Scientific Name: Diodia teres

Common Name: poorjoe

Other Common Names: common button weed

Synonyms: 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 (<a href='../../weedimg/653'>Diodia virginiana</a>) 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.

  • Life cycle: summer annual

  • Milky sap: Not Present

  • Plant type: Herb

  • Thorns: Not Present

  • Plant family: Rubiaceae

  • Leaf arrangement: opposite

  • Leaf shape: lance

  • Leaf margin: entire

  • Ochrea: Not Present; Present

  • Stem hairs: has hairs

  • Flower color: purple; pink; white

  • Growth habit: upright and nonwoody; prostrate and nonwoody

  • Stem: round or oval

  • Leaf structure: simple

  • Leaf hairs: no hairs

  • Root structure: fibrous

  • Flower symmetry: radial symetery

  • Flower diameter: pencil

  • Leaf stalk: none