dogfennel
Family
AsteraceaeScientific Name
Eupatorium capillifolium
Other Common Names:
dog-fennel thoroughwort
Habit
20 in to 6 1/2 ft in height, with 1 to several stems from a thick woody base. Many small flower heads are created from the upper stem branches. Leaves are pinnately dissected into fine, linear segments. Stems are erect, starting from the woody base, much-branched in the upper flowering portion, hairy, or sometimes smooth below, reddish purple at the base. It has fibrous roots and a woody stem at the ground level that sometimes resembles a taproot. Upright flowering stems persevere through the winter and often into spring. In warmer climates, young plants may die back to the crown and resprout in the spring. Dogfennel characteristically shows itself in nurseries, orchards, crops with decreased tillage, and landscapes. It also grows in abandoned fields and roadsides.
Leaves
Seedling: Cotyledons are egg-shaped, petiolated, and hairless. Young leaves are opposite; the first and sometimes the second pair of leaves have 1-3 coarse teeth, but successive leaves are dissected. Blades are hairy. Mature Plant: Majority of the leaves are alternate; some lower leaves may be opposite. Leaves are once or twice pinnately dissected into fine linear segments.
Identifying Characteristics
When crushed, leaves and particularly flowers give off a strong foul odor.
Flower Seed Head
Flowers are generated in September and October. Flower heads are small and abundant, in much-branched panicles on the upper 1/3-1/4 of the upright stem. Individual heads are small, 2-3 mm long, with 3-6 greenish white disk flowers on each head.
Seed Fruit
Reproduces by seed. The seed is enfolded within the fruit (achene), which is smooth, gray to black, angled in cross section, widest at the apex and 1-1.6 mm long The pappus consists of whitish bristles.
Where Found
Found along the coastal plain from Massachusetts south, all through the Southeast to Texas; generally found anywhere from New Jersey southward
Growth Habit
Varies:
upright and nonwoody,
woody bush or tree
Thorns or Spines
not present
Approximate Flower Diameter
pencil
Dominant Flower Color
Varies:
white,
green
Flower Symmetry
not symmetrical
Leaf Hairs
no hairs
Leaf Shape
needle
Leaf Arrangement
alternate
Leaf Margin
Varies:
lobed,
serrated
Leaf Structure
pinnate
Leaf Stalk
Varies:
none,
shorter than leaf
Stem Hairs
Varies:
has hairs,
no hairs
Stem Cross Section
round or oval
Milky Sap
not present
Root Structure
Varies:
fibrous,
taproot
Life Cycle
perennial
Ochrea
not present
Plant Type
Herb