Conifer Mortality Estimates Using Conifer Mortality Estimates Using Forest Inventory and Analysis’s Annual Forest Inventory and Analysis’s Annual

Inventory SystemInventory System

Michael T. ThompsonForest Inventory and Analysis

Interior West RegionUser Group Meeting

April 13, 2010

FIA’s Annual Inventory DesignFIA’s Annual Inventory Design

Federal legislation passed in 1998 dictated major changes to the FIA program.

Annual inventories in all states.

Annual inventory premise was a tradeoff between temporal currency and statistical reliability.

Panel – one of 5 to 10 interpenetrating groups.

The western regions are on a 10-year cycle where one panel of data represents 10 percent of all plots.

The Panel SystemThe Panel System

Hexagons of equal area are used to establish plot locations.

Each hexagon represents an area of about 6,000 acres.

The hexagons completely cover the conterminous 48 states.

The Annual Inventory

Each year/panel is a spatially unbiased Each year/panel is a spatially unbiased grid of plots that can provide a stand-grid of plots that can provide a stand-alone inventory estimate. The stand-alone alone inventory estimate. The stand-alone may be referred to a the independent may be referred to a the independent panel designpanel design

Mortality Tree

For inventories with no re-measurable previous inventory a mortality tree is defined as any standing dead tree 5.0-inches d.b.h./d.r.c. and larger that was alive within the past five years but has died. The attribute of interest for a mortality tree (volume, basal area, etc.) is usually expressed as an annual average over a five year interval. A general cause of death (i.e. insects) is assigned to all trees classified as mortality.

Can annual inventory mortality estimates enhance estimates from

aerial detection surveys?

Average annual number of lodgepole pine mortality trees 5.0-inches and larger killed by insects in Colorado by mortality period, 2002 - 2009

-10

0

10

20

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50

60

1997-2002 1998-2003 1999-2004 2000-2005 2001-2006 2002-2007 2003-2008 2004-2009

Nu

mb

er o

f tre

es (

mill

ion

s)

Mortality periodError bars represent the 95 percent confidence interval

Statistical AnalysisCharts Display confidence intervals.

Panel EffectNonparametric test (Wilcoxon) Pr > Chi-Square < .0001ANOVA Pr > F <.0001

Compare Individual PanelsTest all combinations of individual panels against each other (Bonferroni multiple test correction factor )

(2004 – 2009)/(2002-2007)*** significant at 0.05 level(2004--2009)/(2001-2006)*** significant at 0.05 level(2004 – 2009)/(1999-2004)*** significant at 0.05 level(2004 – 2009)/(2000-2005)*** significant at 0.05 level(2004 – 2009)/(1997-2002)*** significant at 0.05 level(2004 – 2009)/(1998-2003)*** significant at 0.05 level(2003 – 2008)/(1998-2003)*** significant at 0.05 level

Statistical Analysis – cont.Regression Analysis

Label Parameter Standard Error t value Pr > |t|

Intercept -415.15 64.43357 -6.44 <.0001Mortality period .20726 .03213 6.45 <.0001

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50

60

1997-2002 1998-2003 1999-2004 2000-2005 2001-2006 2002-2007 2003-2008 2004-2009

Nu

mb

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f tre

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mill

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s)

Mortality periodError bars represent the 95 percent confidence interval

Number of live lodgepole pine trees 5.0-inches d.b.h. and larger with evidence of bark beetle damage in Colorado by

measurement year, 2002 - 2009

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0

20

40

60

80

100

120

2002 2003 2004 2005 2006 2007 2008 2009

Mill

ion

tree

s

Measurement yearError bars represent the 95 percent confidence interval

Number of live lodgepole pine trees >= 5.0-inches d.b.h. in Colorado by measurement year, 2002 - 2009

0

100

200

300

400

500

600

700

800

900

2002 2003 2004 2005 2006 2007 2008 2009

Mill

ion

tree

s

Measurement yearError bars represent the 95 percent confidence interval

0

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300

350

2 4 6 8 10 12 14 16 18+

Mill

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tree

s

2-inch Diameter Class

Number of live lodgepole pine trees in Colorado by diameter class, 2009

Number of live lodgepole pine trees >= 10.0-inches d.b.h. in Colorado by measurement year, 2002 - 2009

0

50

100

150

200

250

2002 2003 2004 2005 2006 2007 2008 2009

Mill

ion

tree

s

Measurement year

Average annual number of subalpine fir mortality trees 5.0-inches and larger in Colorado by mortality period, 2002 - 2009

0

2

4

6

8

10

12

14

16

18

20

1997-2002 1998-2003 1999-2004 2000-2005 2001-2006 2002-2007 2003-2008 2004-2009

Mill

ion

tree

s

Mortality Period

Number of live subalpine fir trees >= 10.0-inches d.b.h. in Colorado by measurement year, 2002 - 2009

0

20

40

60

80

100

120

140

160

2002 2003 2004 2005 2006 2007 2008 2009

Mill

ion

tree

s

Measurement Year

Average annual number of lodgepole pine mortality trees 5.0-inches and larger in Montana by mortality period, 2002 - 2009

0

10

20

30

40

50

60

1998-2003 1999-2004 2000-2005 2001-2006 2002-2007 2003-2008 2004-2009

Mill

ion

tree

s

Mortality Period

Number of live lodgepole pine trees >= 10.0-inches d.b.h. in Montana by measurement year, 2002 - 2009

0

50

100

150

200

250

300

2003 2004 2005 2006 2007 2008 2009

Mill

ion

tree

s

Measurement Year

Average annual number of lodgepole pine mortality trees 5.0-inches and larger in Idaho by mortality period, 2002 - 2009

0

5

10

15

20

25

30

35

40

45

50

1999-2004 2000-2005 2001-2006 2002-2007 2003-2008 2004-2009

Mill

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tree

s

Mortality Period

Remeasurement of Previously Established Plots

Variable-radius Plots

Montana

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60

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100

120

Initial Inventory Survivor Growth

Ingrowth Mortality Removals Terminal Inventory

Bas

al a

rea

per

acr

e (s

q. f

t.)

Relationship between initial conifer inventory, terminal conifer inventory, and conifer components of change on NFS forest land in

Montana

1990’s

2000’s

Relationship between initial conifer inventory, terminal conifer inventory, and conifer components of change on non-NFS forest land in

Montana

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20

40

60

80

100

120

Initial Inventory Survivor Growth Ingrowth Mortality Removals Terminal Inventory

Bas

al a

rea

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acr

e (s

q. f

t.)

Relationship between initial lodgepole pine inventory, terminal lodgepole pine inventory, and lodgepole pine components of change on

NFS forest land in Montana

0

5

10

15

20

25

30

Initial Inventory Survivior Growth Ingrowth Mortality Removals Terminal Inventory

Bas

al a

rea

per

acr

e (s

q. f

t.)

Relationship between initial whitebark pine inventory, terminal whitebark pine inventory, and whitebark pine components of change on

NFS forest land in Montana

0

1

2

3

4

5

6

7

Initial Inventory Survivor Growth Ingrowth Mortality Removals Terminal Inventory

Bas

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acr

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q. f

t.)

ConclusionConclusion

Lodgepole pine is experiencing extremely high levels of mortality in Colorado—primarily due to MPB epidemic.

Inventories of large-diameter lodgepole pines in Colorado are declining at an unusually rapid rate.

Initial results from annual inventories appear promising for evaluating trends in levels of tree mortality.

The power to detect significant events related to mortality and other parameters of interest will increase substantially with estimates derived from the remeasured (paired) plots that will eventually be available region-wide.