I have often relied on an identification trick of peeling off the needle to determine between spruce and fir on species that look very similar and with no cones present. Theoretically, a spruce tends to tear at the base of the needle whereas the fir pops right off leaving almost a perfect little circle where the needle was attached. My dilemma on this one comes from a sample my client sent in to a lab before he hired me to come out and they have identified the tree as a fir, but I was certain it was a spruce. If y'all can have a quick look at the photos and give me an opinion I would certainly appreciate it. Also, one of a group of three of these trees has almost turned completely brown with only some green growth left near the tips of the branches. Any thoughts on a potential cause of death? There is some heavy sap flow on the trunk low trunk, and the trees are about 25 - 30 years old.
Spruce; to be exact, Serbian Spruce Picea omorika. The most useful tip for telling spruces from firs is the twigs being very rough from the pulvini (persistent leaf stalks); firs have smooth twigs after leaf fall. Sorry, can't tell the cause of death from the pic.
Thanks, Michael. I was thinking the same thing, but when I see an email from a University I start to second guess. Hopefully someone might have some insight into possible causes of the die-back.
The quick'n'dirty way I learned to tell them apart is that spruce needles are 4 sided and you can roll them between your thumb and finger. Fir needles are flat and you can't, at least not easily.
