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Sycamore (Platanus occidentalis)

Life history

Species overview

Sycamore (Platanus occidentalis), a Wisconsin Special Concern plant, is found in floodplain forests. Blooming occurs throughout May; fruiting occurs early June through early September. This species can be identified year-round.

Synonyms: Platanus glabrata, Platanus occidentalis f. attenuata, Platanus occidentalis var. glabrata


  • Distinguishing characteristics: Although sycamore leaves may be similar to those of various maple species (Acer spp.), the former have shallower lobes and are arranged alternately instead of oppositely.
  • Flower characteristics: Flowers very small, solitary, with long stems.
  • Fruit characteristics: Achenes many on spherical receptacles; seeds of sun flower-like; seed pod 7 to 8 mm in length and with hairs below the pod that are nearly as long as the pod itself.
  • Leaf characteristics: Alternate, broadly 3- to 5-lobed, sharply toothed and mostly kidney-shaped in outline.


  • Blooming phenology: throughout May
  • Fruiting phenology: early June through early September
  • Optimum time to identify: This species can be identified year-round


  • Growth form: Tree
  • Vegetative reproduction:
  • Life cycle: Perennial
  • Comments: Associated Species: Acer saccharinum, Betula nigra, Ulmus americana, Celtis occidentalis, Fraxinus pennsylvanica, Gleditsia triacanthos, Crataegus spp.

State status

Status and Natural Heritage Inventory documented occurrences in Wisconsin

The table below provides information about the protected status - state and federal - and the rank (S and G Ranks) for Sycamore (Platanus occidentalis). See the Working List Key for more information about abbreviations. Counties shaded blue have documented occurrences for this species in the Wisconsin Natural Heritage Inventory database. The map is provided as a general reference of where this species has been found to date and is not meant as a range map.

Documented locations of Platanus occidentalis in the Natural Heritage Inventory Database as of July 2015.

Summary Information
State StatusSC
Federal Status in Wisconsinnone
State RankS2
Global RankG5
Tracked by NHIY

Habitats and landscapes

The Natural Heritage Inventory has developed scores indicating the degree to which each of Wisconsin's rare plant species is associated with a particular natural community or ecological landscape. This information is similar to that found in the Wildlife Action Plan for animals. As this is a work in progress, we welcome your suggestions and feedback.

General habitat information

  • Habitat description: Found in floodplain forests.
  • Soils: Moist to wet, alluvial soils.

Natural communities

This table lists the natural communities that are associated with Sycamore. Scores for natural community associations are: "significant" association (score=3), "moderate association" (score=2) or the species can be present but is only weakly associated with the community (score=1).

Natural communities score
Floodplain Forest 3

Ecological landscapes

This table lists the ecological landscape association scores for Sycamore. The scores (3=High, 2=Moderate, 1=Low, 0=None) also correspond to the map.

Map of the Ecological Landscapes of Wisconsin.

Ecological landscape score
Southeast Glacial Plains 3
Western Coulee and Ridges 3

Species guidance

The Endangered Resources Program has developed avoidance measures and management guidelines for plants on the Natural Heritage Working List. These are a work in progress, and we welcome your suggestions and feedback. Sources used in developing this information can be found here.

Avoidance measures

These are specific actions designed to avoid "take" (mortality) of this species.

  • Avoid broadcast spraying of herbicides; use care with spot spraying.
  • Avoid known individual plant locations and conduct operations elsewhere when they are least likely to cause damage. Ideally, this would involve frozen, snow-covered ground. However, in areas of the state where frozen conditions are unreliable, very dry soils late in the growing season might be the best available alternative. Consult with a biologist, if needed.
  • Avoid site preparation that heavily disturbs herbaceous ground layer and soil; these include bulldozing and furrowing, as well as grubbing and stump removal.
  • Avoid locating landings, staging areas, or access routes on or near known populations.

Management guidance

Management guidelines are additional considerations that may help maintain or enhance habitat for this species

  • Minimize disturbance to hydrology, including soil disturbance from rutting.


Sycamore Photo.

Photo © Kitty Kohout.

Sycamore Photo.

Photo © Kitty Kohout.

Sycamore Photo.

Photo © Kitty Kohout.

Sycamore Photo.

Photo © Kitty Kohout.

Sycamore Photo.

Bark of Platanus occidentalis

Photo © Suzan Campbell.

Support for Wisconsin's rare plant information has been provided by the Division of Forestry, the Endangered Resources Fund and the Wisconsin Rare Plant Preservation Fund. To donate, visit the Natural Resources Foundation of Wisconsin [exit DNR].

Last revised: Wednesday, May 05, 2021
Southwest Savanna Southern Lake Michigan Coastal Western Coulees and Ridges Southeast Glacial Plains Central Sand Hills Central Lake Michigan Coastal Central Sand Plains Northern Lake Michigan Coastal Northern Lake Michigan Coastal Northeast Sands Western Prairie North Central Forest Northern Highlands Northwest Lowlands Northwest Sands Northwest Lowlands Superior Coastal Plains Forest Transition