What is this weed with tiny yellow flowers found in eastern Australia?

Question

It grows very fast in summer. Hundreds of little round seeds seem to grow on stems where the leaves join to the main stem. Wind or manual removal causes them to fall off everywhere.

Older stems seem to turn brown/reddish, with newer growth stems being green.

It's located in eastern Australia, in a cool temperate climate. It has taken off massively after recent rains followed by steady 20°C temperatures.

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I can't tell, are the stems square? – Grady Player Feb 04 '15 at 13:34 — Grady Player, Feb 04 '15 at 13:34

score 1 · Answer 1 · edited Jul 29 '15 at 08:38

1

Difficult for me to say as I'm in France, but it sounds to be a Chenopodiaceae (family)... You may look on the side of Polygonum, chenopodium... It is maybe Chenopodium pumilio

Hope it leads you on a good "path" ;)

edited Jul 29 '15 at 08:38

Patrick B.

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answered Jul 28 '15 at 08:21

RPO

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score 0 · Answer 2 · answered Jul 28 '15 at 08:39

It looks like it some species of bacopa. Bacopa is known to grow wild in that region and has similar characteristics.

A close up of the blooms would prove helpful in determining the genus, species. I found this picture of wild Bacopa but cannot determine if the the flowers are a match or not.

Please post when you find out!

What is this weed with tiny yellow flowers found in eastern Australia?

2 Answers2