Knautia arvensis (Field Scabious)

Plant Info
Also known as: Bluebuttons
Genus:Knautia
Family:Dipsacaceae (Teasel)
Life cycle:perennial
Origin:Europe
Status:
  • Weedy
Habitat:sun; average to dry disturbed soil; roadsides, fields, open woods, landscapes
Bloom season:June - September
Plant height:1 to 3 feet
Wetland Indicator Status:none
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: 4-petals Flower shape: indistinct Cluster type: flat Cluster type: round

[photo of flower] Numerous tiny flowers in dome-shaped flower heads 1 to 1½ inches across, at the tips of long, wiry, leafless stalks. Flowers are pink to lilac, 4-lobed, the flowers in the outer ring noticeably larger than those in the center of the head and the lobes of unequal size, one usually rather larger than the others. Protruding from the center of each flower are 4 violet-tipped stamens, which give the head a pincushion-like appearance. A short, hairy calyx surrounds each flower. The bracts around the base of the flower head are in 2 layers, leaf-like with long, white hairs around the edges.

Leaves and stems: Leaf attachment: basal Leaf attachment: opposite Leaf type: lobed Leaf type: simple

[photo of leaves] Leaves are basal and opposite but usually crowded on the lower stem. The lowest leaves are 3 to 8 inches long, stalked, and may be narrowly lance-elliptic and coarsely toothed, or divided with 3 to 6 narrow, toothless lobes on each side. Leaves are densely hairy and become smaller and stalkless as they ascend the stem.

[photo of hairy stem] Stems are multiple from the base, branched in the upper plant, densely hairy and green to purplish, commonly with purple spots.

Fruit: Fruit type: seed without plume

The flower head becomes a dome-shaped seed head; a hairy, angular seed about ¼ inch long develops below the calyx with the calyx eventually dropping off.

Notes:

Field Scabious is a garden escapee, introduced from Europe as an ornamental. It is a serious agricultural weed in some areas, noted as particularly aggressive in northwest British Columbia, where it has also been found invading high quality habitat. In Minnesota it hasn't made much of an impact yet, but time will tell. The flower heads somewhat resemble Wild Bergamot (Monarda fistulosa), which has unlobed leaves with serrated edges and flowers are more tubular in shape.

Please visit our sponsors

  • Minnesota Native Plant Society

Where to buy native seed and plants ↓

Map of native plant purveyors in the upper midwest

  • 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
  • Minnesota Native Landscapes - Your Ecological Problem Solvers

More photos

Photos courtesy Peter M. Dziuk taken on a roadside in Rice County and in a suburban garden in Ramsey 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.