Sundew – Drosera spp.

Overall At-Risk Score: 58

Latin Name:

Drosera spp.(L.) The species native to North America are Drosera anglica, Drosera brevifolia, Drosera cappilaris, Drosera filiformis, Drosera intermedia, Drosera linearis, and Drosera rotundfolia.

Common Name:

Sundews;

  • English Sundew, Great Sundew (D. angelica)
  • Dwarf Sundew, Small Sundew, Red Sundew (D. brevifolia)
  • Pink Sundew (D. capillaris)
  • Dewthread Sundew, Thread-leaved Sundew (D. filiformis)
  • Spoonleaf Sundew, Oblong-Leaved Sundew, Spatulate Leaved Sundew (D. intermedia)
  • Slenderleaf Sundew (D. linearis)
  • Common Sundew, Round-Leaved Sundew (D. rotundifolia)

Family:

Droseraceae (Sundew family)

Lifespan:

Perennial; can be long-lived, and most species will form thick clumps of clones.

Reproduction:

A stout flowering stock grows up from the basal leaves, topped with a cluster of small white-green flowers, which self pollinate when they close. These flowers produce many tiny seeds that are dispersed via wind, animal fur, and water. Each species of Drosera has different conditions that must be met for these seeds to germinate, typically needing environmental stimuli in the form of temperature and light or moisture levels.

Some plants can also reproduce asexually through fallen leaves.

Geographic Region:

  • English Sundew favors northern regions, but is sometimes able to acclimate itself to warmer climates. They can be found in every Canadian province and territory except Nova Scotia and Nunavut. They are also found in Alaska, California, Colorado, Idaho, Maine, Michigan, Minnesota, Montana, Oregon, Washington, Wisconsin, and Wyoming.
  • Dwarf Sundew is found mostly in the Southeast U.S., from Louisiana to the coast of the Atlantic and from Florida to Maryland.
  • Pink Sundew is found in Texas and the Southeastern states, from Louisiana to the coast of the Atlantic and from Florida to Virginia.
  • Dewthread Sundew lives in Alaska, California, Colorado, Idaho, Maine, Michigan, Minnesota, Montana, Oregon, Washington, Wisconsin, and Wyoming.
  • The Spoonleaf Sundews are native to Idaho, Texas, and all states east of the Mississippi River. They’re also found in the Canadian provinces of New Brunswick, Newfoundland, Labrador, Nova Scotia, Ontario, and Quebec and the territory Nunavut.
  • Slenderleaf Sundew is primarily found in Canada in the provinces of Alberta, Labrador, Manitoba, New Brunswick, Ontario, Quebec, and Saskatchewan. It can also be found in the Northwest Territories of Canada and the U.S. states of Michigan, Montana, and Wisconsin.
  • The Common Sundew can be found in almost every part of the U.S. and Canada, with the exception of the U.S. states of Arizona, Arkansas, Florida, Hawaii, Kansas, Louisiana, Missouri, Nebraska, Nevada, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming.

Habitat:

The species of Drosera native to North America are typically found in the temperate bogs of the eastern United States and Canada but can still be found in other parts of the continent. The one constant between all species of Sundews in North America is that they are all obligate wetland plants and rarely grow outside of a wetland ecosystem. They require constant wetness and can survive in soil with very low nutrient content.

Ability to Withstand Disturbance and Overharvest:

The ability of Drosera species to withstand disturbance has increased greatly in recent years due to the protections put on them by many states in the U.S. This has caused an increase in cultivating the plants in nurseries and greenhouses rather than wild harvesting.

Status of Endangered/Threatened (by state):

English Sundews are “Endangered” in Maine and Wisconsin and “Near Threatened” according to the IUCN Red List.
Dwarf Sundews are “Threatened” in Tennessee, “Endangered” in Kentucky, and not yet evaluated by the IUCN Red List.
Pink Sundews are “Endangered” in Maryland and Tennessee and not yet evaluated by the IUCN Red List.
Dewthread Sundews are “Special Concern” in Connecticut, “Rare” in New York, “Historical” in Rhode Island, and “Endangered” in Florida. They are of “Least Concern” globally, according to the IUCN Red List.
Spoonleaf Sundews are “Exploitably Vulnerable” in New York, “Threatened” in Florida and Illinois, “Rare” in Indiana, “Historical” in Kentucky, and “Endangered” in Ohio. They are “Near Threatened” according to the IUCN Red List.
Slenderleaf Sundews are “Threatened” in Wisconsin, “Endangered” in Maine, and of “Least Concern” globally, according to the IUCN Red List.
Common Sundews are “Exploitably Vulnerable” in New York, “Threatened” in Tennessee, and “Endangered” in Illinois and Iowa. They are of “Least Concern” globally, according to the IUCN Red List.

Part of Plant Used/Active Medicinal Compounds:

The roots, flowers, and seed capsules are frequently used in tea to treat breathing issues and break up chest congestion. Naphthoquinones are what gives the plant its antispasmodic effects.

Vulnerability of Habitat/Changes of Habitat Quality and Availability:

Drosera spp. are entirely reliant on bogs, fens, and other delicate wetland ecosystems; this makes their habitat incredibly sensitive and steadily shrinking. Though efforts are being made to preserve the wetlands in most parts of the U.S., much more work must be done to preserve their habitats.

Demand:

Sundew plants, much like the Venus Flytraps, are growing in popularity as ornamental plants in recent years due to their carnivorous nature. As a medicine, Sundew plants have begun being cultivated on a larger scale, or taken from places that don’t have as strict laws regulating them as the U.S. does, in an attempt to keep up with demand.

Wild Harvesting Impact On Other Species:

As obligate wetland plants, their natural ecosystems are already steadily on the decline due to human interference. Wild harvesting this plant, especially on a large scale, can cause a great disruption to the balance of the ecosystem around them.

Recommendations for Industrial and Home Use:

Many nurseries grow and sell large volumes of the easier to grow species of Sundew both to companies hoping to use them as medicine, as well as to home botanists trying to keep them as decoration. It is important to note that Sundews are rather delicate and temperamental and can be hard to keep alive without researching the optimal conditions to grow them in.

Citations