Oregon State University
view of annotated poplar gene

View of annotated poplar gene. A poplar gene on laboratory’s gbrowse site, showing intron/exon structure.


Greenhouse study of growth enhancing genes.  A study of genes for a plant hormone, gibberellin, that plays a major role in directing plant growth and development. 


A gene map.  Part of a recombinant bacterial plasmid used to insert genes into poplar. 

methylation density of of poplar genic regions in two tissue types

Methylation density of poplar genic regions in two tissue types. Density of cytosine methylation in two tissues of poplar near to a single gene.


Eucalypts in the greenhouse.  The trees were treated with a growth inhibitor to accelerate onset of flowering. 


Propagated poplars in a nursery.  The plants were multiplied for a research experiment. 


Poplar plants in Magenta boxes.  Plants have rooted and will provide tissues for gene insertion. 


DNA methylation along a poplar chromosome.  The boxes area shows variation in methylation among tissues (colored lines). 


Pollen in a poplar anther.  Pollen gains are formed and nearly ready for release. 


Gene expression in poplar leaves.  The blue “GUS” stain identifies a native poplar gene that is naturally expressed in vascular tissues.

flower close-up

Male poplar catkin. The flower was induced on a two-month-old plant in the greenhouse 


Poplar leaf expressing a fluoresce gene.  The Green Fluorescent Protein gene shows sites of active transgene expression in poplar leaves. 

autumn tree

Transgenic sweetgum in autumn.  The trees are growing and their leaves are senscening normally in a field trial. 

Field work

Field trial of genetically engineered trees.  A two-year old study of the effects of hyper-activating native poplar genes to help understand their functions (termed “activation gene tagging”). 


Transgenic Eucalyptus.  Blue color shows expression of a “reporter” GUS gene.   

Poplars in petri dish

Regenerating transgenic shoots in poplar. After double transformation with a gene to induce rapid flowering and a biocontainment gene, transgenic shoots are being produced for analysis.

field trees

Clone bank of transgenic poplars.  The trees will provide cuttings for a large field trial of genetic containment methods. 

Home Page

Hello and thanks for visiting my web page. We do research on means for improving the environmental sustainability of energy, wood, and paper production in trees using genomics (entire DNA) and genetic engineering methods.

I am a University Distinguished Professor housed in the Department of Forest Ecosystems and Society at Oregon State University, and have a joint appointment in the interdepartmental Molecular and Cellular Biology Program. I am also the creator and Director of the Tree Biosafety and Genomics Research Cooperative (TBGRC) at OSU, a university-industry consortium conducting research on genetically engineered trees that might be useful in forestry, bioenergy, and horticulture. For 9 years I directed the OSU Program for Outreach in Resource Biotechnology, aimed at promoting public understanding of biotechnology issues.

I earned degrees in biological sciences from Cornell, Yale, and the University of California at Berkeley; published more than 200 scientific papers; given more than 200 invited lectures; and earned more than 17 million dollars in research grants. I served on a number of scientific review panels at the United States National Research Council, National Science Foundation, and Department of Agriculture. I have been fortunate to have been recognized as Leopold Leadership Fellow, Forest Biotechnologist of the Year, and received the Barrington Moore Award from the Society of American Foresters. 

My research is focused on genomics and genetic engineering in eucalypts and poplar trees. Some of the focus areas presently are:

  1. Modification of flowering to reduce environmental and social concerns over gene flow from genetically engineered trees.
  2. Description of epigengenetic variation in the poplar genome during its growth and development; we are using "NextGen" sequencing of immunoprecipitated or bisulfite treated DNA to characterize changes in genome-wide methylation.
  3. The use of gibberellin signaling genes for modifying plant growth rate and form.
  4. The production of new biological plastics in tree leaves, as a possible renewable and carbon-neutral feedstock.
  5. Improved methods for insertion of genes and regeneration of transgenic plants in woody species.

I also study how government regulations affect the ability to do research and use genetic engineering for public and economic benefit, and am actively involved in public outreach and teaching about crop biotechnology generally. I teach in and coordinate an interdisciplinary on-campus and online course to give students and the public scientifically reliable information about the use of genes and chemicals in agriculture and natural resources.

I mentor high school, undergraduate, and graduate students on the potential of biotechnology to improve productivity and environmental soundness of agriculture and forestry, as well as about its ecological risks, social and legal issues, and ethical complexities. The laboratory usually hires or hosts several student research interns, especially in summer.

When not at work, I am a soccer referee at the high school and competitive club level, play tennis, hike, and run—all for fitness and relaxation. I prefer to walk and run in the many lovely forests and parks in Corvallis and the Oregon Cascade Mountains.