American Sycamore

Platanus occidentalis

Platanaceae · broadleaf deciduous tree · introduced

Last updated April 25, 2026

Plant Profile

Size & Form

Height

100 ft

Spread

98 ft

Growth Rate

Fast

Size at 20 yr

65 ft

Lifespan

Long-lived

Site Requirements

Light

Sun to Part Shade

Soil Drainage

Wet Tolerant

Soil pH

4.9-6.5

Water

High

Drought Tolerance

Low

Hardiness

Zones 4a–8b

Ornamental Interest

Bloom Time

April

Fall Color

Brown, yellow

Origin

from Maine to Ontario and Minnesota and south to Florida

Powdery MildewHigh

Active Conidial Spread

AphidHigh

Peak Population & Dispersal

Fall webwormHigh

Larval Feeding & Web Building

Anthracnose (Shade Trees)Moderate

Active Infection & Secondary Spread

Diseases: Regionally Documented (2)

Discula destructiva (dogwood), Kabatiella and Discula spp... Anthracnose Multiple obligate biotrophic fungi (Erysiphales: Erysipha... Powdery Mildew

Pests: Regionally Documented (3)

Aphidoidea Aphid Hyphantria cunea Fall webworm Stomacoccus platani Sycamore scale

Phenological Calendar

View full calendar (8 stages)

Stage	Typical Window	What to Look For
Bud break BBCH 07	Feb 15-Mar 15	Buds swelling and beginning to open; first green tissue visible
Leaf emergence BBCH 11	Mar 1-Apr 1	First leaves fully unfurled on new growth
Bloom start BBCH 61	Mar 15-May 15	First open flowers visible; flowers red
Bloom end / petal fall BBCH 69	Apr 15-May 31	Last petals falling; flower structures fading
Fruit/seed development BBCH 71	Jun 1-Aug 31	Fruit or seed structures forming; fruit color: brown
Fruit/seed maturity BBCH 85	Sep 1-Nov 30	Fruit fully colored and ripened; seed dispersal may begin
Fall color / leaf senescence BBCH 93	Oct 1-Nov 15	Leaves changing color; fall display beginning
Dormancy BBCH 97	Nov 15-Feb 28	Leafless; no active growth; dormant buds set

Data Maturity

Structured Multiple sources. Expert review underway.