Phytolacca americana L.

Global description

Phytolacca americana is an erect plant, woody at the base, branched, 1 to 3 m high. The stem is erect, branched, and usually red. The leaves are simple, alternate, oval, and glabrous. Many small white flowers occur in terminal or lateral clusters, and are firstly erect then falling gradually as the fruit ripens. The fruits are fleshy globular berries, black, wrinkled at maturity.
 
Cotyledons
 
The cotyledons are sub-triangular, 15 to 20 mm long and 8 to 10 mm wide, with the base attenuated in petiole of 8 to 12 mm long, the upper surface light green in colour and tinted with purple, particularly on the venations, on the lower surface, glabrous.
 
First leaves
 
The leaves are simple, alternate, petiole 12 to 15 mm long. The lamina is elliptic lanceolate, 20 to 30 mm long and 12 to 16 mm wide, light green on the upper side and somewhat reddish at the underside, glabrous.
 
General habit
 
Plant is woody at its base, with an erect growth habit extensively branched, measuring 2 to 3 meters in height and diameter.
 
Underground system
 
The plant has a deep taproot.
 
Stem
 
The stem is robust, cylindrical, more or less ridged, solid, often tinged with red and more or less dotted with small white spots.
 
Leaf
 
Leaves are simple, alternate, stalked, not stipulated. The petiole is 6 to 30 mm long. The blade is elliptical oval to narrowly oval, 10 to 25 cm long and 3 to 10 cm wide. The base ending is wedged, often asymmetrical and sometimes slightly decurrent along the petiole. The apex is acute to acuminate or rarely rounded and scalloped. The margin is whole and both sides are glabrous. The conspicuous venation is arched, the ends of the ribs join together before reaching the edge of the leaf blade.
 
Inflorescence
 
The inflorescence is a multiflora contracted cluster, terminal or axillary, erect at flowering and pending at maturity, 5 to 20 cm long and 15 mm wide, at flowering and 35 m during fruiting. A cluster consist of 10 to 50 flowers, white or tinted pink, briefly stalked (4 to 5 mm) at the base with a small linear bract 3 mm long. Axis of the cluster and stalks are often tinged with crimson.
 
 
Flower
 
The flower consists of a perianth, 5 to 6 mm in diameter at flowering, with 5 white roses petal-like pieces. About 10 stamens in a single series.
 
Fruit
 
The fruit is a fleshy, sub spherical, flattened berry, 10 to 12 mm in diameter, pericarp is very thin green black and purple. It wrinkles longitudinally while drying, highlighting 8 to 12 seeds arranged in orange quarters.
 
Seed
 
Seed is kidney-shaped, ovoid, laterally compressed, shiny black, 3 mm long and wide.

Origin

Phytolacca americana is native to the USA and Mexico.

Worldwide distribution

This species has been introduced in countries around the Mediterranean (Europe and Maghreb), in Africa (Zaire, South Africa), in the Indian Ocean (Madagascar, Mauritius and Reunion), in South-East Asia, Australia, New Caledonia and New Zealand.

https://www.gbif.org/fr/species/3084015