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

Cardamine flexuosa (Wavy bittercress)

Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Rosids
Order: Brassicales
Family: Brassicaceae
Genus: Cardamine
Species: C. flexuosa
Binomial name: Cardamine flexuosa
Common names: Wavy bittercress, Woodland bittercress

Cardamine flexuosa is a herbaceous, highly variable, annual or biannual depending on environmental conditions. It is in the cabbage family (Cruciferae) and is originally from Europe. It is found scattered across New Zealand in a variety of environments over a wide range of light and disturbance conditions. It favours moist shady places. It flowers vigorously and forms dense root mats that can exclude other species.
It grows to a height of no more than 50 cm with few short, erect, wavy stems. The stem arises from a basal rosette of leaves that have about 5 rounded stalked leaflets on each side and a larger one at the end. 
The white flowers are very small, no more than 3 – 4 mm across and they have six stamens. The flowers are hermaphrodites (having both male and female organs) so the plant is self-pollinated. The seed pods are about 12 - 25 mm long and when ripe explode dispersing hundreds of small seeds many metres. The seeds are sticky when wet and can be easily spread on clothing or animals. The seeds can remain viable in the seed bank for up to seven years.

Cardamine flexuosa can be distinguished it from Cardamine hirsute by:
1. C. flexuosa has a wavy stem, C. hirsute has an ascending to erect stem.
2. C. flexuosa has a deeply grooved stem c2mm wide with short hairs to 0.5mm.
C. hirsute has a slight ridge stem c1mm wide and is hairless or with much shorter hairs 0.1mm.
3. C. flexuosa flowers have six stamens. C. hirsute has 4-5 stamens.
4. C. flexuosa fruits generally not overtopping the flowers.

C. flexuosa six stamen flower

Juvenile plants.

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