Plants of South Eastern New South Wales
Rumex hypogaeus
Common name
Spiny Emex, Three-cornered Jacks, Doublegee
Family
Polygonaceae
Where found
Weed of crops, disturbed sites, rocky areas, and along streams. Sydney area and north. Blue Mountains. Occasionally elsewhere.
Notes
Introduced annual herb, prostrate or sprawling, sometimes to 0.40 m tall. The 'petals' of female flowers tipped with very sharp rigid spines. Seed cases with 3 rigid, spreading spines. Plants somewhat fleshy. Stems hairless. Leaves alternating along the stems, 2-9 cm long, 15-70 mm wide, margins more or less finely scalloped. Male and female flowers on the same plant. Flowers small (less than 3 mm in diameter), with 6 spreading 'petals', united at least at the base. Male 'petals' about 2 mm long. Flowers in clusters at the bases of the leaves. Flowers most of year, mainly Apr.–Nov.
Was Emex australis.
General Biosecurity Duty all NSW. Noxious weed Vic.
PlantNET description: https://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Rumex~hypogaeus (accessed 18 March 2021)
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