NSP - Amaranthus retroflexus




Family: Amaranthaceae

Common names: Redroot pigweed, Bledo rojo

Ecol. & Biol: Annual. Root: a tap root. Stem: erect, upto 20-80 cm tall, upper parts branched, lower stem often red or red striped, red colour continues down to roots.

Leaves: dull green, spotted, 3-15 cm long, 15-17 mm wide, on thin and long petioles, with prominent veins, broad and lance shaped.

Inflorescence: 20 cm long, flowers - small, greenish or usually crimson, borne on erect terminal clusters, fruit - a capsule, seeds - shiny black or dark brown, about 1 mm long with sharp ridges. Propagation by seed.

Flowering time: July - September. 

Distribution: Occurs throu-hout Mongolia in frequently cultivated fields. Grows well under good fertility conditions and vegetables. 

Closely related weeds: A. caudatus L. with more pointed leaves and longer inflorescence.

Control measures: Very competitive but not difficult to control with either cultivation or herbicides applied post-emergence in cereals and pre-emergence in vegetables.

An annual pubescent plant with fleshy, long, erect stem, of pink colour, up to 1-1.5 m tall, leaves alternate sparsely haired. Inflorescence of many flowers forming a terminal panicle of 5-15 cm long. Each flower produces a single tiny, dark brown seed.

The plant grows well in moist soils and under warm temperatures. Seeds of the plant overwinters either deep or close to the soil surface.

The plant reproduces by seeds. A single plant produces thousand of seeds.

It is a common weed in cultivated areas, orchards and waste places.

Among the plants of genus Amaranthus, A. retroflexus is the most widespread in temperate areas of North America, Europe and Asia.


Countries: Iran, Jordan, Mongolia,Syria


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