Forest Health and Mortality Trends Across Three Elevation Zones in - - PowerPoint PPT Presentation

Forest Health and Mortality Trends Across Three Elevation Zones in the Lake Tahoe Basin

Camille Jensen1, Patricia Maloney1 and Detlev Vogler2

1University of California, Davis, Tahoe Environmental Research Station 2USDA Forest

Service, PSW Research Station, Institute of Forest Genetics

• insect pests
• pathogens
• parasitic plants
• invasive plants
• fire
• tree density
• land-use (grazing, clearing)
• soil (compaction)
• climate (precipitation, temperature)

Factors Affecting Forest Health

lower montane upper montane subalpine

Study Sites

• 2008-2010 plots established
• data collected

Objectives

• Determine mortality levels

(associated variables)

• Assess damage

(caused by insects/diseases)

• Identify declining populations

Vvv Vvv

Vvv n

2000m (6560ft) 2450m (8040ft) 2800m (9190ft)

Summary of Stand and Environmental Data at Three Elevation Zones in the Lake Tahoe Basin

Elevation Zone Mean elev

m

Assoc. spp(%) Min- Max temp

• C

Ann ppt

mm

AWC 50 Density

st/ha

Basal Area

m2/ha

Mort- ality

%

Land- use (%) subalpine 2805 pial (89) tsme (4) pico (3) 7.5- 22.2 1209 2.8 607

(461-846)

26

(18-35)

2.6

(0.5-4)

REC(20) WF (10) upper montane 2450 pimo(46) abma(36) pico(10) 7.4- 22.7 1123 4.2 179

(98-269)

26

(11-47)

10.8

(0.7-21)

RT (20) WF (20) lower montane 2026 abco(52) pila(27) pije(14) 7- 23.7 802 5.2 235

(62-360)

20

(5-42)

9.4

(3-20)

HL (90) RT (20) PF (20)

Notes: Means displayed for each elevation zone (range); Soil data source: USDA NRCS (http://websoilsurvey.nrcs.usda.gov/app/HomePage.htm) Climate average for each region based on PRISM data for 30-year averages (Daly et al. 1994 and FHTET), AWC 50 = available water in top 0-50 in; Land-use: HL=historical logging, RT=recent thinning, WF=wild fire, PF=prescribed fire, REC=recreation.

10 20 30 40 50

• P. lambertiana
• A. concolor
• P. monticola
• A. magnifica
• P. albicaulis

lower montane upper montane subalpine 10 20 30 40

lower montane upper montane subalpine

% mortality

Tree Mortality by Elevation Tree Mortality by Species

Insect and Disease Incidence Across Elevation Zones White Pine Blister Rust (Cronartium ribicola)

0% 5% 10% 15% 20% 25% 30% 35% 40%

Pinus lambertiana Pinus jeffreyi Abies concolor Pinus monticola Abies magnifica Pinus contorta Pinus albicaulis lower montane upper montane subalpine

incidence C.ribicola H.annosum M.caryophyllacearum Arceuthobium spp. D.ponderosae S.ventralis

Subalpine - White Pine Blister Rust (C. ribicola)

10% 54% 10% 13% 35% 7% 0% 3% 0% 13% 1% 5% 8% 48% 18% 3% 6% 65% 36% 3% 15% 2% 10% 31% 23% 43% 15% 44%

Trap locations xxx

• Negative relationships between cone production and WPBR incidence and severity
• Percent of individuals infected (incidence),

avg number of infected branches per population, and severity of stem girdling - all negatively related with cone production

lower montane upper montane subalpine

1000 2000 3000 4000 5000 10 20 30 40 50 60 70 WPBR incidence (%) 1000 2000 3000 4000 5000 1 2 3 4 5 6 Average number of branch cankers per tree

1000 2000 3000 4000 5000 0.00 0.25 0.50 0.75 1.00 1.25 1.50 Average stem girdle category population-

R2 = 0.78, P = 0.003 R2 = 0.72, P = 0.008 R2 = 0.76, P = 0.005

0% 5% 10% 15% 20% 25% 30% 35% 40%

Pinus lambertiana Pinus jeffreyi Abies concolor Pinus monticola Abies magnifica Pinus contorta Pinus albicaulis lower montane upper montane subalpine

incidence C.ribicola H.annosum M.caryophyllacearum Arceuthobium spp. D.ponderosae S.ventralis

Insect and Disease Incidence Across Elevation Zones Mountain Pine Beetle (Dendroctonus ponderosae)

Upper Montane - Mountain Pine Beetle (D. ponderosae)

11% 3% 3% 8% 3% 9% 0% 0% 28% 4% 2% 7% 1% 0% 1% 3% 3% 1% 1% 3% 2% 5% 7% 0% 9% 7% 15% 0%

Trap locations

lower montane upper montane subalpine

• Positive relationship between

% mortality and mt pine beetle (incidence) in the upper montane zone

5 10 15 20 25 30 35

• 5

5 10 15 20 25 30 35 40

• mt. pine beetle (P<.0001)

Lower Montane - Heterobasidion occidentale

(aka H. annosum (S), annosus root rot)

0% 5% 10% 15% 20% 25% 30% 35% 40%

Pinus lambertiana Pinus jeffreyi Abies concolor Pinus monticola Abies magnifica Pinus contorta Pinus albicaulis lower montane upper montane subalpine incidence

C.ribicola H.annosum M.caryophyllacearum Arceuthobium spp. D.ponderosae S.ventralis

• Positive relationship between H. occidentale

(incidence) and tree mortality in the lower montane zone

QuickTime™ and a decompressor are needed to see this picture.

http://www.slu.se/en/department-of-forest-mycology-and-pathology

• 5

5 10 15 20 25

• 5

5 15 25 H.occidentale

1) Scolytis ventralis 2) Melampsorella caryophyllacearum 3) Arceuthobium spp.

• Additional insect, pathogen

and parasitic plant affecting forest health - no direct relationship to mortality

All Elevation Zones

0% 5% 10% 15% 20% 25% 30% 35% 40% Pinus lambertiana Pinus jeffreyi Abies concolor Pinus monticola Abies magnifica Pinus contorta Pinus albicaulis lower montane upper montane subalpine incidence C.ribicola H.annosum M.caryophyllacearum Arceuthobium spp. D.ponderosae S.ventralis

X

Acknowledgements: Input and suggestions provided by: Roland Shaw, Nevada State Parks, Rich Adams and Tamara Suzuki, California State Parks, Dave Fournier, USDA Forest Service. Field assistance provided by: Tom Burt Funding: Sierra Nevada Public Lands Management Act (SNPLMA-R7)