Seed Study - Helianthus annuus

Helianthus annuus - Annual Sunflower
Helianthus annuus - Annual Sunflower

NPS Photo

Species: Helianthus annuus
Common name: annual sunflower

Seedling Identification: Fairly large rounded cotyledons with large, pubescent true leaves.


Helianthus annuus – common sunflower
Average number of good seeds per gram bulk matter: 74
Average number of good seeds per gram cleaned: 1667
Commercial estimates of seeds per gram: n.a.
Percent seed: n.m.
Percent live: 62
Collection dates: September 9 and 15
Collection effort: 29 grams in 6 person hours.
Collection notes: Easy to collect if large amounts can be found. Seed tend to be damaged by insects so collect more than you think you will need.
Cleaning notes: Bulk seed measurement was off the receptacle (disk) but with lots of bracts. Cleaned seed was hard seeds only.

Last updated: January 23, 2018

Contact the Park

Mailing Address:

26611 US Highway 385
Hot Springs, SD 57747


(605) 745-4600

Contact Us