Prostrate knotweed is a summer annual that germinates early in the season and exhibits prostrate growth. Due to its early germination it has the ability to rapidly drain soil resources, in many cases to the detriment of the competing crop. The growth of prostrate knotweed can also be a good identifier for compacted soil, where this weed can grow well under a diversity of conditions.
The cotyledon of prostrate knotweed is linear, narrow in shape and is easily mistaken for grass.
The leaves of a mature plant are alternate and have extremely short petioles (connection between leaf and main stem). Leaves range from 2-6 cm and are a bluish-green colour. Stems vary in length from 10-60 cm and are light-green in colour. The prostrate knotweed has thin, wiry stems with distinct swelling at the nodes, which is a key characteristic in identification of this broadleaf weed. As well, the silver-papery ochrea emphasizes the nodes. The flowers are extremely small and very inconspicuous. They grow in cluster ranging from 1-5, which are white in colour, though may exhibit a pink tint to them.
Optimal growth conditions
Prostrate knotweed grows well on compacted soils, especially roadsides and walking paths.