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Caulophyllum thalictroides

Common Name(s):

Phonetic Spelling
kaw-loh-FY-lum thal-ik-TROY-deez
This plant has low severity poison characteristics.
See below
Description

Blue Cohosh is a perennial herbaceous wildflower typically found in woodlands of oaks or maples where the native ground flora is still intact. Blue Cohosh is valued for its lacy, blue-green foliage and clusters of blue, fruit-like seeds. Leaves appear at mid-stem, blue in spring and turning bluish-green at maturity. Young plants are covered with a waxy bloom. Flowers give way in summer to attractive blue berry-like seeds (outer seed coating turns fleshy and blue as seeds mature) which resemble small grapes and provide ornamental interest into fall.

The genus name comes from the Greek words kaulos meaning a stem and phyllon meaning a leaf. The species name recognizes that the foliage is similar to meadow rue (Thalictrum).

Blue Cohosh prefers dappled sunlight and shady woodland with average moisture and fertile, slightly acidic, loamy soil containing organic matter from decaying leaves and other plant materials. The soil should be consistently moist and not dry out. The large seeds are difficult to germinate and the plant is slow to spread on its own, but it can be divided just after flowering. However, once it becomes established at a favorable site, Blue Cohosh is long-lived and established plants are generally best left undisturbed. It can also spread very slowly by rhizomes to form colonies.

Diseases, Insect Pests, and Other Plant Problems:

No known diseases or insect pests.

See this plant in the following landscape:
Cultivars / Varieties:
Tags:
#poisonous#NC native#flowering shrub#herbaceous perennials#attractive leaves#berries#foliage
 
Cultivars / Varieties:
Tags:
#poisonous#NC native#flowering shrub#herbaceous perennials#attractive leaves#berries#foliage
  • Attributes:
    Genus:
    Caulophyllum
    Species:
    thalictroides
    Family:
    Berberidaceae
    Life Cycle:
    Perennial
    Recommended Propagation Strategy:
    Division
    Seed
    Country Or Region Of Origin:
    Central and Eastern Canada to North Central Eastern United State
    Distribution:
    New Brunswick south to South Carolina, west to Arkansas and north to North Dakota and Manitoba.
    Wildlife Value:
    Pollen and nectar attract insects, foliage attracts caterpillars, and mice feed on the berries.
    Play Value:
    Wildlife Food Source
    Edibility:
    Seeds are toxic.
    Dimensions:
    Height: 1 ft. 0 in. - 2 ft. 0 in.
    Width: 0 ft. 6 in. - 1 ft. 0 in.
  • Whole Plant Traits:
    Plant Type:
    Native Plant
    Perennial
    Poisonous
    Woody Plant Leaf Characteristics:
    Deciduous
    Habit/Form:
    Ascending
    Erect
    Growth Rate:
    Slow
    Maintenance:
    Medium
  • Cultural Conditions:
    Light:
    Dappled Sunlight (Shade through upper canopy all day)
    Deep shade (Less than 2 hours to no direct sunlight)
    Partial Shade (Direct sunlight only part of the day, 2-6 hours)
    Soil Texture:
    High Organic Matter
    Loam (Silt)
    Sand
    Soil pH:
    Acid (<6.0)
    Alkaline (>8.0)
    Neutral (6.0-8.0)
    Soil Drainage:
    Good Drainage
    Moist
    NC Region:
    Mountains
    Piedmont
    USDA Plant Hardiness Zone:
    3b, 3a, 4b, 4a, 5b, 5a, 6a, 6b, 7b, 7a, 8b, 8a
  • Fruit:
    Fruit Color:
    Blue
    Gold/Yellow
    Green
    Fruit Value To Gardener:
    Showy
    Display/Harvest Time:
    Fall
    Fruit Type:
    Berry
    Fruit Length:
    < 1 inch
    Fruit Width:
    < 1 inch
    Fruit Description:
    After flowering, berry-like seeds appear, 1/3 of an inch across. These seeds are initially green, but they later become bright blue at maturity during the summer. The seed coat is fleshy. Because of the bright blue seed coats, woodland birds disperse the seeds, which are known to be toxic to humans.
  • Flowers:
    Flower Color:
    Gold/Yellow
    Green
    Flower Inflorescence:
    Panicle
    Flower Bloom Time:
    Spring
    Flower Shape:
    Radial
    Flower Petals:
    6 petals/rays
    Colored Sepals
    Flower Size:
    < 1 inch
    Flower Description:
    On a flowering plant, the central stem terminates in a round floral panicle about 1 to 3 inches long; each panicle has 5 to 30 flowers. Individual flowers are about 1/3 of an inch across, consisting of 6 petaloid sepals, insignificant petals, 6 stamens, and an ovoid ovary with a beak-like style. Underneath each flower, there are 3 to 4 green bractlets that resemble sepals. The blooming period occurs in spring before the leaves have fully developed.
  • Leaves:
    Woody Plant Leaf Characteristics:
    Deciduous
    Leaf Color:
    Green
    Leaf Value To Gardener:
    Showy
    Leaf Type:
    Compound (Pinnately , Bipinnately, Palmately)
    Leaf Arrangement:
    Alternate
    Leaf Shape:
    Oblong
    Obovate
    Ovate
    Leaf Margin:
    Entire
    Hairs Present:
    No
    Leaf Length:
    1-3 inches
    Leaf Width:
    1-3 inches
    Leaf Description:
    On a flowering plant, a compound leaf is located at the middle of the central stem, where it is divided into a whorl of 3 compound leaflets. Each leaflet is divided into 9 simple subleaflets arranged in groups of 3. The subleaflets are 1 to 3 inches long and ¾ to 2 inches across, broadly ovate-oblong to obovate-oblong, and smooth along their margins. The surface of the subleaflets is glabrous and green. The upper compound leaf of a flowering plant is located under the inflorescence. This compound leaf resembles the lower compound leaf, except its 3 compound leaflets are smaller in size.
  • Stem:
    Stem Color:
    Green
    Purple/Lavender
    Stem Is Aromatic:
    No
    Stem Form:
    Straight
    Stem Surface:
    Smooth (glabrous)
    Stem Description:
    Unbranched erect central stem is light green to pale purple, terete, glabrous, and often glaucous.
  • Landscape:
    Landscape Location:
    Naturalized Area
    Woodland
    Landscape Theme:
    Shade Garden
    Attracts:
    Bees
    Small Mammals
    Resistance To Challenges:
    Deer
    Problems:
    Contact Dermatitis
    Poisonous to Humans
  • Poisonous to Humans:
    Poison Severity:
    Low
    Poison Symptoms:
    Low level toxin if eaten. Can result in vomiting and diarrhea. If eaten in excess, can cause high blood pressure and symptoms similar to nicotine poisoning.
    Poison Toxic Principle:
    Alkaloids and saponins
    Causes Contact Dermatitis:
    Yes
    Poison Part:
    Roots
    Seeds