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Plant
longevity
annual or biennial
perennial
armature
unarmed
armed
Leaves
arrangement/phyllotaxy
basal
alternate
blade division
all simple
deeply lobed or divided
some or all fully compound
leaf attachment
sessile or nearly so
leaf stalk (petiole) clearly present
leaf (leaflet) margin
entire
toothed
Inflorescence
type
solitary
cymose
Composite Traits
head type
discoid (disk only)
radiate (rays and disks)
Denver Botanic Gardens Chatfield Thistles (ID)
Melissa Islam
Species Count: 7
Asteraceae
Carduus acanthoides
Carduus nutans
Cirsium arvense
Cirsium ochrocentrum
Cirsium undulatum
Cirsium vulgare
Onopordum acanthium