Fir and spruce trees are known for providing beauty and function in Nebraska. Unfortunately, they’re also known for being hard to diagnose when troubles arise.
With most trees and shrubs, specific symptoms are present when they are ailing from insects, diseases and abiotic maladies. That’s most trees and shrubs. Not so much with fir and spruce. In fact, over the years, I’ve sought out help from plant pathologists with diagnosis. Most of these requests have led to a shrugging of the shoulders and a couple of times running the other way!
The problem is this – whenever a spruce or fir is struggling, the symptoms they produce are the same, no matter the cause. They don’t produce round spots or marginal burning; just this sort of off color, sometimes purplish tint to the needles…sometimes falling off and sometimes not. That’s it. So, if the actual cause if overwatering or underwatering, root girdling or deep planting or a canker or root rot, the symptoms are the same.
Classic diplodia tip blight symptoms
Without helpful signs and appearances, we’re left to investigate in other ways. Gathering as much info as possible about the history of the site and noticing cues such as where the branches arise and how much growth has been produced in recent years is helpful. Looking closely at the trunk and pulling back the mulch or fallen needles is also a good step, as clues or better symptoms may be found there.
Fir struggling from deep planting. Photo credit (and feature photo): Cory Allan