Mollugo verticillata L.

Carpetweed

© SRTurner

Family - Molluginaceae

Habit - Annual forb from branched taproot.

Stems - Prostrate and mat-forming, to 40 cm, branched, glabrous, with slightly swollen nodes.

	Stem and node.
© SRTurner

Leaves - In whorls of 3-8, simple. Blades 8-40 mm long, broadly to narrowly oblanceolate to nearly linear, rounded or pointed at the tip, narrowed gradually at the base, sessile or with a short, winged petiole 1-4 mm long, entire, glabrous, with a single prominent midvein.

	Stem and leaves.
© SRTurner

	Leaf whorl.
© DETenaglia

	Leaf whorl.
© DETenaglia

	Leaf adaxial.
© SRTurner

	Leaf abaxial.
© SRTurner

Inflorescence - Axillary clusters of 1-5 flowers. Flower stalks slender, glabrous, 5-15 mm long, drooping in fruit.

	Inflorescences.
© SRTurner

	Inflorescences.
© SRTurner

Flowers - Sepals 2.0-2.5 mm long, elliptic or narrowly oblong, white or pale green, externally with 3 green vertical lines (united at the apex) and white margins, glabrous. Petals absent. Stamens 3 or 4, white, glabrous, 1.4 mm long. Anthers yellow, to 0.3 mm long. Ovary of 3 united carpels, globose, superior, glabrous, green. Placentation axile. Styles to 0.4 mm long. Stigmas on very short, curved styles.

	Flowers.
© SRTurner

	Flower.
© DETenaglia

Fruits - Capsules 2.5-3.0 mm long, ovoid to ellipsoid. Seeds 0.6 mm broad, without a caruncle or linear appendage, but with a minute peglike protuberance at the attachment point, the seed coat with several arching ridges along the sides and back, shiny, dark reddish brown.

	Flower and fruit.
© SRTurner

	Fruits.
© SRTurner

	Dehiscent fruit and seeds.
© SRTurner

Flowering - May - November.

Habitat - Streambanks, often in sandy soils, fields, gardens, roadsides, railroads, open disturbed areas.

Origin - Native to Central and South America; naturalized nearly worldwide.

Lookalikes - Sherardia arvensis; broadly, species of Galium.

Other info. - This mat-forming weed can be found throughout Missouri, and also across much of the continental U.S. It is uncommon or absent in western Plains and mountain states. It is easily recognized by its flat, wiry aspect, whorled leaves, and tiny white flowers. The plants grow and mature quickly, sometimes progressing from seed germination to flowering within the space of a few days.

Photographs taken at the Honey Creek Conservation Area, MO., 6-14-03 (DETenaglia); also near Labadie, Franklin County, MO, 7-27-2022 (SRTurner).