Healthy Trees,

Healthy Cities

Phone App

Healthy Trees, Healthy Cities Healthy Trees, Healthy Cities

Creating a culture of stewardship that engages urban youth and community members in the planting, care, and stewardship of urban trees and forests to improve

the health of people and their communities

Apple and Android App Stores

“Healthy Trees Healthy Cities”

What does the app do?

The HTHC app has 5 modules:

1. Tree Stewardship

2. Pruning

3. Tree Health Monitoring

4. Early Pest Detection

5. Tree Planting

What is the information used for?

NATIONAL LOCAL PERSONAL

Year Trees Plots Trees/plot Miles Surveyed

2015 3646 58 62.8 29

2016 2084 35 59.5 17.5

New YorkYear Trees Plots Trees/plot Miles Surveyed

2015 2690 100 26.9 50

Philadelphia

Species # Trees

Honey Locust 902

London Plane Tree 634

Callery Pear 389

Ginkgo 347

Pin Oak 341

New YorkSpecies Found = 94

Species # Trees

London Plane Tree 343

Plum/Cherry 314

Norway Maple 206

Red Maple 191

Honey Locust 133

PhiladelphiaSpecies Found = 86

Most Common Species Most Common Species

2016: 7,000 Trees Surveyed w/ Casey Trees

Washington, D.C.

Summary

Sample Design

Early Signs

Later Signs

Tree 36

Stress Index -0.783

Tree 71

Stress Index -.409

Tree 45

Stress Index -0.191Tree 77

Stress Index 0.81

Tree 65

Stress Index 1.3

Tree 75

Stress Index -0.009

ത𝑋 (𝑧𝑣𝑖𝑔𝑜𝑟 + 𝑧𝐷𝑒𝑓𝑜𝑙 + 𝑧𝐷𝑖𝑒𝑏𝑎𝑐𝑘 + 𝑧𝑇𝑟𝑎𝑛𝑠𝑝𝑎𝑟𝑒𝑛𝑐𝑦 + 𝑧𝐷𝑖𝑠𝑐𝑜𝑙𝑜𝑟)

Tree Stress Index

Urban Tree Health Monitoring

Non-Stressor Specific Evaluation of Tree Health

Variable Notes

Discoloration Visual estimate

Defoliation Visual estimate

Transparency Digital estimate

Dieback Visual estimate

Crown Vigor Visual estimate

Red Maple

Healthy StressedStress Index

(n = 107)

(n = 191)

• Both cities show a similar range

in tree stress for red maple

street trees.

• 20% of red maples in both cities

have a stress index greater than

1.6.

Red Maple in

Philadelphia and New York

% o

f tr

ees m

easure

d

Honey locust

London plane

Red maple

40% of red maples have no fine twig

dieback while only 19% of honey locust

have 0% fine twig dieback.

Most trees regardless of

species have less than 30%

fine twig dieback.

Fine Twig Dieback

% o

f tr

ee

s m

ea

su

red

% Fine Twig Dieback

Healthy StressedStress Index

Transparency

Dieback

Discoloration

Defoliation

Results from a healthy

red maple.

Healthy StressedStress Index

Transparency

Dieback

Discoloration

Defoliation

Results from a

stressed red maple.

2D Graph 2

Stress Index

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5

% o

f tr

ees m

easure

d

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Zallscore vs Z_prob

Zallscore vs Z_prob

2D Graph 2

Stress Index

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5

% o

f tr

ee

s m

ea

su

red

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Zallscore vs Z_prob

Zallscore vs Z_prob

Healthy StressedStress Index

2D Graph 2

Stress Index

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5

% o

f tr

ee

s m

ea

su

red

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Zallscore vs Z_prob

Zallscore vs Z_prob London plane street trees (2015-2016).

2D Graph 2

Stress Index

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5

% o

f tr

ee

s m

ea

su

red

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Zallscore vs Z_prob

Zallscore vs Z_prob London plane street trees flooded during

hurricane Sandy. Measured 2 years post

Sandy (2014).

Example:Detecting new tree health issues.

QUESTIONS

Thank You!