WSU Puyallup Thursday 8/20
Root rots and Seedling survival including Eurasian fir COFIRGE trial
- Field susceptibility of Eurasian fir species to Phytophthora root rot – the Rice Paddy experiments –Marianne Elliott and Gary Chastagner
- Effectiveness of fungicides in reducing Phytophthora root rot losses in Christmas tree plantations – Marianne Elliott
- Observations on the Conditions, Pests, and Diseases on Older Eurasian Firs in WSU Puyallup Research Trials – Gary Chastagner and Chal Landgren
- Identification of root diseases – Marianne Elliott and Gary Chastagner
- Mulch improves seedling survival by possibly retaining soil moisture and lower temperatures – Priya Rajarapu
- Monitoring drought stress – Marianne Elliott
Monitoring equipment for drought and seedling survival – Marianne Elliott and Gary Chastagner
USDA NRCS – Estimating soil moisture by feel and appearance
Quantifying Drought Stress Thresholds for Rehydration in Four Abies Christmas Tree Species – Niels Bertelsen, Marianne Elliott, Gary Chastagner
How growers can help measure moisture stress in Christmas trees - Are you sure you know what is killing your seedlings? Identifying causes of seedling mortality – Marianne Elliott
Tenlined June Beetle (WSU Tree Fruit) - CoFirGE-2: A national project to identify regionally adapted Trojan, Turkish and Nordmann fir to produce high quality Christmas trees– Chal Landgren and Gary Chastagner
Three-year performance of trees in CoFirGE-2 plots in Washington, Idaho, and California (Presentation at the International Christmas Tree Research and Extension Conference, June 2026) - Healthy Soils, Healthy Plants: Soils, Spaders, and Cover Crops –Doug Collins
WCCC (Western Cover Crop Council) webpage and cover crop species selector
Cranberry Lake Farm Friday 8/21
- Adelgids on Nordmann fir – Gary Chastagner and Marianne Elliott
- Current season needle necrosis – Marianne Elliott and Gary Chastagner
WSU and OSU Contact Information
Gary Chastagner, Professor Emeritus of Plant Pathology, WSU Puyallup, chastag@wsu.edu
Doug Collins, Extension Specialist and Soil Scientist, WSU Center for Sustaining Agriculture and Natural Resources; dpcollins@wsu.edu
Marianne Elliott, Plant Pathologist, WSU Puyallup, melliott2@wsu.edu
Chal Landgren, Professor- Emeritus, OSU Extension Christmas Tree Specialist, chal.landgren@oregonstate.edu
Todd Murray, Director WSU Puyallup Research and Extension Center. tmurray@wsu.edu
Priya Rajarapu, Assistant Professor, Christmas Tree Extension Specialist, Oregon State University, Priya.Rajarapu@oregonstate.edu