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Key identifying traits
Single, 1-3" wide, yellow flower heads on erect, unbranched,
leafy stems 2-5' tall
Broadly lance-shaped leaves have sharp pointed tips, shallowly toothed
edges and rough surfaces
Leaves change from simple stalks to winged stalks to no stalk as they
become smaller up the stem
Bracts surrounding the flower head are wider than long, mostly brown
with lighter margins appearing in 8-12 layered rows
Seeds are ¼" long with pale to brown plumes
Biology and ecology
- A perennial that reproduces by seed with up to 200 seeds per head
- Sold commercially as an ornamental under the names "Lemon fluff" or
"Globe centaury"
- Found only as an escaped ornamental to date but competes vigorously
in heavy grass stands in areas with loam soils and 20 inches of
precipitation
- Remains green in August & palatable to livestock
- Generally has only one or two stems 2-3' tall with 1½"
heads when found competing with grass but as an ornamental may be 5' tall with 3" heads on each of multiple stems
Control
Prevention – Learn to identify
plants; know your property; beware of aggressive ornamentals
Biological – None known
Cultural – Competing vegetation helps limit spread
Mechanical – Repeated tillage, digging or cutting are all
effective if properly timed to prevent seeds
Chemical – Several can be effective if applied early in growth
cycle;
refer to the
PNW Weed Management Handbook for specific chemical recommendations |
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