Posted by
valleylynn (Oregon City, OR - Zone 8b) on Dec 15, 2011 1:34 PM concerning plant:
An abundant seed-producing summer annual with hairy leaves and stems, reaching 2 feet in height. Primarily a weed of vegetable crops, however it may occur in any cultivated situation. Found throughout the eastern and midwestern United States, and also on the west coast.
Identifying Characteristics: Hairy stems and leaves, and 3-toothed ray flowers. The densely hairy nature of this weed helps to distinguish this weed from smallflower galinsoga (Galinsoga parviflora), which is very similar but much less hairy than hairy galinsoga.
Seedlings: Cotyledons club-shaped with slightly indented tip. The stem below the cotyledon (hypocotyl) is very short, green, becoming maroon with age. Young leaves opposite, triangular with slightly toothed margins, and covered with hairs.
Leaves: Opposite, oval to triangular, coarsely-toothed, petiolated, and densely covered with hairs on the upper surface. Lower leaf surfaces have hairs that primarily occur on the veins.
Flowers: Many flowers are produced from terminal stems or from the areas where petioles meet the stem (leaf axils). Flowers are less than 1 cm wide and consist of 4 to 5 white (or less often pink), 3-toothed ray flowers (outer flowers) and many yellow disk flowers (inner flowers).