Jul 12, 2022OSU hazelnut orchard program update
We are well into another busy field season in the Orchards Program, and we are happy to have returning students and one new student this year. Bio Science Research Technician Kody Transue has our research orchards in great shape.
Mowing has been a constant orchard task with the rain this spring. The team had to thin some of our double density plantings this winter after just six seasons because of the strong growth on irrigated trees. It was getting very difficult to
perform single–tree harvest for research with the crowded trees. It will be interesting to see how the permanent trees respond over the coming seasons.
The cooler, wetter weather has delayed irrigation research in the hazelnuts, but we have some new projects getting geared up on water stress research in addition to our consistent evaluation of growth and yield response to hazelnuts under different rates of irrigation. We are collaborating with USDA–ARS engineer Jason Kelley on some new instrumentation to monitor evapotranspiration in hazelnut orchards.
We are happy also to have an exchange PhD student Gessica Altieri from Pontenza, Italy. Gessica will be doing independent research on drought stress and stomatal regulation in hazelnuts. We continue to work on nonstructural carbohydrate (NSC) production in hazelnut orchards throughout the Valley in cooperation with the Carbohydrate Observatory at University of California, Davis. We think NSC is key to understanding and predicting hazelnut production and environmental response.
We are wrapping up a project with the Oregon Department of Agriculture Fertilizer Program looking at nitrogen uptake and partitioning under different irrigation regimes. We did not plant any new hazelnut orchards this season, but we are excited to start working with a plot we established last year to evaluate the performance of trees planted in single, double and triple density. For these higher densities, we will be utilizing summer pruning and ultimately hedging to maintain small tree size.
Aphids are a major theme of pest management research activities in hazelnuts these last few seasons, and we are seeing high numbers in the field at cooperator orchards. We have research on aphid management tactics, and we are evaluating damage, phenology and biological control.
Undergraduate researchers Matt Pedersen and Tate Keyes are doing some great independent research projects on biology of filbert and hazelnut aphid and use of entomopathogenic fungi against these species. We are collaborating with Luisa Santamaria’s plant pathology program on this work, which has been great.
Master of Science student Erica Rudolph is in her second and final field season, and she is getting ready for emergence of Pacific flatheaded borer from infested hazelnut and other wood we collected over the fall and winter, and her traps are deployed and ready to capture the winged adults.
Erica is also working on a big project with Nutrien and FMC to evaluate automated filbertworm traps at more than 100 sites across the Valley. Claire Donahoo is a PhD student that is studying the establishment of Trissolcus japonicus, an egg parasitoid natural enemy of brown marmorated stink bug (BMSB) and is in her last field season. The wasp is reaching a level of establishment that will benefit specialty crop producers and homeowners alike.
Last year, there were few impacts from BMSB in orchard crops, but we are already catching good numbers in orchards this year. We have several product trials this season, as well. As usual, faculty research assistant Heather Andrews does a great job overseeing a lot of the research projects (especially insect-related) and she is up for promotion this year.
– Nik Wiman, associate professor and orchard specialist, Oregon State University