Drosera linearis (Linear-leaved Sundew)

Plant Info
Also known as: Slender-leaf Sundew
Genus:Drosera
Family:Droseraceae (Sundew)
Life cycle:perennial
Origin:native
Status:
  • State Special Concern
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):Minnesota county distribution map
National distribution (click map to enlarge):National distribution map

Pick an image for a larger view. See the glossary for icon descriptions.

Detailed Information

Flower: Flower shape: 5-petals Cluster type: raceme

[photo of flower just opening up] 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.

[photo of sepals with minute glands] 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: Leaf attachment: basal Leaf type: simple

[photo of leaves] 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.

[photo of leaf stalks] 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 type: capsule/pod

[photo of developing 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.

Please visit our sponsors

  • Wild Ones Twin Cities Chapter

Where to buy native seed and plants ↓

Map of native plant purveyors in the upper midwest

  • Itasca Ladyslipper Farm - Native orchids, container grown
  • Prairie Restorations - Bringing people together with the land
  • Shop for native seeds and plants at PrairieMoon.com!
  • Shooting Star Native Seeds - Native Prairie Grass and Wildflower Seeds
  • Morning Sky Greenery - Native Prairie Plants

More photos

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?

Post a comment

Note: All comments are moderated before posting to keep the riff-raff out. An email address is required, but will not be posted—it will only be used for information exchange between the 2 of us (if needed) and will never be given to a 3rd party without your express permission.

For info on subjects other than plant identification (gardening, invasive species control, edible plants, etc.), please check the links and invasive species pages for additional resources.



(required)




Note: Comments or information about plants outside of Minnesota and neighboring states may not be posted because Id like to keep the focus of this web site centered on Minnesota. Thanks for your understanding.