Thlaspi

Thlaspi is a genus of flowering plants in the mustard family, Brassicaceae. It is characterized by its small, often flattened, or winged siliques, which are the fruit characteristic of the family. The genus is found in temperate regions of the Northern Hemisphere, with a significant concentration in Europe and Asia. Species within Thlaspi are typically herbaceous annuals, biennials, or short-lived perennials. They often have basal rosettes of leaves, with stem leaves that are usually simple and entire. The flowers are typically small and white or pale pink, with four petals, and are borne in racemes.

Many species formerly classified under Thlaspi have been reclassified into other genera, such as Noccaea and Hornungia, due to advances in phylogenetic research. This has led to some taxonomic debate and variation in the definition of Thlaspi. Common characteristics used for identification include the shape and size of the silique and the presence or absence of a distinct wing on the fruit. Some species, like Thlaspi arvense (field pennycress), are widespread and can be considered weeds in agricultural settings due to their prolific seed production and ability to colonize disturbed ground. Other species are more localized and may be found in specific habitats like alpine meadows or rocky slopes. The genus plays a role in its ecosystems, providing food and habitat for various invertebrates and serving as a component of plant communities.