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Brittle Prickly-pear (Opuntia fragilis)

Life history

Species overview

Brittle Prickly-pear (Opuntia fragilis), a Wisconsin Threatened plant, is found in thin, dry soil over rock, as well as sand prairies. Blooming occurs early June through late July; fruiting occurs early July through late August. This species can be identified year-round.

Synonyms: Cactus fragilis, Opuntia fragilis var. denudata, Opuntia schweriniana


  • Distinguishing characteristics: Pads round, not flattened in cross section, joints turgid, easily detatched, 2 to 5 cm.
  • Flower characteristics: Yellow to greenish, 4 to 5 cm wide.
  • Fruit characteristics: Fleshy and greenish to reddish when young, dry and tan at maturity, inedible, 1.2 to 1.5 cm; seeds discoid, with an irregular margin.
  • Leaf characteristics: Strongly barbed spines, 1.2 to 2.5 cm.


  • Blooming phenology: early June through late July
  • Fruiting phenology: early July through late August
  • Optimum time to identify: This species can be identified year-round


  • Growth form: Shrub
  • Vegetative reproduction:
  • Life cycle: Perennial
  • Comments: Associated Species: Quercus macrocarpa, Q. velutina, Selaginella rupestris, Juniperus virginiana, Rhus glabra.

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 Brittle Prickly-pear (Opuntia fragilis). 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 Opuntia fragilis in the Natural Heritage Inventory Database as of July 2015.

Summary Information
State StatusTHR
Federal Status in Wisconsinnone
State RankS3
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 thin, dry soil over rock, as well as sand prairies.
  • Soils: Dry soils.

Natural communities

This table lists the natural communities that are associated with Brittle Prickly-pear. 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 Brittle Prickly-pear. 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 locating landings, staging areas, or access routes in open sandy areas dominated by native grasses.
  • 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.

Management guidance

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

  • Prescribed burns and/or brushing may be beneficial (dependent on local site conditions).
  • Follow BMPs, especially around streams and use care near ravines, steep slopes, cliffs, rock outcrops, etc.


Brittle Prickly-pear Photo.

Opuntia fragilis. Photo from Endangered Resources files.

Photo by  staff, Wisconsin DNR.

Brittle Prickly-pear Photo.

Photo by Thomas Meyer, Wisconsin DNR.

Brittle Prickly-pear Photo.

The brittle prickly pear is a rare habitat specialist known from several Bedrock Glades in the Central Sand Hills.

Photo by  staff, Wisconsin DNR.

Brittle Prickly-pear Photo.

Photo © Tyler Brandt.

Brittle Prickly-pear Photo.

Photo © Tyler Brandt.

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