The applied breeding programme of Sitka spruce passed over to the Conifer Breeding Cooperative (CBC) in 2013. Prior to the formation of the CBC a complete re-analysis of all the original plus trees was carried out by an independent body using all the available progeny data collected to date including half-sibling and full-sibling field trials. This resulted in new Breeding Values for the economic traits under selection; diameter, wood density and stem straightness. These data in turn have resulted in a re-estimation of the predicted genetic gains in the various Sitka spruce seed orchards in Britain.
Parents of families
These are special seed lots (or in some cases plants) which have been supplied to the GB Forestry Commission (FC) and private nurseries since 1981. They have been used for commercial vegetative propagation and also for purely research applications.
They are either half-sibling (polycross) or full-sibling (specific cross) mixtures of seed from parents of proven superiority over direct import Queen Charlotte Islands, British Columbia, Canada (QCI) material for growth and quality traits. The seed has been produced using controlled pollination techniques between highly selected parents. Since 2013 such controlled pollinations have been carried out exclusively by the Conifer Breeding Cooperative.
The new predicted genetic gain figures for Sitka spruce seed orchards, and parents of families owned, or produced by Full-Members of the CBC can be seen by following this link:
For all other orchards please contact the relevant owner. Details of seed orchard location and ownership are available in 'The National Register of Basic Material' which can be viewed in the Forest Reproductive Materials section of the Forestry Commission website: www.forestry.gov.uk/frm