Skip to main content
U.S. flag

An official website of the United States government

Brad St. Clair

Brad St. Clair
Research Geneticist
Land and Watershed Management
3200 SW Jefferson Way
Corvallis, OR 97331-8550
United States
Current Research

My research is primarily aimed at understanding the genetic basis of how plants are adapted to their environments. Current research is focused on exploring responses of Douglas-fir populations from a wide range of source environments planted in a reciprocal transplant study using a wide range of test site environments. Results from this study will be valuable for understanding responses to climate change and exploring management options for adapting to future climates. In addition, I am developing Web-based tools that will help managers choose appropriate seed sources given different climate change scenarios. One of those tools is an archive for data from earlier provenance studies that will help prevent loss of this valuable information and promote collaboration to look at the data in new ways. Another major research focus are studies of geographic genetic variation in several grass species and implications for restoration after disturbances.

Past Research

My past research has focused on geographic genetic variation of Douglas-fir and implications for choice of seed sources. This work indicates that Douglas-fir populations are unlikely to be well-adapted to future climates, and that populations adapted to climates at the end of the 21st century would come from considerably lower elevations and from much further south. Other past research has concerned the conservation of genetic resources, tree breeding strategies, intergenotypic competition, ideotype breeding, and realized genetic gains.

Research Interest

My research interests are primarily concerned with describing and understanding geographic variation in how plants are adapted to their environments and the implications for management including reforestation, restoration, tree improvement, gene conservation, and responses to climate change. Species of interest include forest trees as well as grasses and forbs used in restoration projects. This research has contributed to guidelines for the movement of plant populations, genetic conservation needs, and natural and managed responses to climate change.

Why This Research Is Important
Ensuring the productivity, health, and sustainability of forests and grasslands requires knowledge of how plants are adapted to past, current, and future environments.
  • Oregon State University, Ph.D., Forest Genetics, 1989
  • University of Wisconsin, M.S., Forest Genetics, 1984
  • University of California Berkeley, B.S., Forestry, 1980
Featured Publications
Other Publications
Research Highlights

Century-Old Douglas-Fir Genetics Study Produces New Insights for Climate Change

Year: 2020
The 1912 Douglas-Fir Heredity Study - one of the first studies established by the US USDA Forest Service - is particularly valuable owing to its long timespan. While this study was established a century ago to help understand trait inheritance in Douglas-fir, it now provides new insights showing how...

Timing of flowering in Douglas-fir is determined by cool-season temperatures and genetic variation

Year: 2018
New model predicts Douglas-fir flowering to within an average of 5 days of observed flowering date. Warmer temperatures in the future will likely result in earlier flowering on sites that are currently colder during winter. Sites that are already generally warmer in winter may display no change, or ...

Climate of seed source affects susceptibility of Douglas-fir to foliage diseases

Year: 2018
Douglas-fir at higher elevations and in more continental conditions in the Pacific Northwest could experience more foliar diseases as local environmental conditions become warmer and wetter.

New tool puts the right seed in the right place for the coming climate

Year: 2017
The web-based Seedlot Selection Tool helps forest and restoration managers match seedlots with planting sites based on climate information.

The Douglas-fir Seed-Source Movement Trial Sheds Light on Responses of Adaptive Traits to Changing Climates

Year: 2016
This multi-site Forest Service study, encompassing a range of climate and soil conditions, is providing some very specific results on tree growth, survival, and diseases as well as responses in many physiological variables. Land managers in the Pacific Northwest are interested in the early results f...

New Seed Zones for Bluebunch Wheatgrass Tested

Year: 2015
New seed zones for bluebunch wheatgrass will help local, state, and federal land managers in the Interior Northwest to determine sources of bluebunch wheatgrass populations for postfire restoration. This research will inform the Native Seed Strategy by improving scientists’ understanding of methods ...

Provisional Seed Zones Developed to Guide Seed Source Decisions for Restoration of Native Species

Year: 2014
Forest Service scientists developed generalized provisional seed zones that can be applied to any plant species in the United States to help guide seed movement. The proposed provisional seed zones delineate areas of climatic similarity, which when combined with areas of general ecological similarit...