THE ROLE OF BIOTIC AND ABIOTIC STRESSORS IN - PDF document

1 THE ROLE OF BIOTIC AND ABIOTIC STRESSORS
THE ROLE OF BIOTIC AND ABIOTIC STRESSORS IN JEFFREY PINE SUSCEPTIBILITY TO JEFFREY PINE BEETLE Nancy Grulke USDA Forest Service ngrulke@fs.fed.us Assumptions  Bark beetle attacks are more common in dense stands or in marginal populations  Drought increases pine susceptibility to bark beetle Approach  Quantify level of tree - tree competition  T

2 est for differences in physiological dro
est for differences in physiological drought stress in:  different stand densities and  between attacked and unattacked trees  Relate physiological drought stress to resin exudation rate  Test for definitive spectral signature using high resolution remote sensing to assist management of east - side dry pine forests Right:

3 Pinus Jeffreyi ( Grev . & Balf .)
Pinus Jeffreyi ( Grev . & Balf .) (right), attacked by Dendroctonus jeffreyi (Hopkins); Site selection: core sites (east side)  Lassen NF  Tahoe NF  Inyo NF  Sequoia NF  San Bernardino NF SOUTHERN CASCADES SIERRA NEVADA TRANSVERSE RANGE Crater Lake NP Lassen Volcanic NP, Lassen NF Tahoe NF Sequoia NP, Sequoia NF San Ber

4 nardino NF San Pedro Martir NP Inyo
nardino NF San Pedro Martir NP Inyo NF Also draw upon other studies of Pinus ponderosa (var. pacifica and scopulorum ) to answer questions (all in ResearchGate /Grulke) Fremont NF Tree selection (core work)  Chose 6 - 7 stands:  3 thinned (10 - 30 yrs ago)  3 dense  p rescribed or wildfire burns (not presented here)  In eac

5 h stand, the first 8 mature trees (90 to
h stand, the first 8 mature trees (90 to 120 yr old) were chosen within a belt transect  ~280 trees in the study Competition: stand density vs. nearest neighbors  We use stand density, but it only takes one stressed tree to initiate a bark beetle outbreak  The neighboring trees drive biotic pressure, not stand density per se Stand basal area vs. tree

6 - tree competition BASAL AREA: 30 m D
- tree competition BASAL AREA: 30 m DIAMETER PLOT TOTAL AREA, ALL TREES BY SPECIES NEAREST NEIGHBOR: 25 m RADIUS OUT FROM TARGET (CENTER) TREE, LIST BA AND SPECIES OF NEAREST TREE IN EACH QUADRAT, EXCLUDING TREES cm DBH Latitudinal gradient of stand basal area (BA): DENSE AND THIN STAND BA DIFFERED BY 2 FOLD 0 10 20 30 40 50 60 70 BASAL AREA, m 2 HA - 1 B

7 A/ha PIJE SOUTH TO NORTH NEARLY PURE
A/ha PIJE SOUTH TO NORTH NEARLY PURE STANDS OF PIJE PIJE, PIPO, ABCO, LIDE ALL TREES PIJE NO RELATIONSHIP between stand density (x) and distance to nearest neighbor (y) 0 5 10 15 20 25 30 0 20 40 60 80 Distance to Nearest Tree, m Total Basal Area/HA, all species ANY SPECIES, SINGLE NN NO RELATIONSHIP between stand density (x) and distance to nearest

8 neighbor (y) 0 5 10 15 20 25 30 0 20
neighbor (y) 0 5 10 15 20 25 30 0 20 40 60 80 Distance to Nearest Tree, m Total Basal Area/HA, all species 0 5 10 15 20 25 30 0 20 40 60 80 Distance to Nearest PIJE, m Total Basal Area/HA, PIJE 0 5 10 15 20 25 30 0 20 40 60 80 Ave Distance to Surrounding PIJE, m Total Basal Area/HA, PIJE ANY SPECIES, SINGLE NN PIJE, SINGLE NN PIJE, AVERAGE of 4 QUADRAT

9 S Competition, summary • Across 5
S Competition, summary • Across 5 Forests, most PIJE is within 6 m of another PIJE, and averaged 4 m (bole center to bole center) • Many trees have canopy to canopy contact • Distribution the result of ‘clumpy/ gappy ’ management • BB attacked trees were more often in thinned stands, but occurred in denser clumps with - in those stands

10 0 5 10 15 20 25 30 35 40 45 Total BA/
0 5 10 15 20 25 30 35 40 45 Total BA/ha Total BA/ha, PIJE Basal Area (m2)/ ha unattacked attacked Competition, summary • Across 5 Forests, most PIJE is within 6 m of another PIJE, and averaged 4 m (bole center to bole center) • Many trees have canopy to canopy contact • Distribution the result of ‘clumpy/ gappy ’ management • BB attacked trees were mor

11 e often in thinned stands, but
e often in thinned stands, but occurred in denser clumps with - in those stands • We may be thinning stands, but we are not reducing within - species competition… 0 5 10 15 20 25 30 35 40 45 Total BA/ha Total BA/ha, PIJE Basal Area (m2)/ ha unattacked attacked  WHAT DO WE KNOW ABOUT PHOTOSYNTHETIC CAPACITY AND WATER USE EFFICIENC

12 Y OF JEFFREY PINE IN MARGINAL POPULATIO
Y OF JEFFREY PINE IN MARGINAL POPULATIONS? MARGINAL POPULATIONS? ELEVATIONAL AND LATITUDINAL VARIATION IN GROSS PHOTOSYNTHESIS OF JEFFREY PINE Low - elevation populations had lower Pg than at mid or higher elevations. Northern - most, highest elevation population had the highest Pg , and most ‘flexibility͘’ Grulke (2007) MARGINAL POPULATIO

13 NS? ELEVATIONAL AND LATITUDINAL VARIAT
NS? ELEVATIONAL AND LATITUDINAL VARIATION IN WATER USE EFFICIENCY OF JEFFREY PINE LITTLE DIFFERENCE IN WATER USE EFFICIENCY (WUE) ACROSS A LARGE LATITUDINAL GRADIENT; LESS WUE AT LOWEST ELEVATION AND LATITUDE SITE Grulke (2007) Attack and mortality observations over 3 years  9% of Jeffrey pine trees were attacked by Jeffrey pine beetle  7%

14 attacks in thinned stands; 2% in dense s
attacks in thinned stands; 2% in dense stands  4% attacks in northern stands, 3% in southern stands  1% died of flat headed wood borer (Lassen NF)  Mantgem & Stephenson (2007) report 3% mortality for west slope mixed conifer Sierran stands; In this study, mortality averaged 1.6% in dense stands and 16.6% in thin stands Most mortalit

15 y occurred 1 yr after attack 0 5
y occurred 1 yr after attack 0 5 10 15 20 25 30 LNF TNF INF SNF SBNF % PIJE ATTACKED BY JPB DENSE THIN summed over 3 years Primary abiotic stressor: DROUGHT! Primary abiotic stressor: DROUGHT!  Total annual precipitation ( ppt )  S oil water availability  Evapotranspiration  D rought index  Annual % average precipitation …but how i

16 s ‘drought’ related or correlated t
s ‘drought’ related or correlated to physiological tree drought stress? Attributes that DON’T define physiological drought stress 6 am 12 pm 6 pm Ψ total Ψ P (turgor) Ψ PD total (PREDAWN) Ψ SN total (SOLAR NOON) Ψ S+M TISSUE WATER POTENTIAL NEGATIVE POSITIVE } = Δ Ï

17 ˆ total 6 am
ˆ total 6 am 12 pm 6 pm Ψ total Ψ P Ψ PD total Ψ SN total Ψ S+M TISSUE WATER POTENTIAL NEGATIVE POSITIVE CELL TURGOR MAINTAINED OSMOREGULATION NOT PHYSIOLOIGCALLY DROUGHT STRESSED 6 am 12 pm 6 pm Ψ P (turgor) TISSUE WATER POT

18 ENTIAL NEGATIVE POSITIVE
ENTIAL NEGATIVE POSITIVE CELL TURGOR LOST INSUFFICIENT CELL OSMOREGULATION PHYSIOLOGICALLY DROUGHT - STRESSED Ψ total Ψ S+M SAME NOON FOLIAR WATER POTENTIAL, ONE STRESSED, ONE NOT Definition Of Drought Stress Moderate drought stress • reduction in cell turgor (e.g., elongation growth) • reduction in stomatal conductance Severe dr

19 ought stress • reduction or loss of
ought stress • reduction or loss of cell turgor, • reduction in stomatal conductance or stomatal closure • concentration of cell osmoticum (changes enzymatic function) • cell death Levitt, 1980 Total annual ppt, cm Physiological drought stress of ponderosa pine is related to the % of average precipitation within the same year. D

20 rought, and physiological drought stress
rought, and physiological drought stress, is common (Grulke et al. 2010). 120 yr regional precipitation record from Big Bear Dam 120 year average precipitation (ave ppt) 80% of ave ppt induces moderate drought stress ( 16% of time ) 60% of ave ppt induces extreme drought stress ( 30% of time ) SBNF SNF INF TNF LNF LONG TERM PRECIPITATION RECORDS FOR

21 EACH SITE: EXPRESSED CURRENT YEAR PPT
EACH SITE: EXPRESSED CURRENT YEAR PPT AS % OF AVERAGE SNF S BERDO SEQUOIA INYO TAHOE LASSEN 1990 77 52 83 84 59 1991 106 90 88 82 65 1992 118 119 93 65 52 1993 236 151 122 134 141 1994 101 75 82 61 69 1995 182 197 149 183 188 1996 83 115 109 152 131 1997 110 132 120

22 159 151 1998 173 158 141 146
159 151 1998 173 158 141 146 165 1999 53 75 80 133 106 2000 73 80 76 99 116 2001 63 60 104 60 61 2002 30 69 87 92 89 2003 94 92 122 102 117 2004 58 73 89 82 103 2005 181 148 165 99 107 2006 86 131 135 128 156 2007 31 58 45 51 47 2008 104 96 68 63

23 56 2009 41 29 44 24 23 MU
56 2009 41 29 44 24 23 MUSTARD: 60%; GRAY GREEN: 61 - 80%; AQU�A: 95% WIDE RANGE OF PRECIPITATION OVER THE FIRST 3 YRS OF INTENSIVE STUDY Needle and lateral branchlet elongation growth is a simple, integrated measure of the level of drought stress experi - enced by an individual tree within a stand. Needle elongation growth was expre

24 ssed as % of maximum growth observed fo
ssed as % of maximum growth observed for all retained needle age classes. This relative measure corrects for canopy position and nearest neighbor effects. 2002 2003 2000 NEEDLE AND BRANCH ELONGATION GROWTH: simple proxy for physiological drought stress 2001 NORTHERN SITE: TREES IN DENSE STANDS WERE MORE DROUGHT - STRESSED THAN IN THINNED STANDS.

25 RESPONSE WAS SUBTLE BUT PREDICTABLE R
RESPONSE WAS SUBTLE BUT PREDICTABLE R² = 0.6628 R² = 0.7134 0 10 20 30 40 50 60 70 80 90 100 0 50 100 150 200 % of Maximum Needle Length % Average Precipitation NL, dense NL, thin Linear (NL, dense) Linear (NL, thin) SOUTHERN 4 SITES: LOWER PPT SIGNIFICANTLY INCREASED PHYSIOLOGICAL DROUGHT STRESS. DROUGHT STRESS DID NOT DIFFER BETWEEN DENSE AND THINNED STAN

26 DS NORTHERN SITE: TREES IN DENSE S
DS NORTHERN SITE: TREES IN DENSE STANDS WERE MORE DROUGHT - STRESSED THAN IN THINNED STANDS. RESPONSE WAS SUBTLE BUT PREDICTABLE R² = 0.6628 R² = 0.7134 0 10 20 30 40 50 60 70 80 90 100 0 50 100 150 200 % of Maximum Needle Length % Average Precipitation NL, dense NL, thin Linear (NL, dense) Linear (NL, thin) R² = 0.6203 R² = 0.4117 0 10 20 30 40 50 6

27 0 70 80 90 100 0 50 100 150 200 % of Max
0 70 80 90 100 0 50 100 150 200 % of Maximum Needle Length % Average Precipitation NL, dense NL, thin Log. (NL, dense) Log. (NL, thin) Physiological response attribute: % needle length T his physiological attribute wasn’t refined enough to test for the difference between attacked and unattacked trees 0 10 20 30 40 50 60 70 80 90 100 % NL 06 % NL 07 % NL 08

28 % NL 09 % of Maximum Needle Length una
% NL 09 % of Maximum Needle Length unattacked attacked Definition Of Drought Stress Moderate drought stress • reduction in cell turgor • reduction in stomatal conductance Severe drought stress • reduction or loss of cell turgor, • reduction in stomatal conductance or stomatal closure • concentration of cell osmoticum (changes enzymatic fu

29 nction) • cell death PHYSIOLOGICAL
nction) • cell death PHYSIOLOGICAL DROUGHT STRESS Attacked Unattacked Delta, Mpa : Significant? Needle Ψ total PD Low Higher 0.10 NS Needle Ψ total SN Low Higher .05 NS Needle Ψ total Δ (SN – PD) Low Higher 0.16 NS Needle Ψ turgor SN Low Higher 0.13 NS Bole Cambium Ψ total Low Higher 0.10

30 NS Bole Cambium Ψ turgor Low
NS Bole Cambium Ψ turgor Low Higher 0.87 *** Key Results – RESIN EXUDATION IS BEST CORRELATED TO BOLE WATER POTENTIAL -2 0 2 4 6 8 10 12 ATTACKED CLEAN 1.2 1.0 .8 .6 .4 .2 0 - .2 Ψ turgor Cambium ( MPa ) Cambial turgor potential is lower in attacked trees Attacked Unattacked Delta, Mpa : Significant? Bol

31 e Cambium Ψ total Low Higher 0
e Cambium Ψ total Low Higher 0.10 NS Bole Cambium Ψ turgor Low Higher 0.87 *** Key Results – RESIN EXUDATION IS BEST CORRELATED TO BOLE WATER POTENTIAL -2 0 2 4 6 8 10 12 ATTACKED CLEAN 0.0 0.2 0.4 0.6 0.8 1.0 1.2 0 10 20 30 40 50 RESIN EXUDATION, g/h Bole Cambium Ψ total ( MPa ) Less Resin 0 - 1 - 2

32 - 3 - 4
- 3 - 4 - 5 Lower total water potential Threshold? 1.2 1.0 .8 .6 .4 .2 0 - .2 Ψ turgor Cambium ( MPa ) Cambial turgor potential is lower in attacked trees Trees with lower Ψ total express less resin Attacked Unattacked Delta, Mpa : Significant? Bole Cambium Ψ total Low H

33 igher 0.10 NS Bole Cambium Ψ tur
igher 0.10 NS Bole Cambium Ψ turgor Low Higher 0.87 ***  CAN TREE DROUGHT STRESS BE IDENTIFIED USING REMOTE SENSING? TEST TO REMOTELY DISTINGUISH TREE DROUGHT STRESS: APPROACH Image credit͗ Saint Mary’s College, CA WEST - SIDE SIERRA NEVADA SITE, SEQUOIA NATIONAL PARK 132 JEFFREY PINE IN MESIC AND XERIC MICROSITES PHYSIOLOGICAL DROU

34 GHT STRESS OF EACH TREE DOCUMENTED (Gru
GHT STRESS OF EACH TREE DOCUMENTED (Grulke et al., 2002a; b) MEASURED AND TESTED ADEQUACY OF 14 ATTRIBUTES OF CANOPY HEALTH AND 3 BANDS OF SPECTRAL DATA (+ ASSOC INDICES) PARTIALLY VALIDATED PREDICTIVE CAPABILITY ON A SITE 30 km N Thermal Images PATTERNS OF WITHIN - CANOPY MORTALITY TOP - DOWN BRANCH DRYING/ MORTALITY: PE

35 STS & PATHS BOTTOM - UP BRANCH DRYIN
STS & PATHS BOTTOM - UP BRANCH DRYING/ MORTALITY: DROUGHT TEST FOR ABILITY TO DISTINGUISH TREE DROUGHT STRESS AND HEALTH Image credit͗ Saint Mary’s College, CA SEPARATED SPECTRAL DATA INTO TOP AND UPPER MID - CANOPY SECTIONS OF THE TREE MASKED SHADED PORTION OF THE CANOPY RANDOMLY SAMPLED SPECTRAL SIGNATURE OF 30 POINTS IN EACH SHAPE FILE ‘UNSE

36 EN’ Correlation of remotely s ensed
EN’ Correlation of remotely s ensed and canopy health attributes Spectral Canopy Health Top Canopy R ed Whorl # NIR Chlorotic mottle 1 R:NIR Chlorotic mottle 2 NIR Scalar Chlorotic mottle 4 NDVI Chlorotic mottle 6 Thermal % Needle length Upper M id Canopy Red % branchlet foliation NIR Branchle

37 t Diameter 2 R:NIR C one frequency
t Diameter 2 R:NIR C one frequency NIR Scalar Leaf s cale NDVI Leaf cutter Thermal Mistletoe Δ’s (top - mid) R ed ∆ Elytroderma NIR ∆ Early senescence R͗NIR ∆ NIR scl ͘ ∆ NDVI ∆ Therm͘ ∆ Red (650 nm), NIR (860 nm), thermal (8.1 - 12.4 nm) bands Canonical Correlation Analysis: Significance of squares

38 Adj. R: Pillai’s trace
Adj. R: Pillai’s trace = ͘023 X | Y = ͘07 Y | X = .04 Classification tree model Grulke, et al. Remote detection and attribution of Jeffrey pine canopy health and drought stress in the south central Sierra Nev ada. (in prep) Initial classification tree model:

39
• THE Δ THERMAL WAVELENGTH BETWEEN UPPER AND MID CANOPY ALONE COULD DEFINITIVELY DISTINGUISH TREES WITH DIFFERING LEVELS OF PHYSIOLOGICAL DROUGHT STRESS • ADDING Δ NDVI IMPROVED PREDICTIVE CAPACITY Classification tree model Grulke, et al. Remote detection and attribution of Jeffrey pine canopy health and drought stre

40 ss in the south central Sierra Nev ada.
ss in the south central Sierra Nev ada. (in prep) Initial classification tree model: 2 nd site for partial validation: • THE Δ THERMAL WAVELENGTH BETWEEN UPPER AND MID CANOPY ALONE COULD DEFINITIVELY DISTINGUISH TREES WITH DIFFERING LEVELS OF PHYSIOLOGICAL DROUGHT STRESS • ADDING Δ NDVI IMPROVED PREDI

41 CTIVE CAPACITY Conclusions - I ST
CTIVE CAPACITY Conclusions - I STAND DENSITY EFFECTS ON DROUGHT STRESS, BARK BEETLE ATTACK AND TREE MORTALITY  At the northern - most site, trees in dense stands were more drought - stressed than in thinned stands, but south of Lassen NF, this didn’t hold true  No apparent difference in attack or mortality rates between northern and southern latitudes

42  Attacked Jeffrey pine was 8x more
 Attacked Jeffrey pine was 8x more frequent in thinned stands, but mortality occurred in dense clumps within those stands  implications for ICO, clumpy/ gappy management  Thinned stand mortality was 5x greater, and dense stand mortality was 2x greater In east - side PIJE - dominated stands than in mixed conifer stands in west - side Sierra Nevada stands (van

43 Mantgem & Stephens 2007) Conclusio
Mantgem & Stephens 2007) Conclusions - II PHYSIOLOGICAL DROUGHT STRESS EFFECTS ON TREE SUSCEPTIBLITY TO BARK BEETLE ATTACK AND ITS (REMOTE) DETECTION  Physiological drought stress decreased the tree’s capacity to physically repel beetles:  attacked trees were more drought - stressed than unattacked trees (lower cell turgor), and  lower cambia

44 l water potential was correlated with lo
l water potential was correlated with lower resin flow  Tree drought stress can be detected and attributed using high resolution remote sensing tools:  the Δ thermal wavelength alone can be used to identify trees in mesic vs. xeric microsites  Remotely detected tree drought stress could be used to:  identify stands at risk (bark beetle, wildfire

45 ) and  to select the most at - ris
) and  to select the most at - risk individual trees to be removed in thinning operations TOOLS FOR ID’ing DROUGHT STRESS  Significant signs of severe drought stress:  Lower canopy primary branch excision; growing point dieback  Whole tree desiccation  Within whorl needle excision Fremont N

46 ational Forest, south - central Oregon
ational Forest, south - central Oregon, 2014 - 2015 ~25% of ave ppt Interior ponderosa pine  Significant signs of severe drought stress:  Lower canopy primary branch excision; growing point dieback  Whole tree desiccation  Within whorl needle excision NEEDLE AGE CLASSES OLDER THAN CURRENT YEAR WE

47 RE AFFECTED Typically there is a stead
RE AFFECTED Typically there is a steady increase in needle chlorosis or chlorotic mottle as needles age (Sequoia National Park, P. Jeffreyi ; San Bernardino NF, P. ponderosa var. pacifica ) % chlorotic mottle Typically there is a steady increase in needle chlorosis or chlorotic mottle as needles age (Sequoia National Park, P. Jeffreyi ; San Bernardino NF, P.

48 ponderosa var. pacifica ) Extreme d
ponderosa var. pacifica ) Extreme drought stress in P. ponderosa var. scopulorum (Fremont NF) has significantly increased chlorosis in needles older than current year % chlorotic mottle Sequoia National Park, Jeffrey pine Jeffrey pine experienced 57% of average precipitation (based on 60 yr record) in 2007 • SIGNIFICANT WHORL LOSS FROM 2007 DROUGH

49 T, ~0.5 WHORLS LOST IN ONE YEAR IN XER
T, ~0.5 WHORLS LOST IN ONE YEAR IN XERIC SITES • NO SIGNIFICANT WHORL LOSS IN MESIC SITES • In interior ponderosa pine, we expect 2 to 4 needle age classes to be lost this year in south central OR In excising branches, there is a high incidence of: • scale • sap - sucking insects • leaf cutters (caterpillars) • needle tip dieback • whol

50 e needle dieback • loss of needle ag
e needle dieback • loss of needle age classes • loss of needles within a whorl 0.00 0.05 0.10 0.15 0.20 0.25 0.30 MC MF XC XF NEEDLE SCALE Sequoia National Park, Jeffrey pine mortality 1998 - 2008 CAUSE OF MORTALITY: BARK BEETLE 5 in the last 10 yrs was 60% of avg ppt The physiological drought stress was translated to morphological indicators in the

51 canopy: • whorl loss • within wh
canopy: • whorl loss • within whorl needle loss • reduced needle elongation • reduced branch and bole growth • high incidence of foliar insects • • • • And high mortality Since 2008, only a few more trees have died, all in the xeric (unfertilized) microsites Assessing tree drought stress without toys  Track site % of averag

52 e precipitation  Measure % of maxim
e precipitation  Measure % of maximum needle elongation  Look for LOTS of foliar insects and pathogens  Look at whole tree foliar discoloration and location in canopy  Use remote sensing tools to identify and eliminate drought stressed trees in thinning prescriptions Acknowledgments • Steve Seybold PSWRS USFS • Andy Graves UC Davis � R3 FHP

53 • Mary Kay Herzenach U Colorado
• Mary Kay Herzenach U Colorado • Jason Maxfield Portland State University • Miles Daly U of Colorado • Flavio Peggion U of Florence • Danielle Cibecchini U of Florence • Danielle Olivero U of Florence • Jessica Drodz U of Colorado • Lassen , Tahoe, Inyo, Sequoia, and San Bernardino National Forests • Sequoia National P