Arenaria patula Michx.

Arenaria patula plant

Family - Caryophyllaceae

Stems - Multiple from base, from fibrous roots, dichotomously branching, glabrous to glandular pubescence, thin (-1mm in diameter), to +/-20cm tall, erect, herbaceous.

Leaves - Opposite, linear, +/-1.5cm long, 1-1.5mm broad, entire, glabrous, sessile.

Arenaria patula leaves

Inflorescence - Terminal loose cymes. Each division of cyme with a small pair of bracts subtending. Bracts lanceolate. Pedicels to 1.3cm long, filiform, glabrous or with sparse glandular pubescence.

Flowers - Flowers to +/-5mm broad. Petals 5, white, glabrous, 6mm long, 1.4mm broad, with a shallow notch at apex, spreading at tips. Stamens 10. Filaments 2mm long, filiform, glabrous, white. Anthers yellow, .4mm long. Ovary ovoid, glabrous, 1.1mm long, .8mm in diameter. Styles 3, 1mm long, glabrous, white. Sepals 5, erect, distinct, with 5-nerved, green, glabrous or with some glandular hairs, lanceolate, with scarious margins, to 4mm long, 1mm broad. Fruit a small capsule. Seeds many, black, -.5mm in diameter.

Arenaria patula flowerFlower close-up.

Arenaria patula calyxCalyx close-up.

Arenaria patula fruitFruit close-up.

Flowering - April - June.

Habitat - Glades and rocky prairies.

Origin - Native to U.S.

Other info. - This little plant is found in the lower 1/2 of Missouri. When not in flower the plant is easy to overlook because it is so small and has very thin stems. While in flower the small white corollas are easy to spot in the plant's glade habitat. This species is very short-lived but the dead stems can be found throughout the year.

Photographs taken in Lebanon, TN., 5-16-03, and at Dave Rock Conservation Area, St. Clair County, MO., 6-7-03.