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Giant Rattlesnake-plantain (Goodyera oblongifolia)

Life history

Species overview

Giant Rattlesnake-plantain (Goodyera oblongifolia), a Wisconsin Special Concern plant, is found in moist to dry hardwood or mixed hemlock-pine-hardwood forests, most commonly on the stabilized Nipissing beach ridges of the Apostle Islands. Blooming occurs throughout July; fruiting occurs throughout August. The optimal identification period for this species is early July through late August.

Synonyms: Goodyera oblongifolia var. reticulata, G. decipiens, Epipactis decipiens, Peramium decipiens


  • Distinguishing characteristics: Leaves typically white only in the midstrip, flowers larger than other species in this genus, which tend to be 2.5 to 5.5 mm long; largest leaves (4 to 6 cm) longer than in other Goodyera species (less than 4 cm).
  • Flower characteristics: Inflorescence a loose to often rather tight spiral; flowers greenish-white; lip 6 to 8 mm, with a deeply concave base tapering to a spreading or slightly recurved boat-shaped tip with involute or upright margins; anther acuminate, evidently surpassed by the 2.3 to 3.6 mm rostellar beak.
  • Fruit characteristics: Capsule erect, tapering on at least 1 end, pubescent, 1 cm long.
  • Leaf characteristics: Basal, narrowed to a broadly petiolar base; blades lance-ovate to narrowly elliptic, the largest 4 to 6 cm long, white along midstrip, seldom also on some of the other veins, but not strongly reticulately white-veined.


  • Blooming phenology: throughout July
  • Fruiting phenology: throughout August
  • Optimum time to identify: The optimal identification period for this species is early July through late August


  • Growth form: Forb-erect
  • Vegetative reproduction: Rhizomatous
  • Life cycle: Perennial
  • Comments: Associated Species: Abies balsamea, Thuja occidentalis, Tsuga canadensis, Acer rubrum, A. spicatum, Betula alleghaniensis, B. papyrifera, Cornus canadensis, Aralia nudicaulis, Lycopodium spp., Clintonia borealis, Maianthemum canadense.

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 Giant Rattlesnake-plantain (Goodyera oblongifolia). 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 Goodyera oblongifolia in the Natural Heritage Inventory Database as of July 2015.

Summary Information
State StatusSC
Federal Status in Wisconsinnone
State RankS1
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 moist to dry hardwood or mixed hemlock-pine-hardwood forests, most commonly on the stabilized Nipissing beach ridges of the Apostle Islands.
  • Soils: Rich or sandy soils.

Natural communities

This table lists the natural communities that are associated with Giant Rattlesnake-plantain. 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).

Ecological landscapes

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

Map of the Ecological Landscapes of Wisconsin.

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 site preparation that heavily disturbs herbaceous ground layer and soil; these include bulldozing and furrowing, as well as grubbing and stump removal.
  • 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 broadcast spraying of herbicides; use care with spot spraying.

Management guidance

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

  • Maintain structural characteristics of old growth forests such as downed logs and other coarse woody debris.
  • Maintain high forest canopy cover; this species requires shaded habitat conditions.


Giant Rattlesnake-plantain Photo.

Photo by Drew Feldkirchner, Wisconsin DNR.

Giant Rattlesnake-plantain Photo.

Photo by Drew Feldkirchner, Wisconsin DNR.

Giant Rattlesnake-plantain Photo.

Photo © Marisa Lee.

Giant Rattlesnake-plantain Photo.

Photo © Marisa Lee.

Giant Rattlesnake-plantain Photo.

Photo by Kevin Doyle, Wisconsin DNR.

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