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Drosera intermedia Hayne

Spoon-leaved Sundew

Droseraceae (Sundew family)

Synonyms: Drosera longifolia Michx.; D. americana Willd.; D. intermedia var. americana DC.

General Description: Plants 5-20 cm tall, bearing leaves in a rosette or also at intervals for several centimeters along the stem. The ascending, spoon-shaped blades are about 4-5 mm wide, 8-20 mm long, and narrow to a long glabrous petiole 3-4 times as long as the blade. Long glandular hairs cover the upper leaf surfaces. Rosettes produce a single scape with up to 20 flowers. The corolla is white or tinged with pink and 5-8 mm long, and the sepals are up to about 5 mm long. The capsule is scarcely as long as the sepals. After the growing season, plants die back to an over-wintering bud.

Field Identification Tips: Drosera intermedia is a distinctive small, low-growing carnivorous plant. The basal rosette of leaves are covered by long, reddish, glandular hairs. A few white flowers occur on short stems, however, they bloom very early and the plants are most often found in fruit.

Phenology: June - August.

Similar Species: The leaves of D. rotundifolia are usually more spreading than ascending and more rotund in outline, generally being as broad as long. The leaves of D. anglica look more similar to D. intermedia, but have stipules adnate to the petiole except at the tip versus the stipules free nearly to the base for D. intermedia. In addition, the seeds of D. anglica are spindle-shaped and blackish, as opposed to the ellipsoid-obovoid, reddish-brown seeds of D. intermedia.

Habitat: Bogs, fens, and moist, acidic, sandy soils; often in standing water. Idaho populations occur in peatland habitats.

Global Distribution: North America, Europe, Asia Minor, and Cuba. Its main distribution in North America is between Minnesota and Newfoundland, south to eastern Texas and Florida, with isolated stations in Manitoba, Saskatchewan, British Columbia, and Idaho.

Idaho Distribution: Occurs in two separate areas in Idaho - the Selkirk Mountains in Boundary County, and the Sawtooth Valley in Custer County.

References:

Moseley, R. K., R. J. Bursik, F. W. Rabe, and L. D. Cazier. 1994. Peatlands of the Sawtooth Valley, Custer and Blaine Counties, Idaho. Cooperative Cost Share Project, Sawtooth National Forest, The Nature Conservancy, and Idaho Conservation Data Center, Idaho Department of Fish and Game. 64 pp. plus appendices.