Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted...

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Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests

Transcript of Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted...

Page 1: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

Over 80 yearsLate-successional

Old-growth

Raymond DavisMonitoring Lead

Older Forests and Spotted Owls(Northwest Forest Plan Area)

Defining Older Forests

Page 2: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

• Early 1900s – Relative terms like “old-growth, large second growth, and second growth”. Differentiated slower growing older forests from the faster growing younger forests. A general sense of stand age, but largely based on diameter at breast height (DBH) of the largest dominant and co-dominant live trees.

• 1980s – Old-growth is best perceived as, “a stage of forest development characterized by more diversity of structure and function than that found in younger successional stages.”

• Chief’s Memo (1989) – Old-growth is usually distinguished by the presence of larger, older trees and structural attributes such as multiple canopy layers, decadence in the form of standing dead trees (snags), and accumulations of fallen trees (down wood).

• Interim Definitions (1992, 1993) - Provided discrete classifications based on minimum amounts of old-growth elements such as snags and logs. Related these things to stand age (usu. 150 to 240 years).

Defining Older Forests - History

Page 3: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

• FEMAT and the Northwest Forest Plan (1993) – Mature phase of stand development begins around 80 years and is characterized by relatively large live and dead trees, although multiple canopy layers may not yet be well developed. • Maturation stage = 80-140yr• Transition stage = 150-250yr

• Franklin and Johnson (2013) – Used three different stand ages that might be declared “old” – 80, 120, and 160 years. Part of the social dialogue and intensely debated.

• BLM Western Oregon Plan Revision (2015) – Older (mature) and more structurally complex multi-layered conifer forests (80, 120, 140, 160, and 200 years).

Defining Older Forests - History

Page 4: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

Refine Definition for Older Forests

Page 24 Existing definitions provided black and white answers, while in the real world structure and composition differ in gradients.

Page 31 Need refined definitions or Need refined definitions or indicesindices to assign plots and remotely sensed stands to a position along a continuum of older forest structure and composition.

Page 5: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

Previous Monitoring Definition

+CanopyCover≥10%

Too simple and hard to interpret change

AverageDBH ≥20in

Page 6: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

Old-Growth Forest Structure Elements

+ + +

Largelive trees

Snags Down wood

Diameterdiversity

“New” Monitoring Definition

Page 7: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

Old

-Gro

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Spies and Franklin. 1988. Old growth and forest dynamics in the Douglas-fir region of western Oregon and Washington. Natural Areas Journal. 8: 190-201.

Page 8: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

Old

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Back to the Basic Elements

Page 9: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

La

rge

live

tre

e d

en

sity

Stand ageyounger older

100

0

Large Trees

Page 10: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

La

rge

live

tre

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Stand ageyounger older

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Large Trees

plot data

Page 11: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

Sn

ag

de

nsi

ty

Stand ageyounger older

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Large Snags

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De

ad

wo

od

co

ver

Stand ageyounger older

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Fallen Trees

Page 13: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

Dia

me

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div

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ity in

de

x

Stand ageyounger older

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Multiple Canopy Layers

Page 14: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

Old

-Gro

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Average Score of all Elements

Page 15: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

Old

-Gro

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Selecting Mapping Thresholds

Page 16: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

Old

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Selecting Mapping Thresholds

Page 17: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

Assigned plots and remotely sensed data to a positionalong a continuum of old forest structure and composition

Older forests on federally managed lands in 1993

Page 19: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

Scatter Graph of Western Hemlock PlotsOGSI vs Stand Age

Page 20: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

Scatter Graph of Western Hemlock PlotsOGSI vs Stand Age

<80yr withhigh OGSI

Page 21: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

Scatter Graph of Western Hemlock PlotsOGSI vs Stand Age

<80yr withhigh OGSI

>80yr withlow OGSI

Page 22: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

25th

75th

5th

50th

95th

Stand Age

OG

SI

Percentiles Graph of Western Hemlock PlotsOGSI vs Stand Age

Page 23: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

25th

75th

5th

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Stand Age

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Percentiles Graph of Western Hemlock PlotsOGSI vs Stand Age

Page 24: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

25th

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Percentiles Graph of Western Hemlock PlotsOGSI vs Stand Age

Page 25: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

Stand Age

OG

SIWestern Hemlock

OGSI Elements vs Stand Age

80 yr80 yr 200 yr200 yr

Page 26: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

Stand Age

OG

SI

Grand Fir-White FirOGSI Elements vs Stand Age

80 yr80 yr 200 yr200 yr

Page 27: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

Stand Age

Pro

po

rtio

n o

f O

GS

IWestern Hemlock

OGSI Element Proportion vs Stand Age

80 yr80 yr 200 yr200 yr

Page 28: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

Grand Fir-White FirOGSI Element Proportion vs Stand Age

Stand Age

OG

SI

80 yr80 yr 200 yr200 yr

Page 29: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

WillametteWillametteValleyValley

UmpquaUmpquaValleyValley

Page 30: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

WillametteWillametteValleyValley

UmpquaUmpquaValleyValley

Page 31: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

Monitoring the Continuum

Page 32: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

Acknowledgements

Janet L. Ohmann, Robert E. Kennedy, Warren B. Cohen, Matthew J. Gregory, Zhiqiang Yang, Heather M. Roberts, Andrew N. Gray, and Thomas A. Spies

o Justin Braaten (OSU)o Daniel Donato (WA DNR)o Andrew Merschel (OSU)o Vicente Monleon (USFS PNW)o Rob Pabst (OSU)o Matt Reilly (OSU)o Mike Simpson (USFS)o Andrew Yost (ODF)o Harold Zald (OSU)o Miles Hemstrom (INR)o Ashley Steele (USFS PNW)o Becky Gravenmier (USFS PNW)

Page 33: Over 80 years Late-successional Old-growth Raymond Davis Monitoring Lead Older Forests and Spotted Owls (Northwest Forest Plan Area) Defining Older Forests.

Questions?