I apologize for this tardy response but I have been out of the office for
a couple of weeks.
On Mon, 11 Mar 1996, Andrew Gray wrote:
> I've heard this comment about old practices of "new" forestry in
> the Pacific Northwest too many times to let it slide. If you're
> referring to the "new" forestry reported in Isaac 1956 ("Place of
> partial cutting in old-growth stands of the Douglas-fir region",
> Pacific Northwest Forest and Range Experiment Station, Research Paper
> #16), I suggest you re-read it a little more carefully. The studies
> reported in that paper were done in old-growth stands (a practice not
> contemplated by "new forestry") and were, if you read the methods,
> basically high-grading operations. Thus it was no surprise that
> survival and growth of residual trees was poor. It was a half-hearted
> attempt, at best, to try something other than clearcutting in PNW
> forests. If there are other studies that you refer to, please cite
> them. (I would agree, however, that Leo Isaac and many of his
> contemporaries made many valuable contributions to forestry and
> ecology and are still well worth reading.)
>
> Andrew Gray
> graya@fsl.orst.edu
> =========================================================================
Thank you for clarifying the role of "new forestry". That its use
in old-growth stands is "a practice not contemplated" comes as a welcome
surprise to some of us (2,8).
It certainly can be argued that during the thirties and forties
the FS made more than a "half-hearted attempt" at finding and applying an
alternative to clearcutting (7). These operations were done with full
awareness of the dangers of high-grading - in fact a reading of the
individual stand treatments in the reference given (4) illustrates the
variable nature of "high-grading" as it was applied to FS sales. For
example we read: "Care was taken in marking to leave good trees well
distributed over the area, but the wolf trees were not taken because they
were in large openings." And on the same page (different stand) we also
read: "Mostly sound trees were cut. The reserve stand of more than 100,000
feet per acre was only 20 percent in completely sound trees, and about
half of the volume was in completely cull trees."
The reference cited (4) is quite good. I would add at least two
additional starting points to the literature of that time frame (3,6). It
is unfortunate that much of the silvicultural and forest management work
of that era is poorly referenced and of somewhat limited availability.
My personal objection to the term "new" is based primarily on what
I have seen being applied in the field under the name of new forestry.
Most, but not all of my observations are based on the application of new
forestry concepts to second growth Douglas-fir forests. It would seem that
we have forgotten some hard won silvicultural concepts and are sacrificing
the productivity of our forest land for the chimera of short term
political acceptability. Reproduction and protection of Douglas-fir stands
on some of our most productive land appear to be severely threatened by
practices discredited at great cost by previous research. Perhaps the
reluctance on the part of some foresters to immediately embrace this "new
forestry" is best summarized by a quotation from an article by Thornton T.
Munger, former silviculturalist and director of the PNW For. Exp. Sta. in
Portland (7):
"This in brief is a chapter in the history of cutting practices in
the Douglas-fir region. For a few years foresters strayed rather far
afield in disregard of nature's biological principles. As an experiment it
has been valuable. Without experimentation there would be no progress. But
in this case a revolutionary practice was adopted wholesale before the
results of experimentation were available.
"This chapter of silvicultural history has a moral for the
profession especially since it is only one of three instances I might cite
when foresters in this region plunged headlong into some new practice,
impelled by the claims of its promoters, before making scientific
appraisal of all aspects of the new proposal. Silviculture is an art that
should base its practices on the proven findings of many sciences. It must
be practiced consistently over a long term of years. It should not be
swayed by considerations of passing expediency or popular appeal. Let
foresters keep to their science of silvics. And let us keep research ahead
of practice so that untested innovations will not get ahead and get off
the trail of nature's silvical laws."
(1) Boyce, J.S. (1932) Decay and Other Losses in Douglas-fir in Western
Oregon and Washington. USDA Tech. Bull. 286.
(2) Gregg, N.T. (1991) "Will 'new forestry' save old forests?". Am. For.
97(9&10):4953,70.
(3) Isaac, L.A. (1943) Reproductive Habits of Douglas-fir. Charles Lathrop
Pack Forestry Foundation publication.
(4) Isaac, L.A. (1956) Place of partial cutting in old-growth stands of
the Douglas-fir region. USDA FS Res. Pap. No. 16.
(5) Kirkland, B.P. (1946) Forest Resources of the Douglas-fir Region.
(6) Munger, T.T. (1940) "The cycle from Douglas-fir to Hemlock". Ecology
21(4):451-459.
(7) Munger, T.T. (1950) "A look at selective cutting in Douglas-fir". J.
For. 48(2):97-99.
(8) Zuckerman, S. (1992) "New forestry; New hype?". Sierra
77(2):41-42,45,67.
=========================================================================
Date: Wed, 20 Mar 1996 16:14:47 -0700
From: Jim X Alegria <jalegria@SC0126WP.SC.BLM.GOV>
Subject: Re: OLD-GROWTH TERM - Reply
From:
H.J. Andrews and R.W. Cowlin, "Forest Resources of the Douglas-Fir Region"
United States Department of Agriculture Miscellaneous Publication No.
389 Washington D.C. December 1940.
"Stands more than 160 years of age were considered as a whole to have no
present net growth. although some stands above this age are increasing
in merchantable volume, others are actually losing in merchantable volume;
thus in these older stands losses due to mortality and to decay approximately
balance growth."
They later later split stands into "small old growth" and "large old growth"
based on the size of the trees at this age. The general definition for
old-growth, which is implied in the above quote, is the point of no net
growth. Where mortality equals growth.
Recently the definition of old-growth has taken on other meanings as many
of the respondents have pointed out but originally, it was simply a no
net growth issue.
Jim Alegria
USDI BLM
Portland , OR
========================================================================
This publication and one by Kirkland (5) are excellent points of
reference in the definition and use of the terms old-growth and
second-growth. With regard to the application of these terms in these two
publications a couple of observations seem in order. The referenced
investigations of Boyce (1) in the publications cited had shown that net
volume growth in site II D-f stands continued until about 300 years of age
(by which time most D-f on sites I and II would have in fact long been
classified as "large old-growth" by virtue of their diameters having grown
larger than 40 inches). As quoted above the 160 year cut-off was selected
because "Stands more than 160 years of age were considered as a whole to
have no present net growth". One way to read this sentence and those that
follow is that their estimates for regional volume figures were based on
the assumption that the small net gain of volume on all stands in the
region with ages from 160 to 300 compensated for the net volume loss in
all those stands in the region above 300 years of age. Bottom line....it
would appear that age and size (rather than a zero marginal gain in stand
volume) were the primary factors in classification. The authors
explicitly acknowledged ambiguity in the definitions stating: "As applied
to Douglas-fir here and elsewhere in this report, "old-growth" and
"second-growth" are relative terms distinguishing between the older timber
and the younger, more rapid-growing timber. Likewise, "large" and "small"
are used here as relative terms distinguishing between larger and smaller
timber of a given type or species." Also note the diameter overlap (22-40)
between "small old-growth" and "large second-growth" in Table 1 a clear
indication that size alone was not the sole determinant.
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