Role of genetics in restoration of southwest forest ecosystems

Restoration activities in the southwest require knowledge and application of both genetics and silviculture, and there are important information needs for restoration which have genetic and silvicultural components. Genetic criteria need to be developed to guide stand density reductions in ponderosa pine (Pinus ponderosa Laws) restoration if presettlement genetic diversity is to be maintained. Re-introduction of natural disturbance regimes such as frequent fire should include determining whether genetic adaptations to these disturbances still exist in the populations comprising the ecosystem. Douglas-fir (Pseudotsuga menziesii [Mirb.] France var. glauca [Beissn.]) restoration on Hopi land involves introducing new individuals due to the loss of most of the original populations. Genetic and silvicultural concerns include locating proper seed sources, selecting appropriate planting sites, determining the number of seed sources and genotypes to include in the restoration, making decisions on the spacing of the trees in the restoration efforts, and determining the timing of planting, the size, and type seedling to plant.