Cota tinctoria

Morphological description

Perennial or sometimes biennial plant, with a height generally ranging between 20 and 50 centimeters, Golden Chamomile is characterized by a woody rhizome, often with a suffruticose appearance, from which ascending herbaceous stems develop, simple and covered with a grayish tomentosity. The stem has a cobwebby surface, giving the plant a slightly woolly appearance.

The leaves are bipinnatisect, about 2-3 cm long, with linear-lanceolate lobes and serrated margins. The leaf teeth end in a small cartilaginous mucro, which gives precision and detail to the leaf edge. The leaves are pubescent, contributing to the overall woolly appearance of the plant.

The flowers appear in solitary capitula, with a diameter between 2 and 2.5 cm, supported by a thickened peduncle. The involucre of the capitulum is composed of imbricated scales, with a pale yellow or yellowish woolliness, the inner scales being sharper. The receptacle, convex or conical, is equipped with lanceolate, membranous-scarious or cartilaginous chaffs, firmly attached. The peripheral flowers are ligulate, bright yellow in color, generally female and, in some cases, may be absent; their length is shorter than the central part of the capitulum. The central flowers are hermaphroditic, tubular and five-toothed, with yellow or whitish coloration and have a cylindrical ovary.

The fruit is an achene with a rhombic section, noticeably compressed, with prominent veins but without wings. The achene can be glabrous or crowned by a short membranous structure, entire or ear-shaped.

The root system consists of a superficial, woody and often suffruticose rhizome, which allows the plant to survive and regenerate over the years.

Habitat and distribution

Golden Chamomile is mainly widespread in temperate Europe, with a range extending from France to Ukraine, including the Pontic area around the Black Sea. In Italy it is present throughout the territory with two subspecies, although the actual distribution of these is not always well documented.

It prefers habitats characterized by dry meadows and roadside edges, with a particular preference for calcareous substrates. It grows from sea level up to about 1500 meters altitude, demonstrating a high adaptability to different climatic and environmental conditions. Its hardiness allows it to thrive both in warm areas and in those subject to cold.

Flowering period

Flowering generally occurs from May to September, thus extending over most of the summer season. No significant geographical variations in the flowering period have been reported; however, local climatic conditions may influence its exact duration.

Ecology and pollination

The plant presents a floral structure typical of Asteraceae, with capitula formed by peripheral ligulate flowers and central tubular flowers. Pollination is entomogamous, mainly mediated by pollinating insects attracted by the bright yellow color of the flowers and their scent.

The presence of central hermaphroditic flowers ensures fertilization, while the ligulate female flowers may facilitate the attraction of pollinating insects. Seed dispersal occurs through the achenes, which are wingless but equipped with membranous structures that may favor limited dispersal by wind or through contact with animals and soil.

Curiosities and traditional uses

Golden Chamomile is a medicinal species known since ancient times for its dyeing and medicinal properties. The specific name "tinctoria" refers precisely to its use in fabric dyeing, due to the presence of yellow pigments belonging to the flavonoid group. Although it has been cultivated mainly in North America and Great Britain for this purpose, in continental Europe it has been less used due to the presence of other more valued dye plants, such as Reseda luteola and Serratula tinctoria.

In popular medicine, the dried capitula were used similarly to those of Chamaemelum nobile and Matricaria chamomilla: to prepare infusions, macerates and balsamic, diaphoretic and stimulating potions. The pleasant and subtle aroma of the flowers favored their use as a calming agent against migraines and to aid digestion. For external use, preparations based on this plant were applied to redness and skin or eye inflammations.

The essential oil extracted from the capitula is used in cosmetics for the preparation of creams and hair lightening solutions, as well as exerting an effective sedative action when applied locally. The hardiness of the plant and its large yellow flowers also make it appreciated in ornamental gardening, where it is cultivated both in open ground and in pots, with good resistance to variable climatic conditions.

Etymology

The genus name, Cota, derives from the Greek “kòta”, meaning “cup”, probably referring to the shape of the capitula or the receptacle. The specific name "tinctoria" indicates the traditional use of the plant as a source of dyes, particularly to obtain yellow pigments used in fabric dyeing.

The Italian common name "Golden Chamomile" directly recalls this affinity with dyeing and distinguishes its appearance from other chamomile species better known for their medicinal or aromatic properties.

Sources

• Acta Plantarum - Flora delle regioni italiane (actaplantarum.org)
• Acta Plantarum - Flora delle regioni italiane (scheda di Daniela Longo)