Introduction to

Dendrochronologyand

San Juan Fire Histories

Introduction to

Dendrochronologyand

San Juan Fire Histories

DendrochronologyDendrochronology

Dendron = Tree

Chronos = Time

Logos = Study of

Dendron = Tree

Chronos = Time

Logos = Study of

Building a master chronology

Principles of

Dendrochronology

Principles of

Dendrochronology•Uniformity

•Limiting Factors

•Sensitivity•Ecological Amplitude

•Site Selection

•Crossdating

•Uniformity

•Limiting Factors

•Sensitivity•Ecological Amplitude

•Site Selection

•Crossdating

Principle of UniformityPrinciple of UniformityPrinciple of UniformityPrinciple of Uniformity

““The present is the key to the past.”The present is the key to the past.”

~James Hutton, 1785~James Hutton, 1785

““The past is the key to the future.”The past is the key to the future.”

~Dendro quote ~Dendro quote

““The present is the key to the past.”The present is the key to the past.”

~James Hutton, 1785~James Hutton, 1785

““The past is the key to the future.”The past is the key to the future.”

~Dendro quote ~Dendro quote

1726-17971726-1797James HuttonJames Hutton1726-17971726-1797James HuttonJames Hutton

Principle of Limiting Factors

Principle of Limiting Factors

Principle of Ecological Amplitude

Principle of Ecological Amplitude

Principle of Site SelectionPrinciple of Site Selection

Principle of CrossdatingPrinciple of Crossdating

Principle of Crossdating

18991899

19021902

19041904

18961896

18931893 18941894

San Juan Fire HistoriesSan Juan Fire Histories

Recorder Recorder TreesTreesRecorder Recorder TreesTrees

Jackson MtnJackson Mtn

JAK5JAK5

JAK3JAK3

JAK1JAK2JAK1JAK2

JAK4JAK4

Archuleta MesaArchuleta Mesa

L A R G E F I R E S

M E D I U M F I R E S

FFIREIRE H HISTORYISTORY P PLOTLOT

A Brief History….A Brief History….

Aristotle350 BC

Aristotle350 BC

da Vinci1500

da Vinci1500

Duhamel & Buffan1737

Duhamel & Buffan1737

Alexander Twining1827

Alexander Twining1827

Charles Babbage1838

Charles Babbage1838

Theodor Hartig1855

Theodor Hartig1855

Jacob Keuchler1859

Jacob Keuchler1859

Principle of Aggregate Tree Growth

Principle of Aggregate Tree Growth

Rt = Ring GrowthGt = Age related growth curveCt = Climate related growth variation & trendD1t = Endogenous disturbance pulseD2t = Exogenous disturbance pulseEt = Random variation

Rt = Ring GrowthGt = Age related growth curveCt = Climate related growth variation & trendD1t = Endogenous disturbance pulseD2t = Exogenous disturbance pulseEt = Random variation

Principle of ReplicationPrinciple of Replication

Fire scar formationFire scar formation

Piedra AreaPiedra Area

Sheep CreekSheep Creek

Fire History LocationsFire History Locations

AllFires

Site Period MFI Range

Archuleta MesaDry Ponderosa Pine

1650 – 1900 10 2 – 24

Turkey SpringsPonderosa Pine

1700 – 1880 6 1 – 18

Bear ParkWarm-Dry Mixed Conifer

1685 – 1880 8 1 – 31

Jackson MtnCool-Moist Mixed Conifer

1685 – 1873 10 2 – 25

Corral MtnCold-Wet Mixed Conifer

1685 – 1851 18 3 – 45

25%Scarre

d

Site Period MFI Range

Archuleta MesaDry Ponderosa Pine

1650 – 1900 17 7 – 40

Turkey SpringsPonderosa Pine

1700 – 1880 18 10 – 33

Bear ParkWarm-Dry Mixed

Conifer1685 – 1880 22 9 – 71

Jackson MtnCool-Moist Mixed Conifer

1685 – 1873 21 10 – 65

Corral MtnCold-Wet Mixed Conifer

1685 – 1851 42 24 – 65