Rorippa palustris
Ordinary yellow-cress ( Rorippa palustris)
The Ordinary yellow-cress ( Rorippa palustris) is a flowering plant in the family of cruciferous plants ( Brassicaceae). It comes in Central Europe usually widespread.
- 2.1 General distribution
- 2.2 Spreading in Germany
- 2.3 for location
Description
Vegetative characteristics
The Ordinary cress growing as annuals, rarely, a few years perennial herbaceous plant, reaching heights of growth of about 20 to 60 cm. The upright, angular stem is branched often sparrig at least in the upper part and is bald or short hair in the lower part.
All leaves are auriculate at the base and mostly bare. The lower leaves are stalked, lyre-shaped fiederteilig and have four to eight pairs of oblong, lobed serrated lateral portions with a large, egg-shaped end portion. The top sheets usually have two to six pairs of side portions, which are generally somewhat smaller than those of the lower leaves. The stem leaves cover the stems mostly clear.
Generative features
The Ordinary cress predominantly flowers from June to September. The hermaphrodite, radial symmetry flowers are cruciform. The four green sepals have a length of about 2 mm. The four petals are either the same length or a little shorter and pale yellow.
The seated on an approximately 4 to 8 mm long, almost horizontal stem pod is oblong, often slightly curved, about 5-9 mm long and 2 to 2.5 mm thick. The products in two rows of seeds are brown to yellowish- brown, egg-shaped with a length of 0.5 to 0.9 mm and a diameter of 0.4 to 0.6 mm or nearly spherical
The set of chromosomes is 2n = 32
Occurrence
Popularization
Rorippa palustris is very common nowadays almost cosmopolitan. In Austria it comes to moderately frequently distracted while they can be found widely distributed in Switzerland.
Distribution in Germany
The Ordinary cress is widespread in Germany and most commonly found.
Habitat requirements
The Ordinary cress growing in Two Dental Ufersaumgesellschaften. It prefers moist, nutrient-rich, nitrogen-containing humic mud floors. It grows on the banks of watercourses, ditches and waste places wetter.