Distinguishing Western Hemlock from Amabilis Fir

Tips on how to tell apart two very similar trees. April 20, 2006

Question
I was wondering someone might be able to help me with the identification or the differences between western hemlock and amabilis fir?

Forum Responses
(WOODnetWORK Forum)
From contributor A:
I recently asked the same question for a different species of Dr. Wengert and got this response back:

"Send a sample to the US Forest Products Lab in Madison, WI
Eugene Wengert, Emeritus Professor and Extension Specialist of Wood
Processing
President, The Wood Doctor's Rx, LLC
2872 Charleston Dr, Madison, WI 53711-6502
(608) 271-4441



From Gene Wengert, technical advisor Sawing and Drying Forum:
A quote from IDENTIFYING WOOD by Bruce Hoadley:
"I would rate hemlocks and firs as the most difficult of all conifers to separate visually." (He means using up to 10x magnification).Under the microscope, it is easy to separate the two using the presence of ray tracheid cells, which are found in hemlock and not fir.
(Note: He is talking about the true firs and not Douglas-fir.)


From contributor B:
There are easily identifiable differences in the leaves, cones and seed, even in silhouette. Looking at the grain of western hemlock vs amabilis fir shows their distinction clearly with a trained eye. I agree the average urbanite would have difficulty if they don't work with wood. You should be able to find tree identification keys to separate the two groups without digging out the microscope.

For example:
amabilis fir:
The seeds are heavier than seeds of most Pacific Northwest conifers except noble fir.
Seeds each contain a single wing but often fall from the upright cone axis by pairs on ovuliferous scales, as the bracts contort and tear themselves from the cone-a process that does not require wind.

western hemlock:
Empty cones often persist on the tree for 2 or more years. Cone scales of western hemlock open and close in response to dry and wet atmospheric conditions. Under wet conditions, seed may be retained in the cones until spring. Ripe cones are not upright. Hemlock seed germinates well on most any moist organic surface. You can often find a green carpet of seedlings germinated on a rotten log or sometimes in a standing dead tree stub (often western red cedar). Also, decent sized hemlock (12 inch dbh) can be found growing out of the top side of a rotten western red cedar log. Their roots will migrate around the log and into mineral soil under the log.