Compass Plant       silphium laciniatum L.


Description: The Compass Plant is a warm-season perennial herb in the Compositae, or aster family. It reaches a height up to 3.5 meters.

 

Leaf: The sand-papery leaves are stiff and deeply lobed, resinous and tough. They are covered with short, stiff hairs and are mostly in a clump at ground level. Young plants and plants that are in the sun have edges usually pointed north and south. This characteristic helps save moisture and also tells the direction.

 

Flower: Two to three dozen yellow flowers, placed alternately and spirally around the stout, hairy stem, may open at once. Each head has both ray and disk flowers. The green bracts on the back of each head are in more than 2 series.

 

Blooming months: July-September

 

 

 

 

8-20

10-13

6-23

 

Discussion: The deep, thick taproots of the compass plant played an important role in the building the rich, black soil. Pioneers found that these plants, with their deep taproots, made plowing difficult, damaging plows and sometimes injuring draft animals. Compass Plant was important in the diet of bison, and it is eaten by cattle. From the upper stem of the compass plant, a clear sap may ooze out and can be firmed up with the finger. This makes a pleasant chewing gum with an odd, pine resin taste. Native American and pioneer children liked to chew it. Early Americans had many medicinal uses for the roots and leaves of the compass plant.

 

Distribution: This species is a common inhabitant of prairies. This Midwestern species ranges from Michigan to South Dakota, south to Texas and Mississippi.

 

Native or Introduced to Illinois: Native

 

Location: N41048.677’ W089040.972’

 

Copyright: © 2004 Nancy Trainor, Challand Middle School, Sterling, Illinois

                                ntrainor@sterlingschools.org

References:

Keller, Carolyn. Prairie Plants of Whiteside County, Whiteside IL County Natural Area Guardians, 1991.

Ladd, Doug. Tallgrass Prairie Wildflowers, The Nature Conservancy, 1995.

Peterson, Roger Tory. Wildflowers Northeastern/North Central North America, Houghton Mifflin Company, Boston, 1968.

Mohlenbroch, Robert H., and John W. Voigt. Prairie Plants of Illinois, Department of Conservation.

http://plants.usda.gov/

 

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