Lesser jack: pest

Page last updated: Wednesday, 8 April 2020 - 6:09pm

Please note: This content may be out of date and is currently under review.

Lesser jack (Emex spinosa) is an uncommon weed in Western Australia (WA). This article describes the nature of the plant with links to control methods.

Form: herbaceous — annual

Status: present in WA

Appearance

Native to the Mediterranean and North Africa. E. spinosa is very similar to doublegee (E. australis) but with fruits and spines half the size. It has a more upright habit than E. australis.

Leaves: The first leaves have longer stalks (petioles) than E. australis, that is they are longer than the leaf blade whereas in E. australis the petioles are shorter than the leaf blade.

Fruits: Smaller four to five millimetres long (compared to 7 to 11 millimetres for E. australis), with shorter spines that are more bent back. Eight to ten pits on each face of the fruit.

Declared pest category

The Western Australian Organism List (WAOL) contains information on the area(s) in which this pest is declared and the control and keeping categories to which it has been assigned in Western Australia (WA). Use the links on this page to reach lesser jack in WAOL.

Search > detect > record

Record: this pest by using the MyWeedWatcher smartphone and tablet application or online recording tool.

Control method

When using any agricultural chemicals please ensure that you always follow instructions on the label and any permit. Users of agricultural chemical products must always strictly comply with the directions on the label and the conditions of any permit.

Only registered products can be used for weed and pest control.

Control methods for this plant can be found through the APVMA website, use "spiny emex" as the pest name.

Contact information

Pest and Disease Information Service (PaDIS)
+61 (0)8 9368 3080