poorjoe
Family
RubiaceaeScientific Name
Diodia teres
Other Common Names:
common button weed
Synonyms (former Scientific Names):
Diodella teres
Habit
Prostrate, spreading, or slightly upright.
Leaves
Linear or elliptic, 3/4-1 1/2 inches long (2-4 cm), 0.08-0.24 inches wide (2-6 mm), opposite, without petioles, with a prominent midvein on both surfaces. Leaves are connected across the stem by a membrane that has several long (3-5 mm) hairs connected to it.
Identifying Characteristics
Erect or spreading annual with opposite, linear leaves and small white to pink or light purple flowers. Prostrate or slightly upright growth habit, small, white, 4-parted flowers, and membrane connecting each pair of opposite leaves helps to distinguish this plant from most other weeds. However, Virginia Buttonweed (Diodia virginiana) is very similar in growth habit and appearance but is a perennial with much wider leaves and stems that root at the nodes.
Flower Seed Head
Arise from a region between the stem and leaf (axillary), usually solitary, star-shaped, and consist of 4 small white sepals.
Seed Fruit
Small rounded fruit that is pubescent with 4 sepals protruding from the top surface.
Where Found
Found throughout the southeastern United States.
Growth Habit
Varies:
upright and nonwoody,
prostrate and nonwoody
Thorns or Spines
not present
Approximate Flower Diameter
pencil
Dominant Flower Color
Varies:
white,
purple,
pink
Flower Symmetry
radial symmetery
Leaf Hairs
no hairs
Leaf Shape
lance
Leaf Arrangement
opposite
Leaf Margin
entire
Leaf Structure
simple
Leaf Stalk
none
Stem Hairs
has hairs
Stem Cross Section
round or oval
Milky Sap
not present
Root Structure
fibrous
Life Cycle
summer annual
Ochrea
Varies:
present,
not present
Plant Type
Herb