fire ecology of juniper and pinyon-juniper woodlands fire ecology of juniper...western juniper...

70
Western juniper woodland Owyhee Mountains, Idaho Fire ecology of juniper and pinyon-juniper woodlands Ecology of Arid and Semi-arid lands

Upload: others

Post on 10-Mar-2020

51 views

Category:

Documents


0 download

TRANSCRIPT

Western juniper woodland

Owyhee Mountains, Idaho

Fire ecology of juniper and pinyon-juniper woodlands

Ecology of Arid and

Semi-arid lands

Common juniper and pinyon/juniper woodlands:

Western juniper (Juniperus occidentalis)

Utah juniper-singleleaf pinyon (J. osteosperma, P. monophylla)

Utah juniper-pinyon (J. osteosperma, P. edulis)

Oneseed juniper-pinyon (J. monosperma, P. edulis)

Redberry juniper (J. pinchotii)

Ashe juniper (J. ashei)

Eastern red “cedar” (J. virginiana)

Source: USGS, http://pubs.usgs.gov/pp/p1650-a/pages/conifers.html

Source: USGS, http://pubs.usgs.gov/pp/p1650-a/pages/conifers.html

Source: USGS, http://pubs.usgs.gov/pp/p1650-a/pages/conifers.html

Source: USGS, http://pubs.usgs.gov/pp/p1650-a/pages/conifers.html

Juoc

Juos

Jumo

Jupi

Juas

What climatic changes are occurring along this gradient?

Source: USGS, http://pubs.usgs.gov/pp/p1650-a/pages/conifers.html

Source: USGS, http://pubs.usgs.gov/pp/p1650-a/pages/conifers.html

Source: USGS, http://pubs.usgs.gov/pp/p1650-a/pages/conifers.html

Pinyon pine (Pinus edulis)

Owl Canyon, Larimer County,

Colorado

Source: USGS, http://biology.usgs.gov/luhna/chap9.html

Photos: 1950, J.D. Wright (above);

1989, R.M. Turner (right)

Oneseed juniper (Juniperus

monosperma),

Enchanted Mesa, Cibola

County, New Mexico

Photos: 1899, W.H. Jackson (above);

1977, H.E. Malde (right)

Source: USGS, http://biology.usgs.gov/luhna/chap9.html

Fire SuppressionIntroduction

Livestock

Es

tab

lish

men

t (%

)Woodland Age Structure

1650 1700 1750 1800 1850 1900 1950 2000

Fire event

Miller et al. 2005

Succession in a Western Juniper Community

Grassland after fire Mountain big

sagebrush steppeStand initiation juniper

(Phase 1)

Open young juniper

(Phase 2)

Young multistory juniper

(Phase 3)

Old multi-story juniper

Early western juniper encroachment

Miller et al. 2005

A conceptual model illustrating the relationship between shrub

cover, tree canopy cover, relative growth rates and management

strategies during the three phases of woodland development

Phase 3 woodland: low fine fuel loading

Mt Bluebirds

Mt Chickadees

Chipping sparrows

Flycatchers

Juncos

Sage thrasher

Sage sparrow

Brewers sparrow

Green tailed towhee

Vesper sparrow

Horned lark

Western Meadowlarks

Finches

10 25 50 100

Years

Photo: P. LaTourrette

Miller et al. 2005

Miller et al. 2005

Woodland ExpansionP

erc

en

t

0

2

4

6

8

10

12

14

1600 1650 1700 1750 1800 1850 1900 1950 2000

Decade

Perc

en

t

0

2

4

6

8

10

12

1600 1650 1700 1750 1800 1850 1900 1950 20001600 1650 1700 1750 1800 1850 1900 1950 2000

Miller and Tausch 2001, Miller et al. 2005

Factors influencing expansion of western juniper

since the late 1880’s and throughout the 1900’s.

Phase 3 woodland: pre-fire

Phase 3 woodland: 1st year post-burn

Phase 3 woodland: 1st year post-burn

Phase 3 woodland: 2nd year post-burn

Phase 3 woodland: 5th year post-burn

Phase 3 woodland: 7th year post-burn

Phase 3 woodland: 12th year post-burn

Phase 1 woodland: Pre-burn

Phase 1 woodland: 3rd year post-burn

Phase 1 woodland: 7th year post-burn

Current Creek

Smith Creek

Red Canyon Creek

Hurry Back Creek

Juniper Mountain, Owyhee Uplands, Idaho

Landsat 5 imagery, July 1992

Current vegetation within the Smith Creek

Watershed, Owyhee Plateau, Idaho

Low sagebrush steppe

Mountain big sagebrush steppe

Sagebrush steppe or young juniper

Juniper initiation woodland

Western juniper woodland

Mountain-mahogany woodland

Other

Smith Creek Watershed

1800

1900

1989

Species richness of vascular plants in various

stages of western juniper succession

Successional stage Number of species

Herbaceous 65

Sagebrush steppe 65

Young juniper woodland 60

Mature juniper woodland 70

Total number of species 133

Note: The number of species found at any sample location averaged

about 32 (Range = 28-37), regardless of the successional stage.

Common vascular plants of

the juniper woodland

Arrowleaf balsamroot

Wild onion

False dandelion

Mat wild-buckwheat

Skullcap

Silky lupine

Red Canyon Creek Smith Creek

1800 1900 1986 1800 1900 1986

280 210 132 410 363 163

23 31 49 17 19 42

0.014 0.013 0.010 0.016 0.015 0.009

Patch number

Mean patch

size (ha)

Edge density

(m/ha)

Changes in patch size and edge: 1800-1986

Patch size has increased and this has resulted in

the simplification of the landscape.

Red Canyon Creek Smith Creek

1800 1900 1986 1800 1900 1986

1.96 2.09 2.22 1.94 1.99 2.23

0.083 0.084 0.094 0.156 0.174 0.326

Mean patch

shape index

Mean patch

perimeter/area

ratio

Changes in patch shape: 1800-1986

Patch size have become more irregular in shape

as patch have coalesced into larger patches of

the same type.

Red Canyon Creek Smith Creek

1800 1900 1986 1800 1900 1986

77.4 68.2 60.7 72.4 65.6 58.8

1.69 1.47 1.39 1.80 1.62 1.54

0.87 0.82 0.78 0.82 0.78 0.74

Interspersion

Juxtaposition

Index

Shannon’s

diversity index

Shannon’s

evenness index

Changes in landscape diversity: 1800-1986

The landscape has become less diverse and

more dominated by a few patch types- those with

middle aged and mature juniper.

Why does the change to a landscape that is more

dominated by juniper matter?

- Species conservation

(Photo by M. Salvo USFWS)

Sage thrasher

Sage grouse

Applegate’s paintbrush

Why does the change to a landscape that is more

dominated by juniper matter?

- Species conservation

- Water conservation

Why does the change to a landscape that is more

dominated by juniper matter?

- Species conservation

- Soil and water conservation

- Forage

Why does the change to a landscape that is more

dominated by juniper matter?

- Species conservation

- Soil and water conservation

- Forage

- Fire behavior

Photo by Rick Miller

Mountain big sagebrush fuel loading by cover type

0.0

0.5

1.0

1.5

2.0

2.5

Artr Steppe Phase 1 Phase 2 Phase 3 Mature

Woodland

Fu

el lo

ad

ing

(M

ton

s / h

a)

1 Hour 10 Hour 100 Hour Live

GrassJuniper litter

Sagebrush stems

Mountain big sagebrush fuel bed depth by cover type

0

10

20

30

40

50

Artr Steppe Phase 1 Phase 2 Phase 3 Mature

woodland

Fu

el b

ed

de

pth

(c

m)

Fuel bed depth

Mountain big sagebrush flame length

and fuel bed depth by cover type

0

1

2

3

4

5

6

Artr Steppe Phase 1 Phase 2 Phase 3 Mature

woodland

Fla

me len

gth

(m

)

0

10

20

30

40

50

Fu

el b

ed

de

pth

(c

m)

Flame length

Fuel bed depth

Mountain big sagebrush fire behavior

0 50 100 150 200 250 300

Mature

woodland

Phase 3

Phase 2

Phase 1

Artr SteppeC

ov

er

typ

e

Rate of spread (m/min)

Western juniper/low sagebrush

woodlandTerry Spivey, USDA Forest Service, www.forestryimages.org

Low sagebrush fuel loading by cover type

0.0

0.5

1.0

1.5

2.0

2.5

Arar Steppe Phase 1 Phase 2 Mature

woodland

Fu

el lo

ad

ing

(M

ton

s / h

a)

1 Hour 10 Hour 100 Hour Live

Low sagebrush flame length by cover type

0

1.5

3

4.5

Arar Steppe W1 Arar W2 Arar W5 Arar

Fla

me

le

ng

th (

m)

Flame length

Arar steppe Phase 1 Phase 2 Mature

woodland

Low sagebrush flame length

and fuel bed depth by cover type

0

1.5

3

4.5

Arar Steppe Phase 1 Phase 2 Mature

woodland

Fla

me

le

ng

th (

m)

0

5

10

15

20

25

Fu

el b

ed

de

pth

(c

m)

Flame length

Fuel bed depth

Low sagebrush fire behavior

0 50 100 150 200

Mature

woodland

Phase 2

Phase 1

Arar Steppe

Co

ve

r ty

pe

Rate of Spread (m/min)

How do the changes in fire behavior

affect the watershed composition

Modeling Landscape

ChangeLooking into the future -

Ecological Modeling

Red Canyon Creek

Watershed

?

2025

Input data layers

created using GIS

Modeling in external

computer programs

VDDT and TELSA or

LANDSUM

Output linked to GIS

layer for final display

Landscape

analysis through

FRAGSTATS or

other stat package

Current vegetation cover type map

Management scenarios modeled

• Current wildfire management

• Prescribed fire- 2%/decade

• Prescribed fire- 5%/decade

• Prescribed fire- 7%/decade

• Prescribed fire- 5%/decade, including

young multistory woodlands

Photo by Rick Miller

How much fire is necessary to

maintain landscape diversity?

Watershed area (%) Present 50 yr 100 yr 200 yr

Present 50 years 100 years

200 years

Grassland 0.7 0.9 1.3 1.5

Low sagebrush 4.4 3.9 4.0 3.9

Mtn big sagebrush 1.4 3.2 2.2 2.3

Phase 1 juniper 0.3 4.3 2.1 1.1

Phase 2 juniper 19.9 11.6 3.3 0.7

Phase 3 juniper 34.4 53.4 58.0 47.2

Old multi-story jun.11.2 16.2 23.4 38.3

Mtn-mahogany 2.6 2.6 1.5 1.4

Smith Creek Watershed- Wildfire only

Smith Creek - after 100 years under current fire

occurrence

Other landscape metrics:

Simpson’s evenness index declines.

Landscape diversity deceases.

Contagion index increases.

Interspersion-Juxtaposition index decreases.

Total edge decreases.

Smith Creek Watershed Composition after 100 years

Present Wildfire 2% Rx

5% Rx 7% Rx5% Rx including

Phase 2 woodlands

Area of mountain big sagebrush steppe in

Red Canyon Creek under varying prescribed

fire regimes (Steppe and Phase I).

0

400

800

1200

1600

2000

present 50 100 200

Current mgt

2%/decade

5%/decade

7%/decade

Time period (yrs in future)

Are

a (

ha)

Fire management

regime

Note: Values are

an average of 10

model runs.

Area of mountain big sagebrush steppe in

Smith Creek under varying prescribed fire

regimes (Steppe and Phase I).

Time period (yrs in future)

Are

a (

ha

)

Fire management

regime

Note: Values are

an average of 10

model runs.

0

200

400

600

800

1000

present 50 100 200

Current

Rx fire 2%

Rx fire 5%

Rx fire 7%

Grass/Forb herbland 0.7 1.3 2.6 4.9 6.9 4.9

Low sage steppe 4.4 4.0 4.8 8.2 9.6 7.0

Mountain sage steppe 1.4 2.2 4.2 10.8 13.8 10.7

Phase 1 juniper woodland 20.3 2.1 6.4 8.4 7.8 11.5

Phase 2 juniper woodland 19.9 3.3 2.9 2.0 1.0 3.5

Phase 3 juniper woodland 34.4 58.0 50.1 36.7 32.2 37.4

Mature juniper woodland 11.2 23.4 23.6 23.5 23.3 19.9

Mountain-mahogany 2.6 1.5 0.5 0.1 0.0 0.5

Present Wildfire 2% Rx 5% Rx 7% Rx 5%+

Phase2

Smith Creek - cover after 100 years under

different fire scenarios

Watershed area (%)

Amount per decade

Tongue Complex Fire

July 6-29, 2007

Total area: 46,680 acres

Ignition source: Lightning

*

*

USDI BLM map and photo

Tongue Complex Fire 7-15-07

Red Canyon Creek

Tongue Complex Fire, July 2008: 1st growing season postburn

Tongue Complex Fire, July 2008: 1st growing season postburn

Tongue Complex Fire, July 2008: 1st growing season postburn

Sagebrush steppe

Phase I

Tongue Complex Fire, July 2009: 2nd growing season postburn

Phase II

Tongue Complex Fire, July 2009: 2nd growing season postburn

Phase III

Tongue Complex Fire, July 2009: 2nd growing season postburn