|
Key identifying traits
Several yellow flower heads per stem arranged in an umbrella like
cluster
Flower petals are strap-shaped with notched tips
Leaves are mostly basal, somewhat hairy
Stems generally leafless and 14 to 36 inches tall with hairs
Plants contain milky juice and develop above ground runners, like
strawberry plants
Biology and ecology
- A perennial spread by windborne seeds, below ground rhizomes and
above ground stolons
- Can form near monocultures with few other plants apparent on the
dominated sites
- Tolerates shade but thrives in open meadows
- Has fibrous root system and can invade lawns
- Flowers in late June and July
Control
Prevention Learn to identify
plants; know your property; beware of fill dirt, hay and seed from outside
your area, clean vehicles and equipment that have been in hawkweed areas
Biological None available, research ongoing
Cultural Good vegetative cover helps avoid initial infestation
but can invade and dominate healthy sites
Mechanical Will not withstand regular tillage but cutting and
pulling are ineffective unless done with frequency and diligence to
eliminate re-growth
Chemical Several effective at label rates; exercise care
working around desirable shrubs and trees to avoid damage;
refer to the
PNW Weed Management Handbook for specific chemical recommendations |
