Revised predicted gains for Sitka spruce

Revised predicted gain figures for tested clonal Sitka spruce seed orchards.

All figures are percentage (%) gain relative to unimproved material imported from the Queen Charlotte Island (QCI).

Note the orchards listed are those under the control of Full Members within the Conifer Breeding Co-operative.

For predicted gains of seed orchards belonging to other organisations , please contact the relevant seed orchard owner.

A complete list of UK seed orchards, their location and ownership is available by visiting ‘The National Register of Basic Material’ available on the Forest Reproductive Materials section of the Forestry Commission website: www.forestry.gov.uk/frm

Disclaimer: 

The predicted gain figures presented above assume:

1. No contamination from rogue pollen originating from outside the seed orchard;
2. An equal contribution of male and female flowers from all the constituent tested clones (a situation know as ‘panmixis).
3. All seed orchards were originally planted on sites suitably isolated from stands of the same or hybridizing species but this may have changed with time. Also in practice panmixis is rarely likely to happen although in good flowering years when most of the clones appear to be flowering, it is unlikely that there will be significant deviation from the predicted gain figures. In years of poor flowering when only a few clones are dominating the production of male and female flowers, there could be considerable deviation from the predicted gain figures. Ask the seed orchard owner about deviation from panmixis and updates of gain predictions.
4. The Conifer Breeding Co-operative does not own any seed orchards in its own right, and bears no responsibility for deviations from predicted gain figures as a result of contamination by rogue pollen or seed collections during years when clones are not approaching panmixis. It is the responsibility of the purchaser of these seed or trees raised from these seed to make enquiries of the vendor or seed orchard owner regarding possible rogue pollen sources and the flowering rate during the year of collection.