curlytop knotweed

(Persicaria lapathifolia)

Conservation Status
curlytop knotweed
 
  IUCN Red List

LC - Least Concern

     
  NatureServe

N5 - Secure

SNR - Unranked

     
  Minnesota

not listed

     
           
Wetland Indicator Status
     
  Great Plains

OBL - Obligate wetland

     
  Midwest

FACW - Facultative wetland

     
  Northcentral & Northeast

FACW - Facultative wetland

     
           
 
Description
 
 

Curlytop knotweed is a 24 to 60 tall, erect, annual forb that rises from a taproot and shallow, fibrous roots.

The stems are ascending to erect, occasionally branched, round, and hairless. They are conspicuously swollen at the leaf nodes.The Latin word polygonum is derived from Greek and means "many knees or joints", referring to the swollen nodes.

The leaves are alternate, variable in shape but usually lance-shaped, 1½ to 4¾ long, and 3 16 to 1½ wide. They are on leaf stalks up to long. The leaf stalks wrap around the stem with a membranous sheath (ocrea) at the base. The ocrea is hairless and does not have a fringe of hairs or bristles on the margin. It turns brown as the leaf matures and eventually peels away. The leaf blades are tapered or wedge-shaped at the base and taper to a point at the tip with concave sides along the tip. The upper surface is hairless. The lower surface is usually hairless, sometimes covered with short, soft, woolly hairs, especially when young. The margins are untoothed. There is sometimes a dark blotch in the middle of the leaf blade, but it is neither as common nor as prominent as with spotted lady’s thumb.

The inflorescence is an unbranched, spike-like cluster (raceme) at the end of the stem and branches and sometimes also rising from the upper leaf axils. The racemes are arching or nodding, robust, dense, 1¼ to 3 long, and 3 16 to ½ wide. They are usually not interrupted. The flowers are arranged in several bundles (fascicles) with 4 to 14 flowers each. The fascicles are sheathed at the base and the sheaths overlap.

Individual flowers are 1 16 to long. There are 5 sepals and no petals (5 tepals). The tepals are fused at the base. The outer 2 or 3 tepals are egg-shaped to elliptic, usually greenish-white, sometimes pink, with prominent, anchor-shaped veins. There are 5 or 6 stamens and 2 or 3 styles. The stamens have pink or red anthers. The styles are fused at the base. The flowers rarely open, so the stamens, styles, and inner tepals are difficult to see. There is no fragrance.

The fruit is dark brown to black, oval, 1 16 to wide achene. The achene is flattened or concave on both sides.

 
     
 

Height

 
 

24 to 60

 
     
 

Flower Color

 
 

Greenish-white to pink

 
     
 

Similar Species

 
 

Pennsylvania smartweed (Persicaria pensylvanica) racemes are mostly held erect, rarely nodding. The flowers are often pink.

Spotted lady’s thumb (Persicaria maculosa) is a smaller plant, no more than 32 in height. The ocrea has a few short hairs on the margin. There is usually a prominent, dark blotch in the middle of the leaf blade. The flowers are pink to rose.

 
     
 
Habitat
 
 

Wet to moist. Lake shores, pond edges, marshes, wet prairies, ditches, railroads, roadsides, gravel bars, disturbed sites. Full to partial sun.

 
     
 
Biology
 
 

Flowering

 
 

July to September

 
     
 
Use
 
 

 

 
     
 
Distribution
 
 

Distribution Map

 

Sources

2, 3, 4, 5, 7, 22, 24, 28, 29.

 
  7/27/2015      
         
 

Nativity

 
 

Native

 
         
 

Occurrence

 
 

Common

 
         
 
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 (flowering plants)  
  Superorder Asteranae  
 

Order

Solanales (nightshades, bindweeds, gooseweeds, and allies)  
 

Family

Polygonaceae (buckwheat)  
  Subfamily Polygonoideae  
  Tribe Persicarieae  
  Subtribe Persicariinae  
 

Genus

Persicaria (knotweeds, smartweeds, and waterpeppers)  
       
 

Subordinate Taxa

 
 

 

 
       
 

Synonyms

 
 

Persicaria incarnata

Persicaria tomentosa

Polygonum incanum

Polygonum incarnatum

Polygonum lapathifolium

Polygonum lapathifolium var. incanum

Polygonum lapathifolium var. nodosum

Polygonum lapathifolium var. ovatum

Polygonum lapathifolium ssp. pallidum

Polygonum lapathifolium var. prostratum

Polygonum lapathifolium var. salicifolium

Polygonum nodosum

Polygonum oneillii

Polygonum pensylvanicum ssp. oneillii

Polygonum scabrum

Polygonum tomentosum

 
       
 

Common Names

 
 

curltop ladysthumb

curlytop knotweed

curlytop smartweed

dock-leaf smartweed

dock-leaved smartweed

heart’s-ease

nodding smartweed

pale persicaria

pale smartweed

smartweed

willow weed

 
       

 

 

 

 

 

 

 

 

Glossary

Achene

A dry, one-chambered, single-seeded fruit, formed from a single carpel, with the seed attached to the membranous outer layer (wall) only by the seed stalk; the wall, formed entirely from the wall of the superior ovary, does not split open at maturity, but relies on decay or predation to release the contents.

 

Axil

The upper angle where a branch, stem, leaf stalk, or vein diverges.

 

Fascicle

A small bundle or cluster, often sheathed at the base, as with pine needles.

 

Node

The small swelling of the stem from which one or more leaves, branches, or buds originate.

 

Ocrea

A sheath around the stem at the base of a petiole formed from the stipules; a feature of many members of the Polygonaceae.

 

Petiole

The stalk of a leaf blade or compound leaf that attaches the leaf blade to the stem.

 

Raceme

An unbranched, elongated inflorescence with stalked flowers. The flowers mature from the bottom up.

 

Sepal

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

 

Sheath

The lower part of the leaf that surrounds the stem.

 

Stipule

A small, leaf-like, scale-like, glandular, or rarely spiny appendage found at the base of a leaf stalk, usually occurring in pairs and usually dropping soon.

 

Tepal

Refers to both the petals and the sepals of a flower when they are similar in appearance and difficult to tell apart. Tepals are common in lilies and tulips.

       
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Bill Reynolds
       
  curlytop knotweed    
       
MinnesotaSeasons.com Photos
   

Plant

  curlytop knotweed   curlytop knotweed
       
  curlytop knotweed    
       

Inflorescence

  curlytop knotweed   curlytop knotweed
       

Leaves

  curlytop knotweed   curlytop knotweed
       

Compare Pennsylvania smartweed on the left with curlytop knotweed on the right

  Pennsylvania smartweed    
       
       

 

Camera

     
Slideshows
   
  Pale Smartweed (Polygonum lapathifolium)
Bill Keim
 
  Pale Smartweed (Polygonum lapathifolium)  
     
  Persicaria lapathifolia (Nodding Smartweed)
Allen Chartier
 
  Persicaria lapathifolia (Nodding Smartweed) (  

 

slideshow

       
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Other Videos
 
  Pale Persicaria (Persicaria Lapathifolia L.) - 2012-09-02
W3stlander
 
   
 
About

Published on Sep 5, 2012

Pale Persicaria (Persicaria lapathifolia (L.) Delarbre, syn. Polygonum lapathifolium L.) is a plant of the family Polygonaceae. It is closely related to Redshank and as such is considered a weed in Britain and Europe.

Other common names for the plant include pale smartweed, curlytop knotweed, and willow weed.

-----------------
De beklierde duizendknoop (Persicaria lapathifolia, basioniem: Polygonum lapathifolium), knopige duizendknoop of Bleek knoopkruid is een algemeen voorkomende, eenjarige plant uit de duizendknoopfamilie (Polygonaceae).

   
       
  European Honeybee on Persicaria セイヨウミツバチ♀がオオイヌタデを訪花採餌
sigma1920HD
 
   
 
About

Published on Dec 26, 2014

Foraging workers of European honey bee (Apis mellifera, family Apidae) visiting pink flowers of (Persicaria lapathifolia, family Polygonaceae) for nectar and pollen. Mid-September 2014 in Japan.

日本語による詳細はブログをご覧下さい。
http://sigma-nature-vlog.blogspot.jp/2014/12/blog-post_44.html
オオイヌタデの花で採餌するセイヨウミツバチ♀

   
       
  Curlytop Knotweed, オオイヌタデ
Koji Kimura
 
   
 
About

Published on Sep 7, 2013

Curlytop Knotweed, オオイヌタデ

   
       

 

Camcorder

         
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Bill Reynolds
7/27/2015

Location: Pennington County

 

curlytop knotweed


     
     
 
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