Trees in a Changing EnvironmentCan we/they adapt fast enough?

John MexalProfessor of Tree Necrology

Department of Plant & Environmental Sciences New Mexico State University

What would the Botanical Butchers of Broadway do? What would they do?

~Apr. 1997

Maybe something truly spectacular?

Botanical equivalent of “butt-crack” syndrome!

This is what I found!!

Jan. 2006~Apr. 1997

http://data.giss.nasa.gov/gistemp/2005/

Is it hot in here? Or what?

I’m baaack!!!

• What human nature would not or could not do…

• Mother Nature is doing it!

• Climate Change will claim more trees as it gets hotter and drier over the next several decades.

How to get there?

Human Nature

How to get there?

Human Nature

How to get there?

Mother Nature

How to get there?

Mother Nature

http://www.weatherstock.com/

How to get there?

T

Ppt

Mother Nature

ΔTCO2

How to get there?

↑T

↑EC

↑ET

↑Rs

↓netPs

↓Ts

↓Ppt

Mother Nature↑Ts

↑ΔT

↑Tinjury

↑Disease

↓Ψsoil

↑CO2

↓Ps

How to get there?

↑T

↑EC

↑ET

↑Rs

↓netPs

↓Ts

↓Ppt

Mother Nature↑Ts

↑ΔT

↑Tinjury

↑Disease

↓Ψsoil

↑CO2

↓Ps

One way or another!

Climate Change

• Is it getting hotter?

• Is it getting drier?

• What will happen to my trees.

Is it hot in here? Or what?

Climate Change: Forests vs Grasslands

Current 2050

Climate Change: Western Redcedar

Current 2050

http://data.giss.nasa.gov/gistemp/2005/

Is it hot in here? Or what?

http://data.giss.nasa.gov/gistemp/2005/

New Mexico

Is it hot in here? Or what?

Change in vegetation with climate change/ Aber et al. Biosci. 51(9):735:2001

Hadley Centre for Climate Prediction ΔT = 2.8C

Change in vegetation with climate change/ Aber et al. Biosci. 51(9):735:2001

Canadian Global Coupled Model ΔT = 5.2C

Climate Change in the SW US

11

12

13

14

15

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17

1930 1940 1950 1960 1970 1980 1990 2000 2010Year

Tem

per

atu

re (

C)

AZ - C

NM - C

AZ = 0.067x - 116.46R2 = 0.94

NM = 0.044x - 75.39R2 = 0.84

Global Temperature

Top 26 warmest years61% in last 30 yrs

Rank Year oF 1 2006

55.012 1998 54.94 3 1934

54.91 4 1999 54.53 5 1921 54.49 6 1931 54.34 7 2007 54.38 1990 54.24 9 2001 54.23 10 1953 54.18 11 1954 54.13 12 2005 54.08 13 1987 54.08

Rank Year oF 14 1986 54.0815 1939 54.0716 1938 54.0117 1981 53.8818 1991 53.8719 2003 53.8620 2000 53.8421 1946 53.8122 1933 53.8123 2002 53.76 24 2004 53.6225 1994 53.6126 1941 53.57

http://weather.about.com/od/climatechange/a/HottestYears_2.htm

0

20

40

60

80

100

2000s 1990s 1980s 1970s 1960s 1950s 1940s 1930s 1920s

Top 3 most unusual periods??Mexal Records

• November 28, 1976– Two days of -17oF preceded by mild month– Lots of winter damage

• Summer 1980– Broke most records for daily high T in summer– Killed hundreds of people / millions of trees– Did not make the Top 26 hottest

• Summer 1994– Broke records set in 1980!!!– Only 25th hottest year on record!!!

• Summer 2006– El Paso, TX -- Rio Grande overflows its banks

There will be less water?Science Findings Issue 97/ Oct ‘07

1999 2015 2031 2047 2063 2079 2095

Year

-100

-60

-80

-40

-20

0

20

Central Rocky Mountains Pacific Northwest Southern Rocky Mountains Sierra Nevada

Issues

• It’s gonna get hotter!!

• It’s gonna get drier!!

• Greater temperature fluctuations

• CO2 increase from 385 ppm in 2007 to 450 ppm by 2050

• What’s it mean to me???

Piñon is moving up the hill/ after Ryerson 2006

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60

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100

6000 6500 7000 7500 8000 8500

Elevation (ft)

Piñon Mortality (%)Stocking (% Piñon )■,♦ = Northern

□, ◊ = Southwest (wh)

□, ◊ = Southcentral (gr)

Hardiness Zones are Changing/ Nat’l Arbor Day Foundation

http://www.arborday.org/media/zones.cfm

http://www.arborday.org/media/zones.cfm

Rule of Thumb

• A 1oF increase, increases ET by 1%

Water Use Will Increase Albuq. Jour. Jan 17, 2008

• A 1oF increase will increase water use by 1% (0.42”) – 11,405 gal/ac/yr– 21,019,019 gal/yr!!

• City has 1,843 irrigated acres – Parks & golf courses– Use 42”/ac/yr

Fire lines1%

Industrial1%

Institutional12%

Commercial29% Residential

57%

Water Use by Customer Class

Water Use Will Increase

• What happens if I don’t want to or can’t increase my water budget by 1%?– Decreased plant quality – Decrease green area– Accept more disease– Accept more mortality

Quality of life

Water Use by Trees /Craul p.216

y = 9.1167e0.0517x

R2 = 1

0

50

100

150

200

250

300

0 10 20 30 40 50 60 70Canopy Diameter (ft)

Water Use (gal/day)

Pecan Irrigation Requirements

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2

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12

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16

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Pecan-nonstressedPecan-maintenancePET (in)

Water (in/mo)

Afghan Pine Irrigation Requirements

0

2

4

6

8

10

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16

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Pine-nonstressedPine-maintenancePET (in)

Water (in/mo)

Las Cruces’ Tree Water Requirements

0

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60

80Non-stressedMaintenanceSurvival

Water Use (in/yr)

After Sammis & Jerigan 1992

Turf and Irrigation Affects Tilia cordata growth Stewart et al. HortSci 40(5):1529:2005

0

1

2

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Mulch Buffalo-NS Buffalo-S Kentucky-NS

Kentucky-S

LA 2000

LA 2001

*

* *

*

Leaf Area (m2)

Turf Treatment NS = not stressedS = stressed

0

2

4

6

8

Mulch Buffalo-NS Buffalo-S Kentucky-NS

Kentucky-S

Diameter (mm)

Rules of Thumb

• A 1oF increase, increases ET by 1%• To reduce water use—reduce canopy coverage

– Under nonstressed conditions, a full canopy uses the same amount of water, i.e. Kentucky bluegrass = pecan = mesquite, etc.

– Management issues: growing season, level of stress tolerance

• Rain is a good thing—don’t waste it! – Clean irrigation water (300 mg/L) adds about 1 ton of salt per

acre per year. Plants will use less than ½ of that.

Pest Outbreak Triangle/PNW,2000

“a condition of the plant body or of one of its parts that impairs normal functioning.”

Webster’s Dictionary

Definition of ‘Disease’

White Pine Blister Rust Spread

Sudden Oak Death

Joseph O'Brien

http://www.invasivespecies.gov

Oak sudden death = Phytophthora ramorum•84 susceptible species in US

•Calif. black oak•White fir•Calif. red fir•Coastal redwoods•Coast live oak•Douglas-fir•Madrone•Tanoak

•In 2005, spread to OR, WA, GA, LA, TN, SC•In 2006, found in 22 states

Eriophyid mites on ash and smoke tree

Ramon Sias 0.01”

http://cals.arizona.edu/maricopa/garden/html/t-tips/cultural/aleppo.htm

Aleppo Pine Blight (Coniferal chiggers)

Symptoms •Usually occur in the upper part of the tree in

December•Damage occurs several months earlier in the

hot, dry summer. •Needles turn grey then brown but continue to cling

to plump healthy branches until normal seasonal needle drop in the summer.

•Twigs and branches may die. •Water-soaked cankers can appear on branches,

which may split.

Aleppo Pine Blight on Afgahn pine? (Coniferal chiggers)

What are the critical parts of a tree?

Xylem

Bark

Cambium

What’s Killing Your Trees

Ash tree problems

‘90

‘93‘94

‘00‘03

‘90

‘93

‘80‘68

1994-itis in Raywood Ash

‘90

‘93

‘94

‘00

‘03

‘90

‘93

‘80‘68

Factors Affecting Acclimation-Tissue

• Tolerant• Pinus pinea

– Shoots = - 40oC– Roots = -10oC

• Intolerant• Eucalyptus

camaldulensis– Shoots = -10oC– Roots = - 3oC

Mesquite Freeze Damage / April 2003

What’s Killing Your Trees

Low Temperature Injury

J. Mexal

SW Injury

Ash

Pine

Willow

E. Shannon

Pecan

Global Warming Is Killing this Palm!

SW Injury Protection

E. Shannon