Mr Chairman, Senators, thank you for the opportunity to testify
regarding pending legislation to protect old-growth forests in Oregon
and Washington

My name is David A. Perry

I am a Professor (emeritus) in the Department of Forest Science, Oregon
State University.

I am a member of the National Commission on the Science of Sustainable
Forestry, and serve on the Board of Directors of the National Center for
Conservation Science and Policy. I am a former member of the Marbled
Murrelet Recovery Team, The Scientific Societies Panel on Interim
Protection for Old Growth Forests in eastern Oregon and Washington, and
the National Research Council's Panel on Environmental Issues in Pacific
Northwest Forests.

I'll begin by quoting a central recommendation of the National Research
Council's Committee on Environmental Issues in Pacific Northwest Forest
Management (NRC 2000):

*Forest Management in the Pacific Northwest should include the
conservation and protection of most or all of the remaining
late-successional and old-growth forests.... The remaining
late-successional and old-growth forests could form the cores of
regional forests managed for truly and indefinitely sustainable
production of timber, fish, clean water, recreation, and numerous other
amenities of forested ecosystems.*

Note the terminology used here differs somewhat from other uses. By
"late-successional", the NRC panel refers to what is also called
"mature", the seral stage immediately preceding old-growth.

In the following I'll first discuss the common definitions for
old-growth and its current status as compared to historic. I'll then
briefly go into the ecological rationale for protecting what remains.
I'll close by discussing mature forests and the rationale for protecting
them as well as old-growth.

**I. Defining Old-Growth**

Both old-growth (OG) and mature are best defined by their structure
(which may vary with forest type). From an ecological standpoint, the
most accurate definition for OG is that given by the National Research
Council Panel of Environmental Issues in Pacific Northwest Forests (NRC
2000)

Old-growth forests are forests that have accumulated specific
characteristics related to tree size, canopy structure, snags and woody
debris and plant associations. Ecological characteristics of old-growth
forests emerge through the processes of succession. Certain features -
presence of large, old trees, multilayered canopies, forest gaps, snags,
woody debris, and a particular set of species that occur primarily in
old-growth forests - do not appear simultaneously, nor at a fixed time
in stand development. Specific attributes of old-growth forests develop
through forest succession until the collective properties of an older
forest are evident

It is generally accepted that forests develop the full set of OG
characteristics by 180 to 220 years, although as the NRC definition
indicates there is no sharp dividing line and forests usually begin
displaying OG characteristics at a younger age; I will refer to these as
"emergent OG". Note also that not all of the characteristics cited in
the above quote hold in all forest types. In particular, multi-layered
canopies are not a characteristic of old-growth pine on dry sites.

II. **The current extent of old-growth forests in Oregon and Washington
    is only a small fraction of the original.**

The amount of OG at the time of European settlement varied by region,
but for the two states together is estimated to have composed nearly
two-thirds of the total land area of western Oregon, western Washington
and the east slopes of the Cascades (Strittholt et al 2006). Historic
proportions in the Blue Mountains, Klamath Plateau, and Colville area
were similar; a USFS inventory of the latter three areas in the
mid-1930's classed 65 per cent of forests as either as OG or, in types
where OG wasn't distinguished, as "large". This was after a 20 year
period of heavy logging, so it is reasonable to assume that the
pre-logging area of OG forest in the eastern portions of the two states
was even greater than in the western portions.

Strittholt et al (2006) used remote imagery to document current OG
amounts in western Oregon, western Washington, and the east slopes of
the Cascades (forests within the range of the northern spotted owl
(NSO). At the turn of the 21^st^ century approximately 28 per cent of
the original OG remained, largely concentrated on public lands
(Strittholt et al. 2006). One-third of the OG remaining on public lands,
representing approximately 7 per cent of the original, is in relatively
secure protected status ( e.g. Wilderness, National Parks). OG contained
within Late Successional Reserves and Designated Roadless Areas is less
securely protected (e.g. the recent attempt by the USFWS to include a
no-LSR option in the draft NSO Recovery Plan), but including these areas
increases the proportion of original OG within the range of the NSO that
is presently in protected status to approximately 14 per cent. Remote
imagery detects complex canopy structure rather than age per se, and
it's almost certain that the OG cover measured by Strittholt et al
(2006) includes emergent OG stands that are younger than 180 years.

In eastern Oregon and Washington outside the range of the NSO, Henjum et
al. (1994) estimated that one-quarter of the original OG remained on
National Forest Lands in the mid-1990's, 22 percent of which was
protected in Wilderness or administratively withdrawn areas. Less than
one-half of the areas designated as "dedicated old-growth" contained
more than 70 percent OG, and nearly one-third contained none (Henjum et
al. 1994). Logging all unprotected OG in the eastern regions of the two
states would reduce that remaining to approximately 5 percent of the
original.

**III. Values of OG: Habitat**

There is little question that "(m)uch of the biological diversity of the
Pacific Northwest is associated with (mature) and old-growth forests"
(NRC 2000).

From the standpoint of conservation ecology there are at least six
reasons for protecting all remaining OG:

-   The science is clear: when habitats have been sharply reduced the
    probability of maintaining viable populations of organisms that
    depend on those habitats increases directly with the amount of
    remaining habitat protected. The amount of OG currently protected in
    Oregon and Washington is far below the minimum amounts of habitat
    that conservation biologists believe is necessary to maintain
    species viability (Noss and Cooperrider 1994). Protecting all
    remaining OG (as detected by remote imagery) would raise levels into
    the low range of that considered adequate.[^1] Moreover, saving all
    would provide an important buffer against future losses. Natural
    disturbances are likely to destroy some of the remaining OG and
    mature habitat before younger forests have aged sufficiently to
    provide suitable replacement habitat, a risk significantly increased
    by the combined effects of changing climate and the increased
    vulnerability of older forests when embedded within a matrix of
    fire-prone young forests. On the east slopes of the Cascades, 14.5%
    of NSO habitat was lost between 1994 and 2003 (Spies et al. 2006),
    and approximately 80,000 acres of NSO habitat was lost in the
    Biscuit fire. The more saved now, the greater the buffering against
    such losses

-   Many species that occupy stable habitats---of which old forests are
    a prime example---have poor dispersal capabilities, hence risk
    isolation, genetic deterioration, and ultimate extinction when
    suitable habitat is spread too widely (Kareiva and Wennergren 1995).
    Studies suggest that many OG associates in the PNW may be limited
    more by dispersal than by the abundance of habitat per se, including
    species of lichens, bryophytes, mollusks, fungi, and invertebrates.
    This implies that every remaining piece of suitable habitat becomes
    an important focus for eventual colonization of the surrounding
    landscape. Potential problems with dispersal are exacerbated in the
    Pacific Northwest because young forests presently dominating the
    matrix do not have the structural complexity and legacies
    characteristic of naturally disturbed forests (e.g. Tappeiner et al
    1997), resulting in a much starker contrast between old and young
    forests than occurred historically.

-   Species, species assemblages, and the genetic structure of
    populations may vary at relatively fine scales for small organisms
    (which account for by far the largest share of diversity), raising
    the possibility that each remaining older forest is to some degree
    unique in its biological structure. For instance, many mollusk
    species are restricted to one region, or even one river drainage
    (Frest and Johannes 1993).

-   Even small fragments of older forest may be significant biological
    reservoirs. Amaranthus et al. (1994) found that 3.5- ha fragments of
    mature forest harbored 13 species of truffle-forming mycorrhizal
    fungi not found in surrounding plantations.

> **IV.Other values of OG**

OG forests store large amounts of carbon that may take to several
hundred years to recoup following logging. Some OG stands, especially
those with infrequent fire regimes, accumulate large stores of carbon in
the soil compared with mid-aged forests. .

OG has a strong influence on stream flows relative to younger stands. In
an experiment comparing logged and unlogged basins in the Cascades,
logged basins have had elevated stream flows for 40 years compared to
their OG controls (Jones and Post 2004). Stream flows during the
snowmelt season have been particularly slow in recovering to OG
conditions. Another experiment that compared logged with 100 year-old
forest rather than OG has shown a similar pattern.

Considerable evidence over the past two decades shows that OG is more
resistant to crown fire than younger forests, and hence helps buffer the
landscape against the possibility of mega-fires. Modeling shows that
western Oregon is likely to become drier with climate warming, which
means more fire and therefore an increased value of relatively resistant
components on the landscape.

The situation with fire is complicated in the dry forest types, where
various factors have allowed understory fire ladders to develop in OG
forests, increasing their susceptibility to crown fires. Appropriate
levels of fuels reduction are badly needed in many these dry forests,
however at least three strict guidelines should be followed. First,
large, fire resistant trees should be retained. Second, habitats for
closed forest species should be protected, which means taking a
landscape approach to thinning. Third, all caution should be taken to
protect soils and streams.

> **V. Mature Forests**
>
> As recognized by FEMAT, a conservation strategy for the Pacific
> Northwest must consider mature forests as well as OG. Forests are
> considered to enter maturity when their mean annual increment
> culminates, following which time they begin developing the
> characteristics that ultimately produce OG. Mature forests serve
> various important ecologic functions. They serve as future
> replacements for old-growth, help protect existing OG by reducing the
> starkness of age-class boundaries, and provide landscape connectivity
> and transitional habitat that compensate to some degree for the low
> levels of OG. Moreover, they are almost certainly more resistant to
> crown fires than younger forests, and hence contribute to buffering
> the landscape.

According to FEMAT, mature and old-growth forests together compose
approximately 51% of federal forest lands within the range of the NSO in
Oregon and Washington. Protecting all of these would have clear benefits
from the standpoint of conservation and landscape ecology. A majority of
the landscape dominated by large trees within forests that have or are
developing complex structure provides habitat connectivity for
late-successional species and lowers the risk of mega- wildfires.
Complete hands-off is not necessary, and in the case of dry forests,
management will be required to reduce fire hazard. In mesic forests
there is unlikely to be any ecological justification for thinning in OG
and older mature forests, however thinning may be both appropriate and
beneficial in some younger mature stands. Such evaluations must be made
on a case-by-case basis and involve both silvicultural and habitat
considerations.

In summary, OG forests are centers of biological diversity, perform
unique functions with regard to carbon storage and hydrologic
regulation, and serve as relatively stable components of the landscape.
Mature forests share many of the OG values. The area of OG has been
sharply reduced compared to historic conditions, and amounts currently
protected are well below scientifically accepted minimum habitat levels
required to maintain species viability. Saving all remaining OG forests
greatly enhances the probability of late-successional-dependent species
persisting through this period of extreme habitat bottleneck, reduces
the chance of flooding, and lowers the risk of mega-fires. Saving mature
forests that are effectively emergent OG contributes significantly to
these goals in the short run, and will be essential in the long run..

Sincerely,

David A. Perry

Professor (emeritus)

Department of Forest Science

Oregon State University

[Literature Cited]{.underline}:

Amaranthus, M.P., J.M. Trappe, L. Bednar, and D. Arthur. 1994. Hypogeous
fungal production in mature Douglas-fir forest fragments and surrounding
plantations and its relation to coarse woody debris and animal
mycophagy. Canadian Journal of Forest Resources. 24(11): 2157-2165.

Frest, T.J, and E.J. Johannes. 1993. Mollusc species of special concern
within the the range of the northern spotted owl. Final Report. Prepared
for the Forest Ecosystem Management Assessment Team. USDA Forest
Service. Portland, Oregon.

Kareiva, P., and U. Wennergren 1995. Connecting landscape patterns to
ecosystem and population processes. Nature. 373: 299-302.

Jones, J. A. and D.A. Post, 2004. Seasonal and successional streamflow
response to forest cutting and regrowth in the northwest and eastern
United States. WATER RESOURCES RESEARCH, VOL. 40, 5203

Noss, R.F. amnd A.Y. Cooperrider. 1994. Saving Nature's Legacy. Island
Press.

NRC. 2000. Environmental Issues in Pacific Northwest Forest Management.
National Academy Press. Washington, D.C.

. SPIES, T.A., MILES A. HEMSTROM, ANDREW YOUNGBLOOD, SUSAN HUMMEL (2006)
Conserving Old-Growth Forest Diversity in Disturbance-Prone Landscapes\
Conservation Biology 20 (2) , 351--362

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Tappeiner, J.C., D. Huffman, D. Marshall, T.A. Spies, J.D. Bailey. 1997.
Density, ages, and growth rates in old-growth and young-growth forests
in coastal Oregon. Canadian Journal of Forest Resources. 27: 638-648.

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[^1]: "Adequate" may vary widely depending on specific circumstances and
    must be determined on a case-by-case basis. For example, the amount
    of area needed in strictly protected status depends on what is done
    in the matrix.