Influence of Nutrition and Stress on

Sugar Maple at a Regional Scale

Scott W. Bailey Richard A. Hallett

Robert P. Long Stephen B. Horsley

Philip M. Wargo

USDA Forest Service, Northern Research Station

Sugar Maple Decline

• Scattered, episodic occurrences

• First documented in 1913

• Increasing frequency since 1960

• Throughout range (WI, ON, QC, VT, MA)

• Recent declines in northern Pennsylvania

Symptoms of Declines

• Reduced growth• Shoot and diameter• Shorter internodes produce tufted appearance

• Premature fall coloration

• Unusual levels of twig and branch dieback

• Individual trees showing these symptoms are randomly dispersed in the stand.

Decline Disease Characteristics

• Interaction of multiple causal factors• Abiotic and biotic factors• Gradual general deterioration, often ending in

death of trees• Often poorly understood

after Manion (1991) Tree Disease Concepts

Stress Factors

1. Predisposing factorsImbalanced Nutrition

Calcium

Magnesium

Manganese

(Aluminum)

Stress Factors

2. Inciting factors• Defoliating Insects• Drought• Soil Freezing• Winter Injury

3. Contributing factors• Fungi (esp. Armillaria)• Borers• Viral infections

Stress Factors

The Allegheny Problem

• 1994 survey showed 38,000 hectares with severe mortality on the Allegheny National Forest

• An additional 19,000 hectares with severe mortality were on state forests across the northern tier

• Sugar maple is the most severely impacted species with unusual mortality levels first noted in the early 1980’s

Dea

d B

asal

Are

a (%

)

0

5

10

15

20

25

30

35

unglac-up unglac-low glac-up glac-low

Vig

or

Cla

ss

0

1

2

3

Dead

Basal

Area

%

Vigor

Class

upper lower upper lowerunglaciated glaciated

1

2

30

10

20

30

Nit

rog

en

(%

)

0 .0

0 .5

1 .0

1 .5

2 .0

Ph

os

ph

oru

s (

%)

0 .0 0

0 .0 5

0 .1 0

0 .1 5P

ota

ss

ium

(%

)

0 .0

0 .3

0 .6

0 .9

Foliar N

%

P

K

0.3

0.6

0.05

0.10

1.0

2.0

0.9

0.15

upper lower upper lowerunglaciated glaciated

unglac-up unglac-low glac-up

Ca

lciu

m (

%)

0 .0

0.5

1.0

1.5

unglac-up unglac-low glac-up

Ma

gn

es

ium

(%

)

0 .00

0.05

0.10

0.15

Ma

ng

an

es

e (

%)

0 .0

0.1

0.2

0.3

Foliar Ca

%

Mg

Mn

upper lower upper lowerunglaciated glaciated

0

0.1

0.2

0

0.05

0.10

0

0.5

1.0

Insect Defoliation

•Between 1984 and 1996 eighty-six percent of the Allegheny National Forest received from 1 to 5

moderate to severe defoliations by:

Fall Cankerworm, elm spanworm, forest tent caterpillar, saddled prominent, gypsy

moth and pear thrips.

X Data

500 1000 1500

Y D

ata

0

10

20

30

40

50

60

severe

mild

defoliation

Dead

Map

le (

% B

asa

l A

rea)

Foliar Magnesium (%)

0

10

20

30

40

50

0.05 0.10 0.15

Vermont and New Hampshire Stands

• The additional stands were all glaciated and the till quality was variable.

• The range in nutrient status was similar to the stands in PA/NY.

• Generally lacked defoliation events during the past 20 years.

Foliar Nutrients

3300300

600900

12001500

18002100

24002700

3000

Calcium

Magnesium

PA/NY

NH/VT

20004300

66008900

1120013500

1580018100

2040022700

25000

PA/NY

NH/VT

5500 ppm

700 ppm?

?Will these low nutrient status stands that have NOT been

stressed have poorer health?

Sugar Maple Fine Twig Dieback vs.

Foliar Mg and Ca

Foliar Ca (ppm)

Su

gar

Map

le D

ieb

ack

Plateau - mild defoliationPlateau - severe defoliation

Foliar Mg (ppm)

Su

gar

Map

le D

ieb

ack

0 5000 10000 15000 20000 25000 300000%

5%

10%

15%

20%

25%

0 500 1000 1500 2000 2500 30000%

5%

10%

15%

20%

25%

Northern New England

Health Threshold

Health Threshold

De

ad

Su

ga

r M

ap

le B

as

al

Are

a

0%

5%

10%

15%

20%

25%

30%

35%

40%

NH/VTPA/NY

Low Defoliation Stress

High Defoliation Stress

High Mg High CaLow Mg Low Ca

Putting it all together: Stress, Ca, Mg, and Dead Sugar Maple

Defoliation stress does not impact SM mortality when nutrient thresholds are exceeded. In addition SM mortality is not effected in low nutrient status stands when defoliation stress is low. However when nutrient status is low AND trees are stressed, sugar maple mortality increases.

Fin

e T

wig

Die

ba

ck

0%

5%

10%

15%

NH/VTPA/NY

Low Defoliation Stress

High Defoliation Stress

High Mg High CaLow Mg Low Ca

Putting it all together: Stress, Ca, Mg, and Fine Twig Dieback

Fine twig dieback is a less severe health indicator than mortality.Again, adequate nutrients result in good health regardless of stress.However we see that poor nutrient status results in poorer health even when there is no defoliation stress.

Fin

e T

wig

Die

ba

ck

0%

5%

10%

15%

NH/VTPA/NY

Low Defoliation StressHigh Defoliation Stress

Low Mn High Mn

Putting it all together: Manganese Toxicity

De

ad

Su

ga

r M

ap

le B

as

al

Are

a

0%

5%

10%

15%

20%

25%

30%

35%

40%

NH/VTPA/NY

Low Defoliation StressHigh Defoliation Stress

High Mn

Low Mn

Low Mn Low Mn

High Mn

High Mn

High Manganese and high stress result in higher mortality and more fine twig dieback.

But again we see that even without defoliation stress, high Mn results in poorer health in NH/VT.

Although Mn is an essential nutrient, in high enough quantities it becomes toxic to sugar maple trees.

These data suggest that low Mg and Ca OR high Mn

AND

excessive stress (≥2 moderate – severe defoliations in 10 years)

are required for mortality to occur.

In addition poor nutrient status stands that have not been severely stressed are likely to be less healthy and are consideredto be at risk.

Sugar Maple Health: Regional Implications

Calcium2000

43006600

890011200

1350015800

1810020400

2270025000

PA/NY

NH/VT

5500 ppm

3300300

600900

12001500

18002100

24002700

3000

Magnesium

PA/NY

NH/VT

700 ppm

Growth and Health

Available Base Cations

-

Net Photosynthesis

-

Carbohydrate Supply

SecondaryStressors

+

+

+

Available Al

Available Mn

Acidification

-

-+

+

-

-

Conceptual Model

DefoliationDeep soil freezingDroughtAir pollutionRoot compactionArmillaria

Reduce chlorophyllReduce PhotosynthesisInterfere with carb transport

Acid rain also increases Al availability which along with Mn can have a negative impact on available Ca and Mg.

Summary•Overall, sugar maple health region-wide is good.

•However, decline syndrome is a concern range-wide.

•Tailoring management to site specific conditions can minimize occurrence of decline.

Recommendations

•Choosing appropriate sites for sugar maple culture.

•Examining nutrition.

•Monitoring stress events.

Managers can take positive steps to maintain the health of sugar maple by: