Family
Asteraceae
Distribution in Canada
Found in BC
Duration of life cycle
Annual
Seed/Fruit type
Achene - a one-seeded, dry fruit
Seed identification features
Size
- length: 5.0–5.5 mm
- width: 3.0–3.5 mm
Shape
- in outline: obovate (upside-down and egg-shaped)
- in cross-section: angled
Surface texture
- slightly shiny
- roughened with ridges and oval pits
Colour
- bone coloured, becoming medium brown within pits on surface
Other structures
- pappus at top of achene
- may be persistent on processed seed
- made up of short, flattened bristles (up to 7.5 mm)
- usually pale, but may be brown coloured
- top peg is short, within a shallow depression surrounded by several projecting teeth
Similar species
Distaff thistle (Carthamus dentatus)
- not known if found in North America
- similar to woolly distaff thistle in size, obovate shape, pale colour and flattened pappus bristles
- achenes are not rough, and are duller than achenes of woolly distaff thistle
- achenes have brown band at top (woolly distaff thistle lacks this band)
Safflower (Carthamus tinctorius)
- found in BC, AB, and the western United States
- obovate shape, pale colour, glossy surface with brownish pits
- achenes are up to 2.0 mm longer than woolly distaff achenes
- pappus rarely persists
- pappus is made of thinner bristles than woolly distaff thistle
Photos
Similar species
