Article

Genecology of Douglas Fir in Western Oregon and Washington

USDA Forest Service, Pacific Northwest Research Station, 3200 SW Jefferson Way, Corvallis, OR 97331, USA.
Annals of Botany (Impact Factor: 3.3). 01/2006; 96(7):1199-214. DOI: 10.1093/aob/mci278
Source: PubMed

ABSTRACT Genecological knowledge is important for understanding evolutionary processes and for managing genetic resources. Previous studies of coastal Douglas fir (Pseudotsuga menziesii var. menziesii) have been inconclusive with respect to geographical patterns of variation, due in part to limited sample intensity and geographical and climatic representation. This study describes and maps patterns of genetic variation in adaptive traits in coastal Douglas fir in western Oregon and Washington, USA.
Traits of growth, phenology and partitioning were measured in seedlings of 1338 parents from 1048 locations grown in common gardens. Relations between traits and environments of seed sources were explored using regressions and canonical correlation analysis. Maps of genetic variation as related to the environment were developed using a geographical information system (GIS).
Populations differed considerably for adaptive traits, in particular for bud phenology and emergence. Variation in bud-set, emergence and growth was strongly related to elevation and cool-season temperatures. Variation in bud-burst and partitioning to stem diameter versus height was related to latitude and summer drought. Seedlings from the east side of the Washington Cascades were considerably smaller, set bud later and burst bud earlier than populations from the west side.
Winter temperatures and frost dates are of overriding importance to the adaptation of Douglas fir to Pacific Northwest environments. Summer drought is of less importance. Maps generated using canonical correlation analysis and GIS allow easy visualization of a complex array of traits as related to a complex array of environments. The composite traits derived from canonical correlation analysis show two different patterns of variation associated with different gradients of cool-season temperatures and summer drought. The difference in growth and phenology between the westside and eastside Washington Cascades is hypothesized to be a consequence of the presence of interior variety (P. menziessii var. glauca) on the eastside.

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    • "The sampling design we used for collection of seeds were based on results from an earlier genecology study conducted across the study area (St Clair et al., 2005). Seeds were collected across seven regions in Washington, Oregon, and "
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    • "With adaptation of populations to the climate being unequivocal (see St Clair et al., 2005), a change in climate will have an effect on the growth and survival of individuals and populations. Yet, for provenance test results to be useful in assessing potential impacts of climate change (see Mátyás, 1994), geographic descriptors of clinal variation must be replaced by climatic descriptors (see St Clair et al., 2005; Rehfeldt and Jaquish, 2010; Joyce and Rehfeldt, 2013). The primary goal of the present study is to synthesize disparate provenance test data so that range-wide, climate-based clines in the sub-specific varieties of P. ponderosa and P. menziesii can be described statistically. "
    Forest Ecology and Management 01/2014; 324:138-146. · 2.67 Impact Factor
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    • "aptation of P. spicata populations to multivariate climates when compared to other species. R 2 values for traits regressed on climate were between 0.51 and 0.28 (Table 7), compared with Douglas-fir (Pseudotsuga menziesii), for example, which had R 2 values of 0.68 and 0.50 for the first two multivariate traits in a canonical correlation analysis (St. Clair et al. 2005), and is considered to be closely adapted to environments when compared with other conifer species (Rehfeldt 1994b). The R 2 values found in the current study are similar in magnitude to those found for two genecology studies of grass species over a more restricted area in the Blue Mountains: E. glaucus with R 2 values between 0.51 and "
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