Yellow cypress tree breeding program

Yellow cypress (Callitropsis nootkatensis) is a member of the cypress family and has naturally durable heartwood.

Advanced generation breeding has been put on hold. As clones from the clonal program age and no new clones are being tested, interest has shifted to siting orchards in manageable natural environments conducive to flowering. Successful cone crops with viable seed have been produced at operational levels in low elevation coastal fog belt ecosystems such as:

• Port McNeill
• North Vancouver Island
• Jordan River, South Vancouver Island

Currently, improved orchards are being planned on these sites using clones selected from the breeding program and from Western Forest Products trials. Genetic Worths of 15 to 20 percent volume are projected to be similar to clonal production due to low non-additive genetic variances.

History

Initial wildstand parent tree selections were made for the Maritime (0 to 1000 metres) seed planning unit (SPU) in the 1970/1980s and were established in seed orchards with no breeding program planned. These “off-site” orchards did not produce seed and were abandoned.

A clonal program was initiated in the late 1980s with approximately 5000 clones established in field trials. The clones were propagated using juvenile seedlings from first-generation matings (300 parent trees using eight-tree partial disconnected diallels). Selections have been made from these clonal trials at age 12 based on growth and tree form, and are currently used as donor stock for cuttings for reforestation. Genetic worths of 15 to 20 percent volume are projected to be similar to clonal production due to low non-additive genetic variances. Genetic worth of these veglots is more than 20 percent volume at 60 years of age.