Coastal Douglas-fir tree breeding program
In general, the primary goal for coastal Douglas-fir breeding is to improve volume production at rotation while maintaining wood density at the population level. This breeding program currently uses recurrent selection; however, genomic selection approaches, especially for more mature traits, are being explored as is screening for Swiss needle cast, a needle fungal disease, that is expected to become more prevalent with climate change.
Tree improvement and breeding efforts in coastal Douglas-fir are restricted to three seed production units.
Seed Production Units (SPU)
SPU 1 ranges from 0 to 900 metres elevation in coastal areas west of the Coast Mountains. It is the most important coastal Douglas-fir SPU. In this area, roughly 10 million trees are planted annually with seed produced in orchards. In SPU 1, seed orchards are now at third-generation selections, with anticipated genetic gains of 25 to 30 percent (volume gain at rotation of age 60).
SPU 19 is smaller than SPU 1. It is in the coastal-interior transition (sub-maritime) zone at an elevation band between 400 and 1100 metres. Seed use in this zone is roughly 1 million seedlings per year.
SPU 31 is a minor component in coastal high-elevations between 900 and 1200 metres. Only 0.5 million seedlings are planted per year.
The genetic gains in SPUs 19 and 31 are more moderate than in SPU 1 (7 to 15 percent), and come from backward selections based on progeny testing.
- Kranabetter, J.M., Stoehr, M., and O'Neill, G.A. 2015. Ectomycorrhizal fungal maladaptation and growth reductions associated with assisted migration of Douglas-fir. New Phytologist.
- O’Neill, G.A., Stoehr, M., and Jaquish, B. 2014. Quantifying safe seed transfer distance and impacts of tree breeding on adaptation. For. Ecol. Manage. 328: 122-130.
- Stoehr, M., Ott, P., and Woods, J. 2014. Inbreeding in mid-rotation coastal Douglas-fir: implications for breeding. Ann. For. Sci. 72(2):195-204.
- Adams, R.P., and Stoehr, M.U. 2013. Multivariate detection of hybridization using conifer terpenes II. Analysis of terpene inheritance patterns in Pseudotsuga menziesii F1 hybrids. Phytologia 95(1): 42-57.
- Stoehr, M., J. Woods, and A. Yanchuk. 2011. Selection Approaches in High-Elevation Coastal Douglas-fir in the Presence of GxE Interactions. Silvae Genetica 60(2): 79-84.