Chal Landgren

Christmas tree nutrient management guide for Western Oregon and Washington

This practical guide to managing nutrients in Christmas tree fields includes fertilization timing, soil and foliar testing and application methods to optimize tree growth and color.

John M. Hart, Chal Landgren, Richard Fletcher, Michael Bondi, Brad Withrow-Robinson, Gary Chastagner | May 2025 | OSU Extension Catalog

Weed and Vegetation Management Strategies in Christmas Trees

This publication offers an integrated approach to effective weed management in Christmas trees, incorporating diverse strategies and practices to keep weed populations off balance. It includes strategies for using ...

Ed Peachey, Chal Landgren, Tim Miller-Morgan | Nov 2021 | OSU Extension Catalog

Developing quality Christmas trees in the Pacific Northwest

Each Christmas tree species requires special skill and specific knowledge to be grown successfully. This publication outlines how trees grow and the culturing practices necessary to develop the size, shape, and ...

Chal Landgren | Jun 2023 | OSU Extension Catalog

Best management practices for Christmas tree export

This guidebook provides producers and shippers of Christmas trees with the tools to both identify and manage some of the export pests of greatest concern to trading partners.

Heather Stoven, Chal Landgren, Luisa Santamaria, Helmuth Rogg, James LaBonte | Mar 2023 | OSU Extension Catalog

Identifying and managing Christmas tree diseases, pests and other problems

Learn to identify and treat diseases, pests, disorders and damage affecting Christmas trees in this guide for tree growers and field workers.

Luisa Santamaria, Chal Landgren | Nov 2024 | OSU Extension Catalog