Helianthus annuus (wild)

Species category

Agricultural, Flower

Common name

common sunflower, sunflower, wild sunflower, annual sunflower

Diagnostic characters

Planting unit

AcheneAchene:
A dry, hard, one-chambered, one-seeded indehiscent fruit, as in buckwheat (Fagopyrum) or sunflower (Helianthus). The fruit wall is not united with the seed coat.

Shape

ObovateObovate:
Inverted egg shaped with apical end the broadest.

Size

  • Length 4–5 mm 
  • Width 2–3 mm 
  • Thickness 1–2 mm 

Color

Brown with various degrees of black stripes and/or blotches

Texture

PubescentPubescent:
Having hairs.
and smooth

Other structures

Small apicalApical:
The distal end of the fruit or seed away from the point of attachment or attachment scar.
collar

Identification notes

AchenesAchene:
A dry, hard, one-chambered, one-seeded indehiscent fruit, as in buckwheat (Fagopyrum) or sunflower (Helianthus). The fruit wall is not united with the seed coat.
obovate, compressed with a trace of an apicalApical:
The distal end of the fruit or seed away from the point of attachment or attachment scar.
collar. Color brown or dark gray with black mottling and an occasional black longitudinal line. Surface covered with appressedAppressed:
Pressed close or lying flat against something.
silky hairs, especially at the apicalApical:
The distal end of the fruit or seed away from the point of attachment or attachment scar.
end. AchenesAchene:
A dry, hard, one-chambered, one-seeded indehiscent fruit, as in buckwheat (Fagopyrum) or sunflower (Helianthus). The fruit wall is not united with the seed coat.
from ray flowers have lateral banding. Scar is basalBasal:
The base of the fruit or seed opposite the apical end.
.

Noxious weed seed categories

State Noxious Weed: Iowa 

AOSA examination list

Included

More information

For more information, see ISMA fact sheet.

Nomenclature

Family

Asteraceae

Valid name

Helianthus annuus L. (wild)

Synonyms

Helianthus annuus L. ssp. jaegeri (Heiser) Heiser
Helianthus annuus L. ssp. lenticularis (Douglas ex Lindl.) Cockerell
Helianthus annuus L. var. lenticularis (Douglas ex Lindl.) Steyerm.
Helianthus annuus L. var. macrocarpus (DC.) Cockerell
Helianthus annuus L. ssp. texanus Heiser
Helianthus annuus L. var. texanus (Heiser) Shinners
Helianthus aridus Rydb.
Helianthus lenticularis Douglas ex Lindl.

From Left to Right: 1.  Helianthus annuus  (cult.) 2.  Helianthus annuus  (wild) 3.  Helianthus petiolaris
From Left to Right: 1. Helianthus annuus (cult.) 2. Helianthus annuus (wild) 3. Helianthus petiolaris
 Helianthus annuus  (wild). Achenes with a small apical collar.
Helianthus annuus (wild). Achenes with a small apical collar.