common groundsel
Family
AsteraceaeScientific Name
Senecio vulgarisOther Common Names:
old-man-in-the-spring
Habit
This erect winter annual flowers from April through October. Depending on climate, it may also act as a summer annual, or a biennial. 3 to 4 generations may develop during one growing season.
Leaves
The alternately arranged leaves have deeply lobed margins, and are irregularly tooted. Leaves may be sparsely hairy, although most are hairless. The upper leaves are directly attached to the stem while the lower leaves have a short petiole.
Identifying Characteristics
This plant contains pyrrolizidine alkaloids which are harmful to horses, cattle, swine, and even humans, causing liver damage and possibly, death. Smaller herbivores such as rabbits and goats are resistant to the plant's effects.
Flower Seed Head
The yellow flowers occur in clusters in the ends of stems. Each disk-shaped flower can grow up to 1 cm in diameter.
Seed Fruit
Seeds develop in reddish brown to gray-brown achenes. The achenes have soft white hairs, and when in clusters, form puff balls like that of the Dandelion, easing dispersion by wind.
Where Found
This weed can be found in moist nutrient rich areas, such as lawns and flowerbeds.
Growth Habit
upright and nonwoody
Thorns or Spines
not present
Approximate Flower Diameter
pencil
Dominant Flower Color
yellow
Flower Symmetry
radial symmetery
Leaf Hairs
Varies:
has hairs,
no hairs
Leaf Shape
lance
Leaf Arrangement
alternate
Leaf Margin
serrated
Leaf Structure
simple
Leaf Stalk
none
Stem Hairs
Varies:
has hairs,
no hairs
Stem Cross Section
round or oval
Milky Sap
not present
Root Structure
Varies:
fibrous,
taproot
Life Cycle
winter annual
Ochrea
not present
Plant Type
Herb