New Zealand Journal of Forestry (1973) 18(2): 217–232
©New Zealand Institute of Forestry
Provenances of Pinus radiata: their early performance and silviculture potential
R.D. Burdon and M.H. Bannister
The five natural populations of Pinus radiata (from Ano Nuevo, Monterey, and Cambria in mainland California, and from Guadalupe and Cedros Islands) were planted with two local ones (from Kaingaroa and Nelson) on two contrasting sites in Kaingaroa Forest during 1964-67.
Kaingaroa and Nelson maintained a 5 to 10% height advantage. This probably reflects adaptation by selection under local conditions, together with the free outbreeding which prevails in plantations. Guadalupe averaged about 9 to 15% shorter than the mainland populations, although some individuals were very vigorous. Cedros was much slower growing.
Among mainland populations, Cambria appears more exacting in site requirements than the others and was more susceptible to Dothistroma blight and leader die-back. Both island populations are especially prone to boron deficiency. Cedros is more frost tender than the other populations, while Guadalupe and Cambria are particularly susceptible to die-back. Among populations, resistance to Diplodia die-back is apparently related to oleoresin composition in the same way as among individuals within local stock.
Morphological differences largely reflected differences in persistence of juvenile characteristics, which was greatest in Cambria and least in Guadalupe. Cambria is distinguished by fewer branch clusters but all populations vary strikingly in this respect. Tree form appears worst in Ano Nuevo, but it responds readily to selection-Wood density in the first five growth rings was highest in Guadalupe. In Cambria, it was slightly lower than in the other mainland populations.
The Kaingaroa and Nelson populations appear to have originated mainly from Ano Nuevo, where seed collection was probably easiest.
Future breeding will depend primarily on local stock, but some parents from natural populations could provide certain desired characteristics and broaden the genetic base.