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Clustered Broomrape (Orobanche fasciculata)

Life history

Species overview

Clustered Broomrape (Orobanche fasciculata), a Wisconsin Threatened plant, is found in dry prairies and dunes (both near Lake Michigan and inland). Blooming occurs throughout June; fruiting occurs throughout July. The optimal identification period for this species is throughout June.

Synonyms: Anoplanthus fasciculatus, Phelypaea lutea, Thalesia fasciculata, Thalesia lutea, Orobanche fasciculata var. franciscana, Orobanche fasciculata var. lutea


  • Distinguishing characteristics: 4 to 10 pedicels, slightly if at all longer than the stem.
  • Flower characteristics: Loose, flat-topped corymb that surpasses the stem; bractlets absent; corolla 1.5 to 3 cm; calyx lobes about equal to the tube.
  • Fruit characteristics:
  • Leaf characteristics: Reduced to scales, ovate, hairy, all or at least the upper with an abrupt, sharp point.


  • Blooming phenology: throughout June
  • Fruiting phenology: throughout July
  • Optimum time to identify: The optimal identification period for this species is throughout June


  • Growth form: Forb-erect
  • Vegetative reproduction:
  • Life cycle: Annual
  • Comments: Associated Species: Ammophila breviligulata, Artemisia campestris, Cirsium pitcheri. Root-parasite herb.

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 Clustered Broomrape (Orobanche fasciculata). 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 Orobanche fasciculata in the Natural Heritage Inventory Database as of July 2015.

Summary Information
State StatusTHR
Federal Status in Wisconsinnone
State RankS1
Global RankG4G5
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 dry prairies and dunes (both near Lake Michigan and inland).
  • Soils: Dry, sandy soils.

Natural communities

This table lists the natural communities that are associated with Clustered Broomrape. 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
Great Lakes Dune 3
Dry Prairie 2
Sand Prairie 2

Ecological landscapes

This table lists the ecological landscape association scores for Clustered Broomrape. 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 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).
  • Maintain and restore open habitat through selective clearing and brushing.
  • Avoid disturbance to shorelines and the forest-beach interface.


Clustered Broomrape Photo.

Clustered broomrape is a root parasite and habitat specialist in dunes along Lake Michigan.

Photo © R.C. Moran.

Clustered Broomrape Photo.

Photo by  staff, Wisconsin DNR.

Clustered Broomrape Photo.

Photo © Robert H. Read.

Clustered Broomrape Photo.

Photo © John van der Linden.

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