tropical chickweed

Drymaria cordata subsp. cordata
Tropical chickweed
Tropical chickweed
Tropical chickweed
Tropical chickweed sprout
Tropical chickweed to scale
Tropical chickweed
Tropical chickweed
Tropical chickweed
Tropical chickweed plant detail
Tropical chickweed
Herb
Opposite
Simple
White
Green

A short-lived herbaceous plant with weak stems growing up to 20 cm tallits slender stems are green and hairless or sparsely covered with sticky hairsits paired leaves (5-35 mm long and 5-30 mm wide) are kidney-shaped or broadly egg-shaped in outlineits small white flowers are loosely clustered towards the tips of the branches. its small capsules (1.5-2.5 mm long) are egg-shaped (i.e. ovoid) and contain a few reddish-brown seeds.

Common names 
Also known as: drymaria, heartleaf drymary, whitesnow,
Family 
Caryophyllaceae
Deciduous 
No
Flowering time 
Year round
Native/Exotic 
Exotic
Origin 
This species is widespread throughout the tropical regions of the world (i.e. pan-tropical) and its exact native distribution is obscure. However, it is thought to have originated in tropical America.
Notifiable 
No
Council declaration 
SIL – Special Investigation List
Known distribution 

Widely naturalised and relatively common in the coastal districts of south-eastern Queensland (i.e. in the Moreton and Wide Bay districts). Also naturalised in north-eastern New South Wales and the coastal districts of central and northern Queensland.

Habitat 

A weed of pastures, crops, gardens, footpaths, roadsides, waste areas, disturbed sites, riparian vegetation, open woodlands and forest margins. It prefers moist and shady sites.

Habit 

A short-lived (i.e. annual) herbaceous plant with weak upright (i.e. erect) or sprawling (i.e. decumbent or ascending) stems growing up to 20 cm tall. It sometimes develops roots at its lower joints (i.e. nodes).

Impact and control methods 
Stem and leaves 

The slender stems are green and hairless (i.e. glabrous) or sparsely covered with sticky (i.e. glandular) hairs. The paired leaves are borne on stalks (i.e. petioles) 2-15 mm long and are kidney-shaped (i.e. reniform) or broadly egg-shaped in outline (i.e. ovate). These leaves (5-35 mm long and 5-30 mm wide) have entire margins and rounded or slightly pointed tips (i.e. obtuse or sub-acute apices). They are hairless (i.e. glabrous) or sparsely covered with sticky (i.e. glandular pubescent).

Flowers and fruits 

The small flowers are loosely clustered towards the tips of the branches (i.e. in terminal or axillary cymes) and are borne on stalks (i.e. pedicels) 2-15 mm long. These flowers have five narrow green sepals (3-5 mm long) that are covered with sticky (i.e. glandular) hairs. They also have five white petals (2-3 mm long), two or three stamens, and an ovary topped with three styles. The five petals are usually deeply two-lobed, and may be easily mistaken for ten petals at first glance. Flowering occurs throughout most of the year. The small capsules (1.5-2.5 mm long) are egg-shaped (i.e. ovoid). They contain a few reddish-brown seeds (1-1.5 mm across) that are shaped like a snail shell (i.e. cochleate).

Reproduction and dispersal 

This species reproduces only by seed. These seeds are probably spread by wind, water, vehicles, in mud and in contaminated agricultural produce.

Similar species 

Tropical chickweed (Drymaria cordata subsp. cordata) can be confused with chickweed (Stellaria media), lesser chickweed (Stellaria pallida) and mouse-ear chickweed (Cerastium glomeratum). These species can be distinguished from each other by the following differences: tropical chickweed (Drymaria cordata subsp. cordata) has hairless stems and relatively small hairless leaves (6-12 mm long). Its flowers have five white petals that are deeply lobed, and may appear to be ten petals at first glance chickweed (Stellaria media) has a line of hairs along one side of its stems and relatively large hairless leaves (5-25 mm long). Its flowers have five white petals that are deeply lobed, and may appear to be ten petals at first glance lesser chickweed (Stellaria pallida) has a line of hairs along one side of its stems and relatively small hairless leaves (less than 7 mm long). Its flowers do not have any petals.mouse-ear chickweed (Cerastium glomeratum) has very hairy stems and relatively large hairy leaves (5-32 mm long). Its flowers have five white petals that are deeply lobed, and may appear to be ten petals at first glance.