Purdue Landscape Report: We receive a large number of spruce samples each year at the Purdue Plant and Pest Diagnostic Laboratory (PPDL), with the vast majority being from Colorado blue spruce with ..

or produce a second flush of needles from defoliated stems. Rhizosphaera needle cast is a fungal disease, caused by Rhizosphaera kalkhoffii that attacks the needles of Colorado blue spruce in the ...

The American West is perhaps one of the nation’s most visually dynamic regions, and the blue spruce adds a distinct quality to this landscape. The blue spruce is the official state tree of both ...

Q: Over the past couple of years, the bottom branches of our Colorado Blue Spruce trees have been dying ... the chlorothalonil fungicide just after bud break and before needles are half elongated.

SALT LAKE CITY — SB41, a bill that would change the state tree from the Colorado blue spruce to the Quaking ... and is made up of an estimated 47,000 stems and trees, all of which originate ...

This is caused by the Eastern spruce gall aphid (adelgid), a well-known pest of Norway spruce and white spruce in the northeastern United States. Occasionally, it also infests Colorado blue spruce.