title: Survival and growth patterns of white spruce (Picea glauca [Moench] Voss) rangewide provenances and their implications for climate change adaptation.
abstract: Intraspecific assisted migration (ISAM) through seed transfer during artificial forest regeneration has been suggested as an adaptation strategy to enhance forest resilience and productivity under future climate. In this study, we assessed the risks and benefits of ISAM in white spruce based on long-term and multilocation, rangewide provenance test data. Our results indicate that the adaptive capacity and growth potential of white spruce varied considerably among 245 range-wide provenances sampled across North America; however, the results revealed that local populations could be outperformed by nonlocal ones. Provenances originating from south-central Ontario and southwestern Québec, Canada, close to the southern edge of the species' natural distribution, demonstrated superior growth in more northerly environments compared with local populations and performed much better than populations from western Canada and Alaska, United States. During the 19-28 years between planting and measurement, the southern provenances have not been more susceptible to freezing damage compared with local populations, indicating they have the potential to be used now for the reforestation of more northerly planting sites; based on changing temperature, these seed sources potentially could maintain or increase white spruce productivity at or above historical levels at northern sites. A universal response function (URF), which uses climatic variables to predict provenance performance across field trials, indicated a relatively weak relationship between provenance performance and the climate at provenance origin. Consequently, the URF from this study did not provide information useful to ISAM. The ecological and economic importance of conserving white spruce genetic resources in south-central Ontario and southwestern Québec for use in ISAM is discussed.
authors.affiliation: Ontario Forest Research Institute, Ontario Ministry of Natural Resources 1235 Queen Street East, Sault Ste. Marie, ON, P6A 2E5, Canada.
authors.forename: Pengxin
authors.initials: P
authors.lastname: Lu
authors.affiliation: Faculty of Forestry & Forest Environment, Lakehead University Thunder Bay, ON, P7B 5E1, Canada.
authors.forename: William H
authors.initials: WH
authors.lastname: Parker
authors.affiliation: College of Forestry, Oregon State University Corvallis, Oregon, 97331-5704.
authors.forename: Marilyn
authors.initials: M
authors.lastname: Cherry
authors.affiliation: Ontario Forest Research Institute, Ontario Ministry of Natural Resources 1235 Queen Street East, Sault Ste. Marie, ON, P6A 2E5, Canada.
authors.forename: Steve
authors.initials: S
authors.lastname: Colombo
authors.affiliation: Ontario Forest Research Institute, Ontario Ministry of Natural Resources 1235 Queen Street East, Sault Ste. Marie, ON, P6A 2E5, Canada.
authors.forename: William C
authors.initials: WC
authors.lastname: Parker
authors.affiliation: Ontario Forest Research Institute, Ontario Ministry of Natural Resources 1235 Queen Street East, Sault Ste. Marie, ON, P6A 2E5, Canada.
authors.forename: Rongzhou
authors.initials: R
authors.lastname: Man
authors.affiliation: Ontario Forest Research Institute, Ontario Ministry of Natural Resources 1235 Queen Street East, Sault Ste. Marie, ON, P6A 2E5, Canada.
authors.forename: Ngaire
authors.initials: N
authors.lastname: Roubal
keywords: Assisted migration; genetic conservation; genetic gain; geographic genetic variation; local adaptation; universal response function