narrowleaf hawksbeard
Family
AsteraceaeScientific Name
Crepis tectorumHabit
Seedlings have ovate 10-12 mm long by 2-3 mm wide hairless ovate cotyledons. Reaching heights of 1 m the narrow-leaved hawk's-beard is a prolific seed producer. It has a branched taproot that reaches deep into the soil. Narrow-leaved hawk's-beard has hairless leafy stems. All parts of this plant when broken exude a milky latex sap.
Leaves
Stalked lance-shaped basal leaves are 10 to 15 cm long and 4 cm wide, with numerous backward-pointing teeth to deeply lobed segments. Stem leaves are stalkless, less than 1 cm wide, and they clasp the stem. Frequently the margins of the stem leaves roll under toward the midrib.
Identifying Characteristics
Milky juice, Yellow flowers 10-15 mm across, and leaves with backward pointing lobes.
Flower Seed Head
Flower heads in groups of 5 are found n the branches. Heads usually measure 10-15 mm across with 30 to 70 yellow ray florets. The basal rosette of leaves disappears before the first flowers appear.
Seed Fruit
Each floret produces an achene bearing a dark purplish brown spindle-shaped 3-4 mm long seed. Seed coats bear 10 prominent ribs that are rough to the touch. The pappus has numerous white hairs that aid in seed dispersal. Narrow-leaved hawk's-beard is capable of producing as many as 49,000 seeds with no dormant period required for germination.
Where Found
Found throughout Canada and the United States in forage crops, roadsides, pastures and waste areas. Can be a serious weed in fall sown crops where the basal rosette is not controlled by spring cultivation.
Growth Habit
Varies:
upright and nonwoody,
prostrate and nonwoody
Thorns or Spines
not present
Approximate Flower Diameter
pencil
Dominant Flower Color
yellow
Flower Symmetry
radial symmetery
Leaf Hairs
has hairs
Leaf Shape
lance
Leaf Arrangement
rosette
Leaf Margin
Varies:
lobed,
serrated
Leaf Structure
simple
Leaf Stalk
none
Stem Hairs
no hairs
Stem Cross Section
round or oval
Milky Sap
not present
Root Structure
taproot
Life Cycle
biennial
Ochrea
not present
Plant Type
Herb