Basic Tree, Tree Identification, Regional and Community Forestry, School of Natural Resources
Colorado Blue Spruce, Horticulture, Landscape, and Environmental Systems
Great trees on NAIT campus - techlifetoday
Picea pungens (Blue Spruce, Colorado Spruce) North Carolina Extension Gardener Plant Toolbox
What's Wrong with my Blue Spruce? - American Conifer Society
Picea sitchensis, Landscape Plants
Spruce, Blue or Colorado Blue, TreeBrowser
Picea pungens var. glauca, Maud Gordon Holmes Arboretum
Why is my evergreen turning brown and losing needles? - Gardening at USask - College of Agriculture and Bioresources
Picea sitchensis, Landscape Plants
Landscaping Guide for Colorado Blue Spruce, Blog