blue cohosh

(Caulophyllum thalictroides)

Conservation Status
blue cohosh
  IUCN Red List

not listed

     
  NatureServe

N4N5 - Apparently Secure to Secure

SNR - Unranked

     
  Minnesota

not listed

     
           
           
 
Description
 
 

Blue cohosh is a 1 to 3 tall, erect, perennial forb that rises on multiple stems from a rhizome.

The stems are erect, hairless, and unbranched. They bear just 2 leaves, the first just above the middle, the second just below the inflorescence.

The first leaf is compound, triternate, and stalkless. It divides at the base into 3 long stalks. Each stalk is again divided into 3 shorter stalks. At the end of each of these shorter stalks are 3 leaflets. The overall appearance is of 3 biternate leaves. The 27 leaflets are broad, inversely egg-shaped, 2 to 3 long, and ¾ to 4 wide. They are usually 2- to 5-lobed near the tip, but they may be unlobed. When young they are covered with a whitish, waxy coating. The margins are untoothed. The upper and lower surfaces are hairless. The second leaf is similar to the first but smaller.

The inflorescence is a small, branched cluster of 5 to 70 flowers at the end of the stem.

The flowers are to ½ wide. There are 3 or 4 sepal-like bracts that drop early. There are 6 petal-like, yellowish green, widely spreading sepals. The 6 petals are reduced to gland-like nectaries, are opposite the sepals, and are much shorter than the sepals. In the center of the flower are 6 stamens with yellow anthers surrounding a green ovary.

The fruits never develop. Two large growing seeds rupture the ovary. The seeds are borne naked in pairs on short stems at the end of the elongated pedicel above the leaves. The seeds are have a dark blue, fleshy seed coat. The seed coat is covered with a whitish, waxy coating, making the seed appear light blue.

 
     
 

Height

 
 

1 to 3

 
     
 

Flower Color

 
 

Yellowish green

 
     
 

Similar Species

 
 

May-apple (Podophyllum peltatum) leaves are not compound. The flower droops from the axil of two leaves. The fruit is a yellow berry.

Twinleaf (Jeffersonia diphylla) leaves are divided into 2 kidney-shaped segments. The flowers are borne on a leafless flower stalk. The fruit is brownish and capsule-like.

 
     
 
Habitat
 
 

Moist. Woods.

 
     
 
Biology
 
 

Flowering

 
 

April to May

 
     
 
Use
 
 

 

 
     
 
Distribution
 
 

Distribution Map

 

Sources

2, 3, 4, 5, 7, 28.

 
  1/4/2014      
         
 

Nativity

 
 

Native

 
         
 

Occurrence

 
 

 

 
         
 
Taxonomy
 
  Kingdom Plantae (green algae and land plants)  
  Subkingdom Viridiplantae (green plants)  
  Infrakingdom Streptophyta (land plants and green algae)  
  Superdivision Embryophyta (land plants)  
  Division Tracheophyta (vascular plants)  
  Subdivision Spermatophytina (seed plants)  
  Class Magnoliopsida (dicots)  
  Superorder Ranunculanae  
 

Order

Ranunculales  
 

Family

Berberidaceae (barberry)  
  Subfamily Berberidoideae  
  Tribe Leonticeae  
 

Genus

Caulophyllum (blue cohosh)  
       
 

Subordinate Taxa

 
 

 

 
       
 

Synonyms

 
 

 

 
       
 

Common Names

 
 

blue cohosh

papooseroot

papoose-root

squawroot

squaw-root

 
       

 

 

 

 

 

Glossary

Biternate

Twice ternate. A leaf divided into 3 segments, with each segment divided into 3 leaflets.

 

Bract

Modified leaf at the base of a flower stalk, flower cluster, or inflorescence.

 

Compound leaf

A leaf that is divided into leaflets, each leaflet having the general appearance of a leaf, with all leaflets attached to a single leaf stem.

 

Nectary

A tissue or organ which produces nectar, usually at or near the base of the inside of a flower.

 

Pedicel

On plants: the stalk of a single flower in a cluster of flowers. On Hymenoptera and Araneae: the narrow stalk connecting the thorax to the abdomen.

 

Rhizome

A horizontal, usually underground stem. It serves as a reproductive structure, producing roots below and shoots above at the nodes.

 

Sepal

An outer floral leaf, usually green but sometimes colored, at the base of a flower.

 

Triternate

Three times ternate. A leaf divided into 3 main divisions, with each division divided into 3 segments, and each segment divided into 3 leaflets.

       
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MinnesotaSeasons.com Photos
   

Plant

  blue cohosh   blue cohosh
       
  blue cohosh    
       

Inflorescence

  blue cohosh   blue cohosh
       
  blue cohosh    
       

Leaves

  blue cohosh   blue cohosh
       
  blue cohosh   blue cohosh
       

Infructescence

  blue cohosh    
       
       

 

Camera

     
Slideshows
   
  Blue Cohosh
DianesDigitals
 
  Blue Cohosh  
 
About

Copyright DianesDigitals

 
     
  Blue Cohosh (Caulophyllum thalictroides)
Andree Reno Sanborn
 
  Blue Cohosh (Caulophyllum thalictroides)  

 

slideshow

       
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Other Videos
 
  lue Cohosh
wvoutdoorman
 
   
 
About

Published on Mar 24, 2012

Blue Cohosh

   
       
  An Herb Tip
SeraphSeeker
 
   
 
About

Published on Jul 23, 2013

Brett stops to talk about Blue Cohosh.

   
       

 

Camcorder


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