Scott Anderson 2-2-06 - NPS

Contrasting Vegetation and Fire Histories on the Point Reyes Peninsula

During the Pre-Settlement and Settlement Periods

R. SCOTT ANDERSONEnvironmental & Quaternary Sciences

Northern Arizona UniversityFlagstaff, Arizona

Primary Collaborator:Peter Brown (RMTRR)

Supported by:National Park Service

(Point Reyes National Seashore)

Outline of Talk

• Introduction to Paleoecological Research• Physical Setting of the Study Sites• Vegetation & Fire Histories

– Previous Research– Present Research

• Comparison with Other Sites along Coastal California

• General Considerations & Conclusions

How do paleoecologists collect data?

Obtain Sediment Cores from Lakes, Bogs, Wetlands

Isolate Pollen, Plant Macrofossils & Charcoal

Compare Fossil Datasets to Modern Datasets

Sediment Coring – Lakes & Bogs

“Tools” of the Paleoecologist

“Tools” of the Paleoecologist: Pollen Macrofossils

http://www.geo.arizona.edu/palynology/geos462/29charcoal.html

http://nrg.ncl.ac.uk/people/staff/tyson/gallery/gal11.html

“Tools” of the Paleoecologist:Charcoal Particles

Microscopic Charcoal

Macroscopic Charcoal

Charcoal Production & Transport

Production

Transport

Deposition

+

Production & Transport, Clockwise from upper left: http://www.atmos.umd.edu/~zli/Info/crown_fire-copy%20copy.jpg; http://www.fs.fed.us/rm/hayman_fire/text/03romme/03_fig11.html; http://www.wapa.gov/media/cct/sept6/images/hayman4.jpg; http://www.kwphoto.com/Resources/Images/94_0007-20.jpg

Limitations of Paleoecology

• Not all species are preserved as fossils• Not all body parts are preserved as fossils

Biocoenosis (life assemblage)

versus

Thanatocoenosis (death assemblage)

How do we age the sediments?Radiometric dating

14C = range up to 40,000 years ago210Pb = range up to 150 years ago

137Cs = 1964 AD peak in bomb testing

Comparison with known historical events

Comparison with known fires

History of Settlement & Use of Pollen for Dating

1817 - Spanish influence commenced here by establishment of San Rafael Franciscan mission (Brown et al.1999)

After 1821 - Point Reyes opened to land claims, with the first granted in 1836 in the Olema Valley

The area was subsequently opened for grazing and dairy ranching (Livingston 1994, 1995)

The settlement period identified by increases in pollen indicators of grazing and land disturbance (i.e., dock [Rumex], plantain [Plantago], filaree[Erodium]), planted trees (Eucalyptus)

Paleoecological Research at PORE –3 Previous Studies

• Rypins et al. 1989 - Coast Trail Pond plus stratigraphic sections

– 12,300 14C-yr record, begins w/ Douglas-fir – fir forest– 10,300 to 9,400 14C yr ago transition to coastal sage scrub and

grassland • Russell 1983 - Wildcat Lake

– 900 yr record (?)– Suggested alternation of importance of grassland and sage

scrub vegetation– Charcoal concentration less above ca. 35 cm depth (age?)

• Duncan 1992 - Mud Pond– 1000 yr record– vegetation and ethnobotanical uses of plants by the Miwok at the

time of European contact

Terminology(Ages Approximate)

• Late Pleistocene = prior to 11,500 years ago

• Holocene = since 11,500 years ago– Early Holocene = to 7000 years ago– Middle Holocene = 7000 to 4500 years ago– Late Holocene = 4500 years ago to 1850 AD– Settlement Period = after 1850 AD

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45000500005500060000

65000

Age

200

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1000

Dep

th

20 40

CYPRESS Family

100 200 300 400

PINE (a

ll typ

es)

20

DOUGLAS-FIRFIR

20 40 60

SEQUOIA

OAKTANOAKALD

ER

20

COYOTE BRUSH &

Othe

rsLaguna de las Trancas (near Santa Cruz)

The Last 65,000 Years Along the Coast

Studies Sites on Point Reyes

• Coast Trail Pond• Glenmire

• Creamery Bay Bog• Wildcat Lake

• Shutter Ridge Pond

Why Choose These Sites?

• Examined a variety of wet areas• Chose Sites from:

–Range of vegetation types–Over an elevational gradient

Coast Trail Pond• 230 m above sea

level• Coastal scrub near

closed forest• Little historical data

exists on the history of grazing at this site

• Oldest site in our study

Coast Trail Pond

0

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300

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500

Dep

th c

m

10002000300040005000600070008000

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1300014000150001600017000

Age

Cal

yr B

P

12260 ±110

9040 ± 40

7100 ± 50

1850 AD

1963 AD

Dat

es

20

FIR

20 40

PiINE

20

DOUGLAS-FIR

SEQUOIA20

ALDEROAK

20

SAGEBRUSH

20

Other Sage S

crub Taxa

20 40 60

COYOTE BRUSH &

Oth

ers

20406080

GRASS

204060

SEDGE

20

WATER FERNFILAREEEUCALYPTUS

GOOSEFOOT

20

DOCKPLANTAINSPORORMIELLA

Coast Trail Pond - Trees, Shrubs, Herbs, Wetland

Forest and Sage Scrub

0

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200

300

400

500

Dep

th c

m

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1300014000150001600017000

Age

Cal

yr B

P

12260 ±110

9040 ± 40

7100 ± 50

1850 AD

1963 AD

Dat

es

20

FIR

20 40

PiINE

20

DOUGLAS-FIR

SEQUOIA20

ALDEROAK

20

SAGEBRUSH

20

Other Sage S

crub Taxa

20 40 60

COYOTE BRUSH &

Oth

ers

20406080

GRASS

204060

SEDGE

20


GOOSEFOOT

20



Sage Scrub w/ Forest – Driest

Period

0

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300

400

500

Dep

th c

m

10002000300040005000600070008000

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1300014000150001600017000

Age

Cal

yr B

P

12260 ±110

9040 ± 40

7100 ± 50

1850 AD

1963 AD

Dat

es

20

FIR

20 40

PiINE

20

DOUGLAS-FIR

SEQUOIA20

ALDEROAK

20

SAGEBRUSH

20

Other Sage S

crub Taxa

20 40 60

COYOTE BRUSH &

Oth

ers

20406080

GRASS

204060

SEDGE

20


GOOSEFOOT

20



Sage Scrub w/ Mixed Hdwds &

Conifers

0

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300

400

500

Dep

th c

m

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11000

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1300014000150001600017000

Age

Cal

yr B

P

12260 ±110

9040 ± 40

7100 ± 50

1850 AD

1963 AD

Dat

es

20

FIR

20 40

PiINE

20

DOUGLAS-FIR

SEQUOIA20

ALDEROAK

20

SAGEBRUSH

20

Other Sage S

crub Taxa

20 40 60

COYOTE BRUSH &

Oth

ers

20406080

GRASS

204060

SEDGE

20


GOOSEFOOT

20



Historic Period

Glenmire• 167 m above sea level• Wetland NW of Glen

Campground• Closed Douglas-fir forest

with California bay and oak

• Part of the Shafter Ranches, South End Tract (Livingston 1994). By 1879 a thriving dairy farm

• Cored in 30 cm of water

Glenmire

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th c

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Age

Cal

yr B

P

5410 ±110

1650 ±40

1710 ±40

1240 ±40

1880 AD

Dat

es

FIR

20

PINE

20

DOUGLAS-FIR

20

SEQUOIA20

ALDERTANBARK O

AK

20

OAK

2040

COYOTE BRUSH &

Oth

ers

20

SAGEBRUSH

20

Other Sag

e Scr

ub Tax

a

20406080

GRASS

50100150

SEDGE

20

GOOSEFOOT

FILAREE

50 100150

DOCKPLANTAINEUCALYPTU

S

Glenmire - Trees, Shrubs, Herbs, Wetland

Pond Dry

0

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Dep

th c

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Age

Cal

yr B

P

5410 ±110

1650 ±40

1710 ±40

1240 ±40

1880 AD

Dat

es

FIR

20

PINE

20

DOUGLAS-FIR

20

SEQUOIA20

ALDERTANBARK O

AK

20

OAK

2040

COYOTE BRUSH &

Oth

ers

20

SAGEBRUSH

20

Other Sag

e Scr

ub Tax

a

20406080

GRASS

50100150

SEDGE

20

GOOSEFOOT

FILAREE

50 100150


S


Mixed Conifer and Hardwood Forest

w/ Sage Scrub

0

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Dep

th c

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Age

Cal

yr B

P

5410 ±110

1650 ±40

1710 ±40

1240 ±40

1880 AD

Dat

es

FIR

20

PINE

20

DOUGLAS-FIR

20

SEQUOIA20

ALDERTANBARK O

AK

20

OAK

2040

COYOTE BRUSH &

Oth

ers

20

SAGEBRUSH

20

Other Sag

e Scr

ub Tax

a

20406080

GRASS

50100150

SEDGE

20

GOOSEFOOT

FILAREE

50 100150


S


Historic Period

Creamery Bay Bog• 6 m above sea level• At the head of

Creamery Bay• Site of “K” Ranch

dairy farm• Oldest ranch site on

the Point (Livingston 1994)

• Presently the site is a wet meadow

Creamery Bay Bog

0

20

40

60

80

100

120

Dep

th c

m

0

100020003000400050006000700080009000

Age

yr C

al B

P

9010 ± 40

1840 AD

1902 AD1963 AD

Dat

es

20

PINE

DOUGLAS-FIR

SEQUOIAOAKALDERSAGEBRUSH

Other Sag

e Scr

ub Tax

a

204060

COYOTE BRUSH &

Oth

ers

20 40 60

GRASS

20 40 60

SEDGE

50100150200

FERNSWILLOW

20

QUILLWORT

20

DOCK

20

PLANTAIN

20

DANDILION &

Other

s

FILAREECORNEUCALYPTU

SCreamery Bay Bog - Trees, Shrubs, Herbs, Wetland

Grassland w/ ferns, herbs; site dry

0

20

40

60

80

100

120

Dep

th c

m

0

100020003000400050006000700080009000

Age

yr C

al B

P

9010 ± 40

1840 AD

1902 AD1963 AD

Dat

es

20

PINE

DOUGLAS-FIR


Other Sag

e Scr

ub Tax

a

204060

COYOTE BRUSH &

Oth

ers

20 40 60

GRASS

20 40 60

SEDGE

50100150200

FERNSWILLOW

20

QUILLWORT

20

DOCK

20

PLANTAIN

20

DANDILION &

Other

s



Grassland w/ Sage Scrub; some

Ponding?

0

20

40

60

80

100

120

Dep

th c

m

0

100020003000400050006000700080009000

Age

yr C

al B

P

9010 ± 40

1840 AD

1902 AD1963 AD

Dat

es

20

PINE

DOUGLAS-FIR


Other Sag

e Scr

ub Tax

a

204060

COYOTE BRUSH &

Oth

ers

20 40 60

GRASS

20 40 60

SEDGE

50100150200

FERNSWILLOW

20

QUILLWORT

20

DOCK

20

PLANTAIN

20

DANDILION &

Other

s



Historic Period

Wildcat Lake• 62 m above sea level• Sits on a complex

landslide deposit • Coastal scrub • Area NW of lake

(Wildcat Ranch) was occupied as early as 1858 (Livingston 1994)

• Cored in 8.75 m of water

Wildcat Lake

0

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1000

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Dep

th c

m

0500

100015002000

2500

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Age

Cal

yr B

P

3110 ±60

2000 ±40

1850 AD

Dat

es

20

PINE

20

DOUGLAS-FIR

2040

SEQUOIAOAK

20

SAGEBRUSH

Other Sag

e Scru

b Taxa

20

COYOTE BRUSH &

Others

20 40

GRASSSEDGECATTAIL

20

WATER-MILFOIL

2040 60

ALDER

50100150

SWEET GALE

20

WILLOW

50010001500

PEDIASTRUM

DOCKPLANTAIN

THISTLE

FILAREEEUCALYPTUS

Wildcat Lake - Trees, Shrubs, Herbs, Wetland

Pond Forms; Alder

0

100

200

300

400

500

600

700

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900

1000

1100

Dep

th c

m

0500

100015002000

2500

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Age

Cal

yr B

P

3110 ±60

2000 ±40

1850 AD

Dat

es

20

PINE

20

DOUGLAS-FIR

2040

SEQUOIAOAK

20

SAGEBRUSH

Other Sag

e Scru

b Taxa

20

COYOTE BRUSH &

Others

20 40

GRASSSEDGECATTAIL

20

WATER-MILFOIL

2040 60

ALDER

50100150

SWEET GALE

20

WILLOW

50010001500

PEDIASTRUM

DOCKPLANTAIN

THISTLE

FILAREEEUCALYPTUS


Coastal Sage Scrub w/ minor

Grassland & Mixed Forest

0

100

200

300

400

500

600

700

800

900

1000

1100

Dep

th c

m

0500

100015002000

2500

3000

Age

Cal

yr B

P

3110 ±60

2000 ±40

1850 AD

Dat

es

20

PINE

20

DOUGLAS-FIR

2040

SEQUOIAOAK

20

SAGEBRUSH

Other Sag

e Scru

b Taxa

20

COYOTE BRUSH &

Others

20 40

GRASSSEDGECATTAIL

20

WATER-MILFOIL

2040 60

ALDER

50100150

SWEET GALE

20

WILLOW

50010001500

PEDIASTRUM

DOCKPLANTAIN

THISTLE

FILAREEEUCALYPTUS


Historic Period

Shutter Ridge Pond• 35 m above sea level• In California annual

grassland• Situated on a push ridge• Site originally settled by

Garcia family• Probably became part of

Shafter’s “W” Ranch in the 1860’s (Livingston 1994)

• 1 m deep, but dries out

Shutter Ridge Pond

0

10

20

30

Dep

th c

m

0

400800

1200160020002400

Age

Cal

yr B

P

2780 ±40

1840 AD

Dat

es

20

PINE

DOUGLAS-FIR


CALIFORNIA-LILAC

20

COYOTE BRUSH &

Others

Coastal S

age Scru

b Taxa

20 40GRASS

20

SEDGE

20 40

QUILLWORTCATTAILDOCK

20

PLANTAINFILAREE

Shutter Ridge Pond - Trees, Shrubs, Herbs, Wetland

Grassland w/ Sage Scrub & Woodland

0

10

20

30

Dep

th c

m

0

400800

1200160020002400

Age

Cal

yr B

P

2780 ±40

1840 AD

Dat

es

20

PINE

DOUGLAS-FIR


CALIFORNIA-LILAC

20

COYOTE BRUSH &

Others

Coastal S

age Scru

b Taxa

20 40GRASS

20

SEDGE

20 40

QUILLWORTCATTAILDOCK

20

PLANTAINFILAREE

Shutter Ridge Pond - Trees, Shrubs, Herbs, Wetland

Historic Period

NO POLLEN PRESERVED

Coast Trail Pond

Shutter Ridge Pond

Creamery Bay Bog

Glenmire Wildcat Lake

Sage Scrub w/ Mixed

Conifers & Hardwoods

Sage Scrub w/ Mixed

Hardwoods

Open Hardwood Forest w/

Sage Scrub

Closed Coastal Conifer Forest

Grassland w/ Sage Scrub & Forest

Grassland w/ Sage Scrub

Grassland w/ Ferns,

Herbs

NO POLLEN PRESERVED

Mixed Conifer & Hardwood

Forest

Mxd Conifer – Hdwd, incrSage Scrub

Coastal Sage Scrub w/

Grassland and Minor

Mixed Forest

0

2

4

6

8

10

12

14

Cal Yr BP x 1000

0

2

4

6

8

10

12

14

Cal Yr BP x 1000

Higher Elevation

Lower Elevation

Alder

Historic Period –

Introduced Herbs

(Rumex, Erodium, Plantago) and Trees

(Eucalyptus)

(230 m asl)

(167 m asl)

(62 m asl)

(35 m asl)

(6 m asl)

Moist Dry

Solar Maximum in early Holocene

Kutzbach & Guetter 1986

Changes In SST

Herbert et al (2001)[also Barron et al 2003 & Lyle et al

(2001)]

CA Sea Surface Temp & δ18O

Barron et al. (2003)

Simulated Precipitation

for

Jan & July,

21K, 16K, 14K, 11K, 6K

& Present

Bartlein et al., 1998

Barron et al. (2003)

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Age

200

300

400

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600

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1000

Dep

th

20 40

CYPRESS Family

100 200 300 400

PINE (a

ll typ

es)

20

DOUGLAS-FIRFIR

20 40 60

SEQUOIA

OAKTANOAKALD

ER

20

COYOTE BRUSH &

Othe

rsLaguna de las Trancas (near Santa Cruz)

Anderson et al, unpublished

Northern Channel Islands & Inland

Empire

Southern California

Sites

Cañadade los

Sauces (SCI)

Soledad Pond (SRI)

Abalone Rocks Marsh

(SRI)

Mystic Lake (RiversideCo)

Dollar Lake

(SBCo)

Santa Rosae Island

Ingram & Kennett 1995

Modern Coastline

Pleistocene Coastline

Cañadade los

Sauces (SCI)

Mystic Lake (RiversideCo)

Dollar Lake

(SBCo.)Soledad Pd (SRI)

Abalone Rx (SRI)

Not Analyzed

Yet

Closed Coastal Conifer Forest

Inland Scrub (Coyote Brush) &

Grassland w/

halophytes

Closed Fir & Pine Forest

NO POLLEN PRESERVED

Coastal Sage

Scrub & Grassland

Coastal Sage Scrub

(More Coyote Brush, fewer Salt Marsh species)

0

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Cal Yr BP x 1000

0

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Cal Yr BP x 1000

Maritime Continental

Historic Period –

Introduced Herbs

(Rumex, Erodium, Plantago) and Trees

(Eucalyptus)

(33 m asl)

(275 m asl)

(0 m asl)

(35 m asl)

(2810 m asl)

Moist

Dry

Coastal Sage Scrub(More Salt

Marsh species,

Less Coyote Brush)

Sparse Coastal Sage Scrub

Coastal Sage

Scrub & Grassland

No Permanent

Water; Open

LodgepolePine Forest

Permanent Water

NO POLLEN PRESERVED

Southern California

Inland Scrub (Coyote Brush) & Grassland w/

Woodland Species; Riparian Species

Fire History Studies• Critical to our understanding of the

centennial and millennial-scale fire history is the history of fire over the last two centuries

• Little was known about the pre-Historic fire regimes on the Point Reyes Peninsula until the work of Finney (1990) and Brown et al. (1999)

Fire History Studies

• Brown et al. (1999)– Limatour Road and Five Brooks sites

– periodic fire from the 18th century until ca. 1905 (Five Brooks) or 1918 AD (LimatourRoad)

– Pre-settlement Mean Fire Intervals (MFI) [early 1800’s to ca. 1900 AD ] 7.7 to 8.5 years – characteristic of a surface fire regime


• Finney (1990)– Bolinas Ridge and the Kent Lake region

– Pre-settlement MFI 7.5 years for small fires, and < 2 years for larger fires

– Settlement MFI [last half of the 20th century] was an order of magnitude longer


• Change in fire regime in 20th century due to cessation of surface fire regime (Finney 1990; Brown et al. 1999) that probably existed during the pre-Historic period.

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ge (c

alen

dar y

ears

BP

)

Creamery Bay Bog(6 m asl)

particles/cm2/year

Glenmire(167 m asl)

Wildcat Lake(62 m asl)

Coast Trail Pond(230 m asl)

Shutter Ridge Pond(35 m asl)

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General Low Fire during Period of Coastal

Forest – Wet?

Grassland

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Douglas-fir

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Transition Period

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Consistently Higher Fire Occurrence – Humans ?

Why Synchronous Increase ?• Climate changes → wetter conditions, more biomass

• Human activities– Native American burning ethnographies

– Human habitation of Peninsula by coastal Miwok by 5000 years ago

– 14C dates on archaeological sites on and near Point Reyes increases after ca. 3500 years ago suggesting expanding human population

– These data are not conclusive of Human Burning, but are at least suggestive

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Historic Period –General

Decline in Fire

Occurrence (especially at Coast Trail

Pond, Wildcat Lake

& Shutter Ridge Pond)

Summary – General Considerations

• A complex relationship between vegetation, climate, human settlement & fire occurrence– Abundant charcoal produced, but conifer forest and

sage scrub produced more charcoal than did grassland during the Holocene.

– Climate affects the characteristics of each sedimentary basin – determining whether that basin will be perennially wet or periodically dry.

– Local conditions, in turn, affect the local vegetation at each site.

– Human activities can have a potentially large effect on both vegetation and fire history.

Summary – Vegetation Changes• Closed coastal conifer forest until ca. 10,200 yr

ago• Driest Period commenced ca. 10,000 yr ago• Early Holocene established Mixed forest &/or

coastal sage scrub (most locales) and grassland (CBB)

• Still reasonably dry until ca. 6500 yr ago• Modern vegetation established during late

Holocene• Greatest vegetation change is in Historic Period

Summary – Fire Histories• 15k to 10 k – Generally low fire occurrence during period

of coastal forest – Wet?• 10k to 5.5 k - Early Holocene peak in fire activity – dry

climate?• 5.5 to 3.5 k – vegetation change and corresponding fire

history adjustments• 3.5 k to Historic times – general increase in fire, climate

or humans?• Human activities may have had entirely different effects

on the fire regime at different times in the past– Native American populations potentially contributing to high fire

frequencies– Euro-Americans causing fire to become more rare, but perhaps

more destructive

Summary – General Considerations

• Many factors have been important in determining characteristics of vegetation and fire disturbance histories at Point Reyes.

• With increasing human impact on the landscape and our climate, retrospective studies are important

– in understanding how modern vegetation communities came to be as they are today

– as a reference for restoration of former habitats– as a baseline to determine the magnitude of future

impact of humans.

Heartfelt Thanks to: Douglas Hallett (NAU), Mitch Power (Univ Oregon), Dan Buckley (NPS),

Barbara Moritsch (NPS), Jane Rodgers (NPS), Wende Rehlaender (NPS),

Heather Adkins, (NAU), Allison Bair (NAU), Mark Daniels (ERI-NAU),

Kirsten Ironside (NAU), Renata Jass (NAU), Taylor Joyal (NAU), Caitilin

McCracken (NAU), Rob Richardson (NAU), Jaime Toney (NAU), Alison Forrestel

(NPS), Point Reyes GIS Staff

Documents

Scott Anderson 2-2-06 - NPS