Waterblinks

Montia fontana L.

Family: - Portulacaceae.

Names:

Montia commemorates Giuseppe Monti (1682-1760) who was Professor of Botany at Bologna.

Waterblinks

Other names:

Montia

Summary:

A hairless, small, prostrate annual herb with paired leaves forming a loose untidy rosette like clump. Young plants are semi erect.

Description:

Cotyledons:

Two, 4-8 mm long, somewhat succulent with a petiole 4-8 mm long. Hairless. The seedling has a short hypocotyl and a short epicotyl though this may not develop until the seedling has grown beyond the two leaf stage. Tip rounded. Sides convex. Base tapered. Surface hairless

First leaves:

The early leaves have a blade 4 to 8 mm long with a petiole about the same length or rather longer, are hairless and are somewhat succulent in appearance.

Leaves:

Paired and at right angle to the pair below. Form a loose, untidy, rosette like clump.

Stipules - None.

Petiole - Short or absent. Hairless.

Blade - Spade shaped to elliptical, 5-15 mm long, with no midrib groove. Hairless.

Stem leaves - 15 mm long with a short or no petiole.

Stems:

Branch from the base, slender, up to 20-200 mm long, solid, circular in cross-section, soft, weak. Hairless and smooth. Roots at the lower nodes. Young stems are semi erect but become prostrate as they grow longer.

Flower head:

Small cymes, terminal or in upper leaf axils, occasionally single flowers. Flowers on short stalks

Flowers:

1-2mm diameter.

Ovary - Superior, 3 ovules. Style with 3 branches.

Sepals - 2, broad and flat topped to circular, persistent, 1 mm long.

Petals - White, tubular with 5 lobes, split open on one side. Slightly longer than the sepals.

Stamens - 3-5, attached at the top of the petal tube.

Anthers - Opening longitudinally on the inside (introrse).

Fruit:

Globular capsule with 3 seeds, opening in 3 valves.

Seeds:

Black, almost globular with concentric rows of tiny warts (tubercles).

Roots:

Taproot with fibrous roots from a lower stem nodes.

Key Characters:

5 lobed corolla. Tufted stems. White flowers with pedicels. Leaves and stems not succulent. Opposite leaves at right angles to the pair below. Annual. Anthers introrse.

Biology:

Life cycle:

Annual herb. Germination occurs in autumn and to a lesser extent in spring.

Physiology:

Reproduction:

By seed.

Flowering times:

September to December.

Seed Biology and Germination:

Vegetative Propagules:

Stems roots at nodes and may form daughter plants.

Hybrids:

Subspecies chondrosperma has 1 mm seeds with blunt or flat topped tubercles spread over the whole surface.

Subspecies amporitana has seeds less than 1 mm diameter and the tubercles around the keel are conical.

Allelopathy:

Population Dynamics and Dispersal:

Spread by seed.

Origin and History:

Australia.

Distribution:

ACT, NSW, SA, TAS, VIC.

Montia occurs in all parts of Tasmania, and is more common in the North than in the South.

Habitats:

Climate:

Temperate.

Soil:

Wetlands.

Plant Associations:

Wetland plants.

Significance:

Beneficial:

Ornamental.

Detrimental:

A weed of wet areas and crops but it is of little or no economic importance.

Toxicity:

Not recorded as toxic.

Legislation:

None.

Management and Control:

Thresholds:

Generally doesn't cause significant yield depressions.

Eradication strategies:

Herbicide resistance:

Biological Control:

Related plants:

White Purslane (M. australasica).

Plants of similar appearance:

Seedlings resemble Chickweed (Stellaria media) Montia is hairless, has no mid-rib groove on leaves and a broader petiole.

Mouse-eared Chickweed (Cerastium spp.) has hairy leaves

Scarlet Pimpernel (Anagallis arvensis) has a kite-shaped cotyledon with a short merging petiole and sessile leaves.

Australian Crassula, Dense Crassula, Spreading Crassula (Crassula spp.)

Chickweed (Stellaria media)

Four-leaved Allseed (Polycarpon tetraphyllum)

Mouse-eared Chickweeds (Cerastium spp.)

Pearlwort (Sagina apetala)

Pimpernel (Anagallis arvensis)

Pigweed (Portulaca spp.)

References:

Black, J.M. (1965). Flora of South Australia. (Government Printer, Adelaide, South Australia). P350-351. Diagram.

Burbidge, N.T. and Gray, M. (1970). Flora of the Australian Capital Territory. (Australian National University Press, Canberra). P161.

Hyde-Wyatt, B.H. and Morris, D.I. (1975). Tasmanian weed handbook. (Tasmanian Department of Agriculture, Hobart, Tasmania). P90-91. Diagram.

Lamp, C. and Collet, F. (1990). A Field Guide to Weeds in Australia. (Inkata Press, Melbourne).

Lazarides, M. and Hince, B. (1993). CSIRO handbook of economic plants of Australia. (CSIRO, Melbourne) #843.2.

Acknowledgments:

Collated by HerbiGuide. Phone 08 98444064 or www.herbiguide.com.au for more information.