is time to direct some of our research efforts to our native hardwood species.

Little is known about genetic variation in red alder and cottonwood in British Columbia. The establishment of patterns of geographic variation and genetic architecture in seedling/steckling growth, biomass production, vegetative phenology, and possibly molecular gene markers and nitrogen fixation (red alder), and the relating of observed variation patterns to physiographic and biogeoclimatic variables will have practical implications for hardwood silvicultural management including the potential of selecting productive red alder seed sources and sources of high nitrogen fixation capability, the assessment of the effect of future climate change on adaptability of native hardwood species, and efficiency in management of gene resources and biodiversity.

Objectives:

• To establish stool beds (cottonwood clones) for vegetative propagation of rooted cuttings.
• To prescribe preliminary guidelines for operational collection of red alder seeds and cottonwood clonal materials, based on literature review and natural variability observed during the sampling of testing materials.
• To determine the magnitude of genetic components associated with seed sources vs. among trees within sources in those seedling and steckling traits.
• To construct regression models relating seed source variation in sampling and steckling traits to physiographic and biogeoclimatic variables.
• To map genetic variation patterns, based on the regression models constructed, as a basis to guide seed transfer and selection of seed sources.
• To evaluate the stability over ages in genetic patterns observed above.
• To assess seed source differences in growth, stem quality, pest tolerance and other economic and adaptive traits.

Seed and Cutting Collection:

1. Sampling scheme
   
   a) Red alder seeds were collected from about 70 stands in six geographic areas, Q.C.I., Skeena R., Vancouver I., Knight Inlet or Bella Coola, and Howe Sound/Squamish R. In each area, attempts were made to sample all biogeoclimatic variants where red alder grows naturally.
              
   The choice of the three main river drainages (Skeena, Knight, and Squamish) was mainly for the consideration of accessibility.
   
   b) Black cottonwood cuttings were sampled systematically from 10 to 15 stands (five trees each stand) along the following drainages; Lower Fraser River, Vancouver Island, Squamish/Harrison River, Bute/Toba Inlet, Knight Inlet, Rivers Inlet, Bella Coola/Dean River, Nass/Skeena River, and Stikine River; additional 10 to 15 stands from along Nechako and Fraser Rivers to forma a coast-interior loop that links the migration corridor between coastal and interior populations.
   
   Seeds from two or three stands (20 to 25 trees each stand) at Skeena/Nass or Lower Fraser River were collected for estimation of genetic variability within families and studying of mating systems.
   
2. Selection of Stands and Seed/Cutting Collection
   
   a) Red alder stands chosen for collection were "typical" natural stands of red alder: 20 years or older, reasonably large in  size (4 hectares), not of recent colonization along logging roads, on landings or recent clearcut areas, or on wet sites.
   
   Approximately one litre of cones were collected from each of five trees at each stand, trees spaced by about 50 m. Seeds from individual trees were kept separate.
   
   b) Black Cottonwood stands were sampled near the river mouth and also at the extreme river upstream where natural cottonwood grows, to ensure the sampling of natural stands along the whole environmental gradient of each river drainage; stands in between about 30 K apart. Stands with cottonwood as the dominant component species were preferred. Trees younger than 20 years were chosen for cutting collection to ensure high rootability whenever possible. Cutting collection was limited to one-year-old leaders.

Studies:

1. Short-term common garden testing

References and Publications (Click on Highlighted References to Obtain an Electronic Copy in PDF Form):

Ying, C., Courtin, P., Xie, C.Y., Carlson, M., and Coopersmith, D. _____. Adaptive Variation and Genetic Architecture in Red Alder (Alnus rubra), Black Cottonwood (Populus trichocarpa) and Balsam Poplar (Populus balsamifera) Populations. Working Plan, Sustainable Environment Fund Forest Renewal Initiative Program Hardwood Management Research Proposal B04. B.C. Ministry of Forests, Research Branch, Victoria.

Ying, C., and P. Courtin. 1991. Geographic variation of red alder (Alnus rubra) in British Columbia. E.P. 1121.01 Working Plan. B.C. Ministry of Forests, Research Branch, Victoria.

To obtain any publications that are not highlighted click here.

Acknowledgments:

Support for this project has been provided by the B.C. Ministry of Forests, the Canada-British Columbia Partnership Agreement on Forest Resource Development (FRDAII), and Forest Renewal BC.

Last Updated: May 28, 1998.