In a joint effort with Oregon State University cooperative extension, the Oregon Chapter has identified promising individual trees as sources of seed for new plantations. Several test plots have been established since the local chapter was founded three years ago. In order to select the best seed sources for new plantations, there is an on-going need for more nut collections from good local trees, establishment of seedling seed orchards, and progeny trials. The strategy which Gary Goby recommends to landowners is to plant their walnuts at higher initial stocking and then remove the poorer trees at age five, leaving the best trees to grow at a final thinned spacing. According to Gary Goby, hybrid black walnut in western Oregon grows best in deep, well drained soils.
Black walnut prefers moister north or east facing slopes, and creek banks.
Shallow, dry or poorly drained soils should be avoided for new plantations. Landowners don't need to plant large acreages of black walnut to make a profitable investment, according to Goby. Clusters of black walnut trees can also be incorporated into riparian buffer strips. The initial spacing is usually 10-14 ft. between rows, depending on the size of the implements used for cultivation, and 10 ft. within the row. Although individual tree shelters are optional in the mild Oregon climate, some improvement in growth and protection from deer browse has been observed.