The field gentian, Gentianella campestris is a strictly biennial herb that primarily occurs in semi-natural grasslands due to its dependence on consistent management (ie. grazing or mowing, Lennartsson 2000). It is one of six species of Gentianella in Sweden and occurs from Småland to Västerbotten and Jämtland (Naturhistoriska riksmuseet 1998, ArtDatabanken 2007).

The field gentian germinates in spring and forms a small rosette the first summer. It overwinters as a bud and a taproot and flowers in early July or mid August the following year, depending on phenologic variety (Lennartsson 2015, Wettenstein 1895 cited in Lennartsson et al. 1998). The flowers are bluish-purple or white, have four petals and produce around 500-1100 seeds (Lennartsson, 2015). The plant stem is about 5-20 cm high (ArtDatabanken 2007). The only known pollinator is bumblebees and the species has no vegetative propagation but it is highly selfing (Lennartsson and Oostermeijer 2001).

A study by Milberg (1994) showed that the species has a very short-lived seed bank and is therefore highly dependent on continuous seed production. Other studies have shown that grazing or mowing can have a positive impact on the reproduction of G. campestris as it induces overcompensation in the seed production (Lennartsson et al. 1997, 1998). However, grazing throughout the growing season may significantly increase the risk of extinction, compared to traditional management with mowing in July and autumnal grazing (Lennartsson & Oostermeijer 2001).

The species is strongly linked to nutrient poor, species-rich seminatural grasslands and can therefore serve as an indicator species (Lennartsson & Oostermeijer 2001, ArtDatabanken 2007). The Swedish red-list highlights loss of management as one of the main threats for the field gentian population (ArtDatabanken 2007). Loss of management can quickly affect the population as accumulating plant litter shades the seedlings and increases the mortality. This might be the factor that limits recruitment the most (Lennartsson & Oostermeijer 2001). Another effect of management loss is increased vegetation height, which in the summertime can hamper the rosette development (Lennartsson & Oostermeijer 2001).

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