White fir and Grand fir

[Clark]

I'd like to hear from those that have worked around white and grand fir.  If you have, you probably know what the next question is: based on your field experience do you or do you not consider them to be two separate species and why?

Thanks.

Clark

[SwampDonkey]

I don't work in it and have never seen it other in a lab I saw grand fir cones and bows for ID.

But, one thing that separates them a bit is range. Grand fir is further north, into BC. Also, white fir needles have stomata on both leaf surfaces, while grand only has them below. Thusly, white fir gets it's name as these look white or give the needle a silvery sheen. Mature grand fir bark looks like hemlock to me.

[mtngun]

Wikipedia says they are two distinct species whose ranges overlap only in a couple of places, mainly the Southern tip of the Oregon Cascades.

However ......    the US Forest Service says "Grand fir crosses with both the concolor and lowiana varieties of white fir. Several studies have shown hybridization and introgression between grand fir and white fir in a broad zone extending from the Klamath Mountains of northern California through southwestern Oregon and through the Oregon Cascade Range into northeastern Oregon and west-central Idaho."    http://www.na.fs.fed.us/pubs/silvics_manual/Volume_1/abies/grandis.htm   

The Idaho Forests site says "The greenish hue of the grand fir's cones make them easy to distinguish from the white fir's olive-green to purple colored cones."    http://www.idahoforests.org/grandfir.htm

Just to confuse matters, locals here in Idaho commonly refer to Grand Fir as "White Fir."    :

Grand Fir is mostly used for pulp and for low grade dimensional lumber.    Sometimes it is not worth what it costs to haul to the mill, and loggers will burn it with the slash or just leave the felled trees to rot.     Firewood cutters don't like it because it has low BTU's and the knotty wood is tough to split.     Generally, it's considered a bit of a pest and a fire hazard.

[Clark]

First of all, none of the below thoughts are original to me.  I've met others who have had some or all of these thoughts before and certainly others before them thought the same.  I'm just hoping for some more input from those that have more experience in this area.

Swamp - Your point of stomata on either or one surface of the leaf is the only decent argument I've seen for classifying them as separate species.  However, the presence or absence of stomata doesn't necessarily make the difference between two species. 

Otherwise compare the descriptions of the two from a dendrology book and the similarities are surprising.  The fact that they have very different ranges indicates to me that this could in fact be the same species, just identified at separate times and places.

mtngun - I worked on the Payette National Forest several years ago.  During a training day (snore!) one of the botanists started in about grand fir and how this was a transition zone where many "hybrids" of grand and white fir could be found.  They readily accepted grand fir as the species code for any "hybrids" but what would we do if we found a true white fir?  Better yet, why couldn't they show us a white fir so we would know what they thought the differences were?

I for one don't think there are enough differences between the two to justify two species.  Classifying the trees as one species but with several varieties makes sense, much like is done with ponderosa pine.

Clark

[SwampDonkey]

the presence or absence of stomata doesn't necessarily make the difference between two species.

Why not? Flowers do it for a lot of separate species. Are you intimate with the flowers?

It's a true fir, but so aren't balsam fir and Amabilis fir which don't have stomata on both upper and lower surfaces. Subalpine fir does. But you may find some stomata at the tip of the others on the upper side, not always, but not the length of the upper surface.

Balsam Fir is hybridized only in the south of it's range into Fraser Fir. Needle morphology in fir as any tree depends on whether the branch is in full sun, shade, poor or rich soil, insect and disease stress. Heck, I've seen people look at branches up high from the ground, see next year's pollen cones on the branches, see this years cones disintegrated with the axis behind, and call it budworm damage.  I'm looking and looking, and asking where the heck is this budworm damage? :

[nsmike]

Just a comment on mtngun's situation in Idaho regarding Grand Fir. It's a preferred framing wood in the Midwest, so why might you ask, is it considered somewhat of a pest in Idaho? The simple answer is comparative economics, for western firs to make good lumber, they need to be kiln dried. When air dried it's subject to staining and thus only makes for a low grade product. When Kiln dried its only about 17% weaker than Douglas Fir. In BC, and other areas with comparatively low cost energ it can be kiln dried it and be profitable despite the fact it has, twice the water, and only sells for 2/3 the price of Dfir.

[Clark]

the presence or absence of stomata doesn't necessarily make the difference between two species.

Why not? Flowers do it for a lot of separate species. Are you intimate with the flowers?

That would be the rub right there Donk.  I vaguely recall a definition of "species" from botany that had to do with a population of plants/animals that could produce viable offspring.  Stomata have little, if anything, to do with that.  Flowers have lots to do with it and I really don't know anything about the flowers of either fir. 

I'll freely admit that when we get into things like "what is a species" and "what should/does differentiate different species" I am quickly getting beyond my area of expertise.  My interest in this issue lies in the fact that there are two species that are very morphologically similar and have geographic distributions that very nicely complement each other.  On top of it all, some quick research shows that grand fir was discovered by David Douglas in ~1830 and white fir by William Lobb during an expedition during 1849-1853.  Could it be that given the rate information was disseminated during the 1800's that Mr. Lobb didn't know about or have an accurate description of grand fir while on his expedition and presumed to have found a new species?  I don't know but will have to read up on it!

Clark

[SwampDonkey]

Possibly it has never been challenged, but I would think someone has studied the different trees in more detail over the years.

Read the story on this species.

http://en.wikipedia.org/wiki/Callitropsis_nootkatensis

[nsmike]

I'm not taking sides, but there's seems to be some some discussion of the subject here, http://www.conifers.org/pi/Abies.php. They seem to conflicted as to if they belong to a closely related sub family or just species variaton. The drop down menu under Taxon will bring up the individual species. They do show a list the studies they used.

[SwampDonkey]

There's no real sides, just discussion. ;)

Some people have a time of it with Fraser vs balsam fir. Some just call Fraser a variant.

[nsmike]

Perhaps sides is to strong a word, I don't know enough to take a position, but the discussion is interesting. I do know that every field of biology has it's conundrums when it comes to, sub families, species, and varient.

[stump farmer]

I've worked quite a bit around white fir and a little bit around grand fir. They appear to my limited exposure in the field (Sierra Nevada and northern California coast range) to be different in a few ways. The grand seems to be of better strength and health where most of the mature white fir I've seen have some sort of defect usually a dead top. White fir have much sap running down the bark and the ones that I've fallen usually have a substantial amount of rot and many times pungent fluid pours out of them during falling. White fir is known as pi-- fir locally. I read the writeups that state the two species only overlap briefly and I can't remember seeing them together but I'm no expert at tree ID.
In the Sierras white fir is looked at as an unwanted result of fire suppression efforts. Prescribed burns and mechanical thinning many times seek to reduce the number of white fir and select for sugar, jeffery and ponderosa.
For what it's worth the two trees are managed quite differently in this area and are seen as different trees during falling due to the white fir's propensity to have hazardous defects.