Extension Service Site Publications

• (2022) Episode 28: Christmas Trees In this episode, Jacob Putney and Chal Landgren discuss the history and science behind growing Christmas trees in Oregon. Landgren is the former OSU Extension Christmas Tree Specialist.
  
• (2021) Christmas tree experimenting: what’s new and what stays the same after 40 years
• (2020) Christmas Tree Research Update
• (2021) A better method for controlling leader growth on Christmas trees Trying to control leader length on true fir Christmas trees has always been a tricky proposition. But now, after years of experimentation, a method using a plant growth regulator has proven successful.
• (2020) Promising new Christmas tree variety undergoing trials Trials are underway for a promising, new Christmas tree variety. The Trojan fir will undergo field trials that will evaluate traits including growth, needle retention and appearance. The trials will conclude in 2031.
• (2020) Cone harvests for noble fir seeds Every four years or so, noble firs produce a bumper crop of cones. One recent collection effort at two seed orchards yielded about 5,000 cones, enough seed for about 700,000 seedlings.
• (2019) Breeding Christmas Trees Oregon produces over 4.5 million Christmas trees.
  Chal Landgren researches Christmas trees in the Willamette Valley at the North Willamette Research and Extension Center.
  The goal isn’t to create picture-perfect Christmas trees.
  These trees are grown for breeding and cultural practices that benefit the Christmas tree industry.
  Full story here: https://oap.oregonstate.edu/2019/12/20/o-christmas-tree-how-lovely-is-thy-research/
• (2020) Woodland Notes Summer 2020 Woodland Notes Summer 2020 newsletter
• (2020) Persistent questions about growing Christmas trees The Extension Service Christmas tree specialist has answered thousands of questions over the years. Those questions usually lead to more questions that require careful observation and a detective's mindset to solve.
• (2020) Woodland Notes Spring 2020 Woodland Notes Spring 2020 newsletter
• (2020) Woodland Notes Winter 2020 Woodland Notes Winter 2020 newsletter
• (2020) Noble fir seedling survival strategies Christmas trees planted in unirrigated sites depend on the weather for survival. A research trial set out to find factors that would help seedlings survive during drought years. Results were mixed.
• (2019) What kind of live Christmas tree can survive in Central Oregon?
• (2021) OSU research keeps Oregon Christmas tree industry No. 1 in the nation Each Christmas tree species requires special skill and specific knowledge to be grown successfully.
• (2017) Comparison of noble fir progeny from US Pacific Northwest collection regions and Denmark for Christmas tree traits Noble fir is the leading Christmas tree produced in the US Pacific Northwest (PNW). This study is based on evaluations of 24,721 trees collected from five native collection regions in Oregon and Washington plus imported seed from Denmark. Traits important for commercial Christmas tree production were evaluated and include commercial height, tree grade, value and color.
• (1994) Nitrogen fertilizer: Where does it go?
• (2017) What is SERF Certification and why do it? Socially and Environmentally Responsible Farm (SERF) program is an environmental certification program for Christmas tree growers in Oregon and Washington.
• (2016) Developing Quality Christmas Trees in the Pacific Northwest
• (2011) Calibrating and Using Backpack Sprayers
• (2011) Shearing and Culturing Christmas Trees
• (2009) Christmas Tree Nutrient Management Guide for Western Oregon and Washington
• (2014) Identifying and Managing Christmas Tree Diseases, Pests, and Other Problems (Identificación y Manejo de Enfermedades, Plagas y Otros Problemas en Árboles de Navidad)
• (2017) Weed and Vegetation Management Strategies in Christmas Trees
• (2003) Growing Christmas Trees in the Pacific Northwest
• (2014) Best Management Practices for Christmas Tree Export (Buenas Prácticas de Manejo para la Exportación de Árboles de Navidad)
• (2006) Taxes and Assessments on Oregon Forestland and Timber