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Kevin Doyle

Hazel Dodder (Cuscuta coryli)

Life history

Species overview

Hazel Dodder (Cuscuta coryli), a Wisconsin Special Concern plant, is found in sandy lake margins, wet-mesic areas, mud flats and moist fields, and in one instance, a prairie. Blooming occurs from July through September. The optimal identification period for this species is July through September.

Synonyms: Grammica coryli, Cuscuta compacta var. crenulata, Cuscuta crenulata, Cuscuta inflexa, Epithymum coryli


  • Distinguishing characteristics: Distinguished from C. indecora by its 4-parted smaller flowers.
  • Flower characteristics: Yellowish white, mostly 4-parted, 1 to 2 mm.
  • Fruit characteristics: Capsule, seed 1.5 mm long.
  • Leaf characteristics: Alternate, minute scales in place of leaves.


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


  • Growth form: Vine-herbaceous
  • Vegetative reproduction:
  • Life cycle: Annual
  • Comments: In Wisconsin, noted to be parasitic on Corylus, Agalinis, Asclepias syriaca, Helianthus, Solidago canadensis, and members of the Lamiaceae family. In Michigan, known to parisitize Mentha, Euthamia, Aster, Stachys, Ceonothus, Amphicarpeaea, Bidens, Mondarda, and Symphoricarpos.

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 Hazel Dodder (Cuscuta coryli). 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 Cuscuta coryli 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 sandy lake margins, wet-mesic areas, mud flats and moist fields, and in one instance, a prairie.
  • Soils: Sandy to mucky soils.

Natural communities

This table lists the natural communities that are associated with Hazel Dodder. 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 Hazel Dodder. 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.

  • No avoidance measures have been developed for this species.

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.
  • Maintain partial canopy to encourage woodland species; avoid closed-canopy conditions.
  • Avoid disturbance to shorelines and the forest-beach interface.


Hazel Dodder Photo.

Photo ©  USDA-NRCS.

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