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

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

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

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.