variable retention harvest

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Mezger To: Kim Titus, Salem District Manager From: Tracy Mezger Date: May 30, 2014 Subject: Decision of variable retention harvest Description of the action and prescription A variable retention harvest is the best method to create diverse early seral ecosystems while providing viable timber and revenue. A variable retention harvest is the best method for restoring forest structures by emulating a natural disturbance. Disturbances are important for the forest by allowing regeneration and developing complex forest structures. They are also key for creating early seral conditions. Maintaining forest structures can help 1

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Page 1: Variable Retention Harvest

Mezger

To: Kim Titus, Salem District Manager

From: Tracy Mezger

Date: May 30, 2014

Subject: Decision of variable retention harvest

Description of the action and prescription

A variable retention harvest is the best method to create diverse early seral ecosystems

while providing viable timber and revenue. A variable retention harvest is the best method for

restoring forest structures by emulating a natural disturbance. Disturbances are important for the

forest by allowing regeneration and developing complex forest structures. They are also key for

creating early seral conditions. Maintaining forest structures can help meet the demands of

habitat opportunity through ecological and structural diversity. Ecological and structural

diversity can be established

by retaining legacies and

course woody debris on the

harvest site and replanting

after the harvest. Replanting

the areas also allows for

profitable regeneration for

future harvests. Creating

structural diversity can be

created either through Figure 1: Variable Retention Harvest (Johnson, 2014)

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Mezger

aggregated retention or dispersed retention, leaving at least 25% of the stand remaining. The

legacy trees are left until the next harvest rotation. Both surviving and dead trees offer habitat

with cavities and stumps that help maintain species diversity. A variable retention harvest will

also avoid building logging roads by primarily utilizing skyline extraction of the harvested

timber, which decreases erosion and sedimentation. A visual of what a variable retention harvest

looks like is shown above as Figure 1.

Landscape context

The project area for this harvest lies on Bureau of

Land Management (BLM) forested land in the Salem

District. It is also part of Mary's Peak resource area, an area

abundant with natural resources. Mary's Peak is the highest

point in Oregon's Coast Range reaching 4,097 ft. The Salem

district lies northwest in Oregon, highlighted in Figure 2.

The specific harvest area in Mary's Peak resource area is

dominated by young conifers of about 60 years of Figure 2: Salem District (BLM, 2014)

age with little structural complexity and diversity. The Mary's Peak resource area also retains

late successional forest stands, which adds complexity to the area's overall structure. It is also an

area managed for riparian reserves and critical habitat to the endangered Marbled Murrelets,

Coho Salmon, and Northern Spotted owl (Wimberly, 2002). The critical habitat of these species

range throughout the Pacific Northwest (Johnson, 2014). Our proposed harvest area is not

located in critical habitat.

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Reason for the action

The variable retention harvest method meets the goals of the Northwest Forest Plan

(NWFP) and the goals of the O&C Act. The NWFP helps to guide forest practices towards

sustainability. The NWFP also aims to integrate agencies in an effort to make better decisions

regarding long term forest management.The plan was established not only to sustain timber

supplies in the Northwest, but to protect fish and wildlife habitat for those federal forests. The

O&C Act was created to provide a permanent forest production to help local economic stability

while protecting and regulating watersheds (USDI BLM, n.d.(b)).

The chosen action of variable retention harvest balances the societal need for economic

stability and the biological need for ecosystem services to the forest structure. The NWFP and

the O&C Act have similar goals for the management of federal forests in the Northwest. A major

reason the NWFP was implemented was to protect endangered species. The Mary's Peak

resource area contains portions of critical habitat for murrelets, salmon, and the spotted owl; this

method of harvest helps retain a buffer zone that meets the goals for protecting endangered

species who rely on ecologic functions under the NWFP. Revenue from the timber will help

O&C counties' economies which is a priority of the act (USDI BLM, n.d.(b)).

Under the 1937 O&C Act, this BLM land is to be managed for sustained permanent

forest production (USDI BLM, n.d.(a)). As a moist forest type, the Mary's Peak Resource Area

rarely experiences wildfire; historically only experiencing a severe fire every 100 to 200 years

(Spies, et. al., 2007). When wildfires occur today, they are often suppressed, adding to a major

decline of early seral habitat from the historical rate of 16% to the current 3% in the Oregon

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Coast Range. This means a decrease in habitat for species who are specialized for early seral

ecosystem structures and a decrease in biodiversity. The open space after a severe disturbance

offers new conditions for rapid growth with little competition; this rapid growth is shown in

Figure 3. This phase of forest structure is also the only time when conifers and overstory cover

does not dominate the site. The variable retention harvest method replicates a natural event like

wildfire in an area that lacks this type of stand diversity and species complexity. Immediate

growth in these areas offer future conditions for sustainable harvest. This form of ecological

forestry helps to maintain ecosystem services for species as well as a profitable yield of timber.

The estimated revenue generated from the variable retention harvest at this site is

calculated below. The total harvest volume is calculated to be: 60,000*.75*91= 4,095,000 board

ft; the total stumpage value comes out at : 4,050*$300= $1,215,000. This revenue is important

for O&C land

revenue to

compensate

counties. This will

help stabilize local

economies.

Figure 3: Early seral rapid growth(Johnson, 2014).

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Other effects

Positive effects may reach farther than providing habitat for specialized species and

healthier forest regeneration. Variable retention harvest can also be positively impacting complex

food webs across the entire forest. By emulating a natural disturbance that is spatially variable,

we are encouraging historical conditions that makes the forest most efficient. People can also

benefit from this system by incorporating ecosystem values into their management; timber

production is reliable and adaptive.

Negative affects are still present as the land is still manipulated by humans. Although

management incorporates the entire system, some consequences may not be accounted for. This

stand is only 20 years away from becoming old growth. Cutting the stand takes away the

opportunity for future Northern Spotted owl habitat. As atmospheric changes like climate

change, this stand will contribute less than it could have for carbon sequestration once it is

harvested. Other problems like invasive species pose a threat to specialized species relying on

certain climate and habitat conditions. This may lead to further protection of forest areas

stopping timber harvest which can lead to economic deficiency.

Compliance with the Endangered Species Act

The Endangered Species Act (ESA) lists a species as endangered if it is at risk of

extinction in a portion or all of its range. The purpose of the ESA is to protect and recover listed

species and the ecosystems they depend on (Brown & Shogren, 1998). The ESA ustilizes legal

tools to assess whether and action may result in a taking and will consult the organizer about

alternatives. This area is not in critical habitat range, as shown in Figure 4 and 5, and a variable

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retention harvest will not conflict with the ESA and will not result in a taking of endangered

species. Although the harvest area is not critical habitat now, it has the potential to become old

growth in a short time which could contribute to the recovery of these species through added

habitat. Addition features of ecological forestry does not conflict with landscape conditions

endangered species may rely on. For example, buffering riparian zones with old growth ensures

riparian health and water quality through provided shade microclimate and reduced

sedimentation from erosion. Limited matrix gaps and connectivity of legacy trees ensures that

species can move across the harvest without leaving a moderately complex forest structure

(MacDonald, et. al., 2003).

Fig. 4 (above left): Critical habitat of N. Spotted Owl Fig. 5 (above right): Critical habitat of C. Salmon

and M. Murrelet (Johnson, 2014). (Johnson, 2014).

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Keys to increase public acceptability

The public feels very strongly against clearcutting on federal lands. Opposition is socially

constructed based on values and normative science, which is essentially advocacy for a

particular view (Bliss, 2000). People should understand that variable retention is different from

clear cutting as it retains part of the forest structure that is essential for diversity and stand

complexity; ecological concerns are addressed and managed for. This prescription also allows

for early seral ecosystems, whereas clear cutting usually skips this phase by spraying herbicides

on the area where shrubs and hardwoods might grow. Education is key here. Misleading science,

has confused the public.

This type of harvest method accommodates to people's values by supporting biodiversity,

which is easier to relate to people than the science behind harvest methods. The public needs to

not only understand the difference between harvesting methods but be able to see the difference,

which is more personal and valuable. There are similar features between variable retention and

clear cuts that may be confusing so showing people the difference may be a positive approach to

education. Socially, people are still going to be concerned about harvesting timber on federal

lands because the public is most interested in the aesthetic qualities and recreation. Informing the

public about harvests and of the opportunities to get involved in the decision making process

will help the acceptance of variable retention harvesting.

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References

Bliss, J. 2000. Public perceptions of clearcutting. Journal of Forestry. 98(12), 4-9.

Brown, G. M., & Shogren, J. F. (1998). Economics of the Endangered Species Act. Journal of

Economic Perspectives, 12, 3-20.

Franklin, J.F., Mitchell, R.J., Palik, B.J.. 2007. Natural disturbance and stand development.

USDA Forest Service General Tech, 19, 1-2.

Johnson, N. May 22, 2014. Variable retention harvest/ early seral. FOR 460 class. Lecture

conducted from Corvallis, Oregon.

Macdonald, J. S., MacIsaac, E. A., & Herunter, H. E. (2003). The effect of variable-retention

riparian buffer zones on water temperatures in small headwater streams in sub-boreal

forest ecosystems of British Columbia.Canadian Journal of Forest Research, 33(8),

1371-1382.

Spies, T.A., Johnson, K.N., Burnett, K., Ohmann, J.L., McComb, B.C, Reeves, G.H., Bettinger,

P., Kline, J.D., & Garber-Yonts, B. 2007. Cumulative ecological and socioeconomic

effects of forest policies In Coastal Oregon. Ecological Applications 88(1): p. 5-17.

Swanson, M. J., F. Franklin, R. L Beschta, C. M. Crisafulli, D. A. DellaSala, R. L. Hutto, D.

B. Lindenmayer, and F. J. Swanson. 2011. The forgotten stage of forest succession: early

successional ecosystems on forest sites. Frontiers in Ecology Environment. 9:117–125.

USDI BLM. No date (a). O&C Sustained Yield Act. The land, the law, and the legacy: 1937-

1987. http://www.blm.gov/or/files/OC_History.pdf

USDI BLM. No date (b). Overview of the Oregon and California (O&C) Lands Act of 1937.

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http://www.blm.gov/or/rac/files/Oregon%20Flyer.pdf

Wimberly, M. 2002. Spatial simulation of historical landscape patterns in coastal forests of the

Pacific Northwest. Can. J. For. Res. 32:1316-1328.

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