Mollugo verticillata L.

Carpetweed

Mollugo_verticillata_plant.jpg
STATS

Introduced
CC = *
CW = 0
MOC = 68

© SRTurner

Family - Molluginaceae

Habit - Annual forb from branched taproot.

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

Mollugo_verticillata_stem.jpg 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.

Mollugo_verticillata_stem2.jpg Stem and leaves.

© SRTurner

Mollugo_verticillata_node.jpg Leaf whorl.

© DETenaglia

Mollugo_verticillata_leaves.jpg Leaf whorl.

© DETenaglia

Mollugo_verticillata_leaf1.jpg Leaf adaxial.

© SRTurner

Mollugo_verticillata_leaf2.jpg Leaf abaxial.

© SRTurner

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

Mollugo_verticillata_inflorescence1.jpg Inflorescences.

© SRTurner

Mollugo_verticillata_inflorescence2.jpg 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.

Mollugo_verticillata_flowers.jpg Flowers.

© SRTurner

Mollugo_verticillata_flower.jpg 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.

Mollugo_verticillata_fruit1.jpg Flower and fruit.

© SRTurner

Mollugo_verticillata_fruit2.jpg Fruits.

© SRTurner

Mollugo_verticillata_fruit3.jpg 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).