General Plant Information (Edit)
Plant Habit: Herb/Forb
Life cycle: Perennial
Sun Requirements: Full Sun
Water Preferences: Mesic
Soil pH Preferences: Slightly acid (6.1 – 6.5)
Neutral (6.6 – 7.3)
Minimum cold hardiness: Zone 3 -40 °C (-40 °F) to -37.2 °C (-35)
Maximum recommended zone: Zone 8b
Plant Height: 36 - 100 inches
Plant Spread: 36 - 48 inches
Leaves: Other: basal leaves up to 1 foot long
Fruit: Edible to birds
Flowers: Showy
Flower Color: Yellow
Bloom Size: 1"-2"
Flower Time: Summer
Late summer or early fall
Underground structures: Taproot
Uses: Will Naturalize
Edible Parts: Fruit
Wildlife Attractant: Bees
Propagation: Seeds: Stratify seeds: 3 months at 40 degrees
Pollinators: Various insects
Containers: Not suitable for containers
Miscellaneous: Tolerates poor soil
Conservation status: Least Concern (LC)

Conservation status:
Conservation status: Least Concern
Common names
  • Compass Plant
  • Compassplant
  • Polarplant
  • Turpentine Plant
  • Gum Weed
  • Cut-leaf Silphium
  • Pilot Weed
Botanical names
  • Accepted: Silphium laciniatum
  • Synonym: Silphium laciniatum var. robinsonii
  • Synonym: Silphium laciniatum var. laciniatum

  • Posted by ILPARW (southeast Pennsylvania - Zone 6b) on Feb 17, 2018 8:43 PM concerning plant:
    This very tall perennial gets its name from the thick, sharply lobed leaves orienting themselves in a north-south direction. it is slow growing and very long lived. Big plants can have up to 100 flowers. It is a major prairie plant in a native range from North Dakota & Minnesota through Michigan and then southward into the deep South and even a little into New Mexico. The Lurie Garden in downtown Chicago has some spread around in their huge naturalistic garden. This is sold by many native plant nurseries for prairie restorations and for naturalistic native plant landscapes.
  • Posted by jmorth (central Illinois) on Dec 26, 2011 1:18 PM concerning plant:
    The deeply cut large basal leaves are commonly oriented in the N - S direction, hence the name. A common Illinois wildflower partial to prairie habitats and along RR right of ways.
    Stem leaves are smaller alternate and tend to clasp the stem. Flower heads are up to 4.5" across w/ 20 to 30 petal-like ray flowers around a central yellow disk.
    Omaha and Ponca Indians were reluctant to camp near these plants because they thought the plant attracted lightning. They sometimes burned the plant's dried roots during heavy electrical storm manifestation thinking it a charm against lightning strike.
    Root thought to alleviate head colds and head pains by some tribes and early settlers. Dried leaves used to treat dry, persistent coughs and intermittent fevers.

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