T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network

Lactuca virosa (Bitter lettuce)

Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Asterids
Order: Asterales
Family: Asteraceae
Tribe: Cichorieae
Genus: Lactuca
Species: L. virosa
Binomial name: Lactuca virosa
Common names: bitter lettuce, wild lettuce, Opium lettuce, Poisonous lettuce, Tall lettuce, Great lettuce

Lactuca virosa is a plant related to common lettuce (L. sativa). It is native to central and southern Europe and North Africa. It is found throughout the New Zealand’s North Island and in the north of the South Island. Its habitat is waste areas, roadsides, railways and industrial sites.

Lactuca virosa is generally an annual, although an occasional it is biennial, it can grow to 200 cm. It has stout, green, red or purple blotched stems. The leaves are purple flushed. The stem leaves are scanty, alternate, clasping the stem with two small lobes.  The leaves tend to be held flat.
The flower heads are numerous and shortly-stalked, The bright yellow flowers are 12-18 mm in diameter. They appear during December-February. The fruit is purple-black, flattened achenes (seeds), with pappus which is a long silvery tuft of hairs. The whole plant will bleed milky latex from any laceration.


The underside of a leaf.

Thanks to Wikipedia for text and information: https://creativecommons.org/licenses/by-sa/3.0/