The Christmas Tree program at OSU receives valuable assistance from crop specialists and Extension agents from a number of disciplines and locations across OSU. Recent retirements and position changes have thinned these ranks beginning in 2012. This type of web resource will likely become a prime source of information in trying to maximize scarce time and budgets.

Chal Landgren is the OSU Extension Christmas Tree Specialist for Oregon. His program covers information from site preparation through harvest. Current extension and research efforts include sustainability certification, tree selection/breeding and fertilization.

Latest Publication available for purchase:

Identifying and Managing Christmas Tree Diseases, Pests, and Other Problems PNW 659


IPM in Christmas Trees Workshop Materials

IPM-A conceptual and practical overview, Paul Jepson-OSU

IPM and Pesticides, Bruce Alber-Wilbur Ellis

Developing a treatment plan, Chal Landgren-NWREC-OSU

Identifying Root Rot in Conifers, Kathleen M. McKeever-WSU Puyallup Research & Extension Center


Associations and Organizations:

Pacific Northwest Christmas Tree Association

National Christmas Tree Association

Soil & Water Conservation Districts

ODA Pitch and Needle Newsletters

Production and Management:

Christmas Tree Nutrient Management Guide

Pest Management Strategic Plan for Christmas Trees in Oregon, Washington and Idaho

Growing Christmas Trees in the Pacific Northwest-PNW 6 publication

Buy-Sell Directory and Resource Guide


Industry Statistics and Regulations:

NASS/National Agricultural Statistics Service-

Christmas Tree Shipping Regulations


November 1, 2005

Information and strategies for field growers on how to reduce weeds in their crops. Topics discussed include, field preparation, sanitation, cultural practices and proper herbicide selection and use.

April 1, 2006

A comprehensive guide for forest managers, Christmas tree growers, and forest-tree nursery operators in Oregon and Washington on sudden oak death, the disease caused by the recently introduced Phytophthora ramorum.

December 1, 2003

Very informative and useful publication for nursery management and workers. Discusses the history of Phytophthora ramorum in Oregon and its biology, hosts and symptoms. In depth information on the management and prevention of the pathogen.

March 5, 2012

A discussion about live plant imports as an important invasion pathway for non-native plant pests. The authors discuss the effect of current regulation, the need for updated regulation, and the recent and proposed changes to plant import regulation.

January 1, 2012

A systems approach for the production of healthy nursery stock. The manual, published by the Oregon Association of Nurseries, is divided into 3 main parts. A systems approach introduction, voluntary best practices for your nursery, and the next step: systems approach certification.

June 1, 2012

Researchers report on a study conducted to test the efficacy of soil additives in promoting plant growth and reducing mortality. The species included in the trial were Hydrangea macrophylla ‘Endless Summer’, Berberis thunbergii ‘Rose Glow’, and noble fir (Abies procera).

June 27, 2003
A guide for the prospective and novice Christmas tree grower. Includes how to evaluate risk and potential for return. Discusses the tree growing cycle, tasks and time requirements, pertinent laws and regulations, and costs, returns, and taxes. Describes 11 popular species (color photos) including their soil and site preferences, pest and disease susceptibilities, and relative market value. References. 40 pp.
January 23, 2013
Christmas tree specialist, Chal Landgren, gives an update of shipping and exporting issues, disease and pest management and current resources for growers.
January 1, 1988
Northwest Christmas Tree Association (NWCTA) and Oregon State University conducted studies testing various Nobel fir and Douglas fir provenances for possible new Christmas tree sources. Tables provided ranking Nobel fir progeny and test sites.
September 1, 2009
This guide is designed to help Christmas tree growers learn to assess a plantation’s nutritional needs based on soil and foliar analyses and rotational timing. It will help you design strategies for effective nutrient applications and produce high-quality trees with minimal negative environmental impact.
Informative look at weed identification and control in Christmas tree production by Oregon State University affiliated researchers, Ed Peachey and Chal Langren.
September 1, 2012
A report on a current marketing outreach campaign which partners Christmas tree growers in Oregon and Washington with Oregon State University extension agents to promote real Christmas trees in major consumer markets.
Information provided on Christmas tree seed sources and a review of research and collections in Turkey by Oregon State University affiliated researcher, Chal Landgren.
January 1, 1993
Discusses how to select a plantation, choose quality seed, prepare the ground for planting, lay out a plantation, plant stock, manage weeds and pests, and plan for the next crop. Describes preshearing, basal pruning, shearing techniques, and shearing tools. Provides a year-by-year cultural schedule that covers planting to harvest. Includes 3 tables, 15 figures, and sources of additional information.
August 1, 2010
Research was conducted at Oregon State University North Willamette Research and Extension Center with the objective of determining whether the addition of foliar fertilization would benefit a Christmas tree plantation or container-grown conifer operation.
August 29, 2011
Fumigation treatments (a conventional methyl bromide – chloropicrin application and reduced-rate alternative fumigant treatments) and a nonfumigated treatment were evaluated at forest nurseries in Oregon and Washington for their effects on soil pathogen populations, weeds, and seedling morphology.
May 1, 2011
In an attempt to identify Pythium species (common dampening off pathogens) associated with forest nursery soils, field surveys were conducted at three forest nurseries (two in Oregon and one in Washington) in 2008 using three isolation methods.
June 1, 2006
The purpose of this study was to determine the persistence, measured as efficacy against BVW larvae, of M. anisopliae in five (coir, fir bark, hemlock bark, peat moss and perlite) common components of soilless potting media.
January 1, 2006
Research report detailing a study conducted on the involvement of polyamines (PAs) in the interaction between Pinus sylvestris L. seedlings and an ectomycorrhizal fungus Suillus variegatus (Swatz: Fr.) O. Kunze in an in vitro cultivation system.
January 1, 1998
USDA-ARS affiliated researchers tested the hypothesis that: (1) IAA concentration of mycorrhizal conifer roots is influenced by the in vitro (IAA and ethylene) production capacity of their associated ectomycorrhizal fungi; and (2) increased concentrations of root IAA cause an increase in root growth resulting in improved seedling growth and survival.
January 1, 2000
An experiment was conducted to determine whether application of plant growth regulators (PGRs) or moisture retention materials could modify IAA concentrations in roots, new root growth, and above ground plant growth. Douglas-fir, Englemann spruce, western larch, and lodgepole pine species were used.
January 1, 2000
A report on how the application of specific plant growth regulators (PGRs) and a moisture retention gel to the root systems of Douglas-fir can influence root indole-3-acetic acid (IAA) content, and tree growth and survival 10 years after planting in a clearcut.
November 1, 1990
A comprehensive guide for determining the difference between nonliving and living causes of plant damage. The authors also provide a list of available references for identifing plant problems, references topics vary from general plant problem diagnosis to crop specific.
March 1, 1989
The Oregon State University affiliated author discusses several pests of conifers and possible controls. The pests addressed include an eriophyid mite ("leaf vagrant" type), coneworms (Dioryctria), and a spider mite (Eotetranychus libocedri).
September 1, 1988
Information provided on cold injury occurring during dormancy. Specific topics addressed include; the effects of freeze damage, cold tolerance between plant tissues, winter sun scald, frost cankers or bark splitting, and winter drying of evergreen foliage.
July 1, 1988
The comprehensive guide to pruning shrubs is broken down into three main categories; plants flowering on current years growth, plants flowering on old growth, and plants grown for special effects. The author also addresses problems, solutions, and conclusions in relation to pruning shrubs.
July 1, 1988
The Michigan State University affiliated author addresses the issue of desiccation of bare-root nursery stock. Topics of discussion include; conditions that increase the probability of desiccation, most susceptible phases for bare-root stock desiccation, and control methods.
September 1, 1986
The author discusses the importance of noxious weed control in nursery crops along with chemical control methods. Specific noxious weeds identified in nurseries include yellow nutsedge, quackgrass, Canada thistle, field bindweed, horsetail rush, blackberries, and dandelion.
April 1, 1987
Increased interest in using biological control of insects by nurseries prompted the author to provide the brief report on using pathogenic nematodes for insect control. Topics discussed include nematode species, nematode lifecycle, host insects, and other factors.
December 22, 2009
Final report on research project comparing different methods of fertilization of field grown conifers and also containerized conifers. Study covers methods used, products tested and results obtained.
September 1, 1986
An informative discussion regarding eriophyid mites and their effect on Scotch, Australian, red, and white pines. Symptoms of eriophyid mite injury on pines, biology and control methods, and monitoring are the topics the author focuses on.
November 1, 1986
Growers guide for adjusting fungicide and bactericide rate use amounts in water for foliage plants. Author provides information on rates of use for many different fungicides and bactericides, specifically offering amounts for smaller rates of use.
April 1, 1985
The results of an Oregon State University affiliated two year study on the nutrient levels of Douglas-fir trees on Oregon Christmas tree plantations. Samples were taken from trees four and five years old in the Corvallis, OR and Willamette Valley areas.
April 1, 1985
Grovesiella canker caused by the fungus Grovesiella abieticola was known to infect True fir in Northern California and B.C. Canada but was discovered on Noble fir Christmas tree farms in Western Oregon and Washington in the mid-1980's. Descriptions of the fungus and control methods are included in the article.
July 1, 1984
Swiss needle cast (Phaeocryptopus gaumanni) is a fungal disease of Douglas-fir trees, native to the North American pacific coast, which causes needle and color loss. Topics discussed include, winter-spring symptoms, summer-fall symptoms, and control.
July 1, 1984
The use of photoperiod as a management tool to achieve optimal plant growth and development in a nursery or greenhouse environment. The information provided includes explantations of photoperiod; how it works, its importance to the grower, and the various effects of photoperiod manipulation.
April 1, 1985
The silver-spotted tiger moth, Halisidota argentata, belongs to a family of stout bodied moths which can be pests of conifers, causing loss of harvestable trees for Christmas tree growers. Lifecycle, habitat, appearance, and control methods are briefly addressed.
Forest Phytophthoras of the World is an international resource for the latest information on ten major species of Phytopthora.
June 1, 2004
Includes identification and management information for eight weeds commonly found in Oregon container nurseries. Color photos and descriptions of weeds throughout their life cycle aid in identification. Presents control strategies for each weed.
December 1, 1986
A close look at a serious pest of many conifers commonly grown in nurseries throughout the Pacific Northwest. Article examines the host range, life cycle, damage, monitoring, cultural prevention and control as well as chemical controls.
December 1, 1986
Research was conducted on moisture loss from Douglas-Fir Christmas trees at Oregon State University from 1981-85. The author discusses the objectives and results of the 4 year study and their effects on the Northwest Christmas tree industry.
July 1, 1976
Research was conducted to gain incite into the fungal disease, Lophodermium needle cast, affecting Scotch pines in the Pacific Northwest. The most susceptible species were considered to be Scotch pine (Pinus sylvestris), red pine (Pinus resinosa), and Monterey pine (Pinus radiata).
November 1, 1981
The idea of using clones in the Christmas tree industry is debated by the Oregon State University affiliated author. The use of clones could lead to more uniform sellable trees but could also lead to a lack of genetic diversity in the Christmas tree industry.
February 1, 2004
Guide for growers west of the Cascade mountains growing in native soils. Topics include optimum pH levels for commonly produced crops, understanding pH and how to measure it correctly, problems and symptoms of too high and too low soil pH, and solutions for pH extremes.
September 1, 1987
A brief summary of a research project which evaluates the herbicide Sethoxydim (Poast) for grass weed control and phytotoxicity in conifer seedling beds. Three conifer species, Abies procera (noble fir), Pinus sylvestri s (Scotch pine), and Psuedotsuga menziesii (Douglas-fir) were used.
June 1, 1971
The future of research and extension work in the ornamental industry at Oregon State University is discussed by the author. Research and extension staff worked to identify areas in need of research and established priorities with in those areas.
April 1, 1977
Water availability for the upcoming growing season was a concern due to an unusually dry winter. The author discusses the legalities of Oregon water rights regarding greenhouse and nursery crops. Several different types of irrigation permits are addressed along with where to obtain them.
January 1, 1982
Douglas-fir needle midges are discussed in regard to their impact on Christmas tree production. The topics specifically addressed are; midge descriptions, building emergence traps, chemical control, cultural control, physical control, and biological control.
August 1, 1988
A discussion on the importance of storage factors for best survival of conifer seedlings. Many prestorage and storage factors affecting survival and growth of the outplanted seedling include lifting date, dormancy, prestorage handling, packaging, storage temperature, water relations, mold control, and storage duration.
December 1, 1971
Based on a previous article calling for research in the ornamental crops industry in Oregon, the authors elaborate on what ornamental and horticultural areas need more research. Specific crops are listed along with the most pertinent areas for each crop needing more research.