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WVPPCA members who visited the Valley Pine orchard during last summer's tour were impressed by the orchard's vigorous growth. Many of the one-year-old container seedlings planted in 1996 had already grown to more than seven feet! All without irrigation or fertilizer… just weed control, deep, silty loam soil, and our fine Willamette Valley climate.
The Association's goal is to select at least 160 naturally occurring parent trees -- enough to conserve the genetic resource of Valley Pine -- and plant their progeny at the seed orchard site. The orchard will serve as a gene bank and will also produce seed cones so that landowners can re-establish this species in the Willamette Valley.
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The orchard's first phase was planted in 1996 with seedlings representing 40 parent trees. Eventually, a total of 160 parents were selected and it was hoped that their progeny could all be planted by 1999. A second phase was planted last spring with seedlings from 72 parents, bringing the orchard up to its planned size of 15 acres. The remaining 48 parents did not yield enough cones to grow seedlings, so a plan was devised to graft their scions into the orchard. Using trees within the phase I area as rootstock, the grafting project proceeded under a contract last May. These efforts were not entirely successful, so work will continue next spring. "Soft tissue" grafting in ponderosa pine is challenging; it must be done with fresh cuttings while both the donor and the rootstock shoots are actively elongating.
When completed, the 15-acre orchard will consist of half-sib (wind-pollinated) progeny as well as the clonal grafts. Seed production will be enhanced through cone stimulation techniques, and the cones themselves will be pollinated by the orchard's wind-dispersed pollen cloud. Although a major goal is to preserve genetic diversity, there are possibilities for enhancing the growth potential of orchard seed by selecting promising trees. The Association will sort out these ideas; meanwhile the orchard staff has begun to practice applying cone stimulation techniques on the young ponderosa pines.
