Polygonum aviculare - prostrate knotweed

	DISSEMINATION

Kingdom	Plantae
Sub Kingdom	Tracheobionta ( vascular plant)
Superdivision	Spermatophyta (seed plant)
Division	Magnoliophyta (flowering plant)
Class	Magnoliopsida (dicotyledon)
Order	Polygonales
Family	Polygonaceae
Genus	*Polygonum*
Species	*aviculare*
Classification	L.
Common Name	prostrate knotweed

Geographic Range	unknown native area; it is widespread all over the world.
Physical Characteristics	it has a hard and flexible stem; it is an annual plant which reproduces only by seed. The stems are branched and they spread from the root in every direction forming a carpet with an up to 1.5 meter diameter. It is seldom erect, even if on moist and rich soils the ends can rise up from the ground up to 20 centimeters. The green-bluish leaves are alternate, elongated and lanceolate. They may be from 0.5 to 4 centimeters long; they have a very short petiole surrounded by a thin sheath. The leaves can be very dense on the stem or far from each other. The flowers are white or pink, clustered at the leaf axils in the upper part of the plant. It flowers from March to October.
Notes	it tolerates well stamping and drought.
Habitat	it grows well on compacted soils.

Sources
References	Government of Manitoba - Minister of Agriculture and Food The University of Arizona Press
Web References	http://www.gov.mb.ca/agriculture/crops/weeds/index.html http://www.uapress.arizona.edu/
Source of the photo	http://www.css.orst.edu/weeds/id.html