Lactuca serriola
ASTERACEAEA
Prickly Lettuce, Compass Plant, Scarole
Annual or biennial plant, up to 2 m tall. A relative of cultivated lettuce. Originting in Europe, Asia & Africa.
Blue green leaves with saw toothed divided edges & a prominent mid vein up to 30cm long. Leaves grow along a spiny stem, progressively getting smaller towards the top. Similar to L.saligna but lacks spines on the lower stem but may have a few spines on the lower side of the leaves. Leaves on the stem follow a north south plane hence the name Compass Plant.
Pale yellow flowers, 15mm long, Oct to Feb with white seedheads that look like dandelions.
When cut it emits an irritating milky latex.
Colonizer of disturbed sites. Germinates in late Autumn & Winter. Leaves can be eaten when young though do taste bitter.
Minor crop weed in Australia. Can be found in gardens & alongside roads. Manually remove plants including the taproot with gloves or spray with appropriate herbicide before the flowering stems have started to elongate.