Drosera linearis (Linear-leaved Sundew)
Also known as: | Slender-leaf Sundew |
---|---|
Genus: | Drosera |
Family: | Droseraceae (Sundew) |
Life cycle: | perennial |
Origin: | native |
Status: |
|
Habitat: | sun; wet calcareous soils; fens of open peatlands, bogs |
Bloom season: | June - July |
Plant height: | 1 to 5 inches |
Wetland Indicator Status: | GP: none MW: OBL NCNE: OBL |
MN county distribution (click map to enlarge): | |
National distribution (click map to enlarge): |
Pick an image for a larger view. See the glossary for icon descriptions.
Detailed Information
Flower:
A one-sided raceme of 1 to 4 short-stalked flowers at the top of a slender naked stem to 5 inches tall. Flowers are ¼ to 3/8 inch across, with 5 rounded white petals, 5 yellow-tipped stamens and a single pistil with 5 split styles.
The 5 sepals are about half the length of the petals and sparsely and minutely gland-dotted, especially around the edge and near the base. The flowering stem is formed tightly coiled and unrolls as flowers mature and ascend.
Leaves and stems:
Leaves are basal, bright green, linear, straight to somewhat curled, 3/8 to 2½ inches long, up to about 1/8 inch (3mm) wide, the upper surface and edges covered with red, sticky-tipped glandular hairs that trap insects.
Leaf stalks are typically red, sometimes longer than the leaf blade, with an appendage (stipule) at the base that is 5 mm long, connected to the stalk for its entire length, and fringed along tip edge. Leaves are mostly erect to ascending, though some may be more spreading. Flowering stems (scapes) are erect, rise above the leaves, are green to red and smooth, though may be sparsely gland-dotted near the flowers.
Fruit:
Fruit is an oblong-elliptic capsule up to ¼ inch long and longer than the sepals. Inside are tiny black seeds less than 1 mm long with a pitted surface.
Notes:
There are 4 species of Drosera in Minnesota, plus 1 record of a hybrid (Drosera x obovata), all of which have more or less the same flower. The shape of the leaf blade is what distinguishes one species from another: Round-leaf Sundew (D. rotundifolia) has round blades, English Sundew (D. anglica) and Spoon-leaf Sundew (D. intermedia) have elliptic to spatula-shaped blades, while Linear-leaf Sundew leaves are linear, so proportionately much longer and narrower than the others. While some may confuse longer leaves of D. anglica for D. linearis (and there are numbers of misidentified images out there), once you see D. linearis you'll immediately know it, but the easy test is D. linearis leaves are much longer and always have straight, parallel sides right to the base where D. anglica sides are more rounded and tapered to the base. D. rotundifolia sometimes grows alongside D. linearis.
According to the DNR, in Minnesota, Linear-leaved sundew grows exclusively in a particular wetland habitat called patterned peat fens and, even there, only in open water tracks with cold ground water. While it was first collected in Minnesota way back in 1878 somewhere near Minneapolis (a record that is suspicious since there is no suitable habitat there), it wasn't found again for another century when the first botanical studies on Minnesota's vast northern peatlands were undertaken. Those surveys, by-and-large now complete, revealed that D. linearis is quite rare and notably the rarest of our four native sundews. Originally listed as Threatened in 1984, a better understanding of its habitat and its effective protection, it was reclassified as Special Concern in 1996. Still, its peatland habitat is extremely vulnerable to human activities, including peat mining and other activities that cause hydrology changes, even from miles away. D. linearis is currently listed as Threatened in Wisconsin.
Native Plant Nurseries, Restoration and Landscaping Services ↓
More photos
- Linear-leaved Sundew plant
- Linear-leaved Sundew plant
- Linear-leaved Sundew plant
- Linear-leaved Sundew plant
- Linear-leaved Sundew with Round-leaved Sundew
- Linear-leaved Sundew with Buckbean, Bladderwort and Rose Pogonia
- Linear-leaved Sundew peatland fen habitat
Photos by K. Chayka and Peter M. Dziuk taken in Lake County.
Comments
Have you seen this plant in Minnesota, or have any other comments about it?