L., the name Linnaeus gave the species Rhinanthus crista-galli var. fallax (Wimm. & Grab.) Druce Rhinanthus rigidus Chabert Rhinanthus stenophyllus (Schur) Schinz & Thell Rhinanthus crista-galli var. fallax (Wimm. & Grab.) Druce Rhinanthus kyrollae Chabert Rhinanthus borealis subsp. kyrollae (Chabert) Pennell Distribution and ecology Rhinanthus minor is found in Europe, western Russia, western Siberia, northern USA and throughout Canada. The preferred habitat of Rhinanthus minor is dry fields or meadows, where its flowering period is in the summer between May and September, but it can thrive with semi-natural species-rich water-meadows. It can tolerate a wide range of soil types but does not grow where the soil has a pH less than 5.0. Yellow rattle flowers are pollinated by bumblebees during the summer months; the plant is also capable of self-fertilization. Yellow rattle is an annual wildflower. It is hemiparasitic, in that it can gain its nutrients by penetrating the roots of neighbouring green plants with its own roots, but is a facultative parasite, in that it acts opportunistically when in contact with a root. The hemiparasitic nature of yellow rattle can result in stunted, unbranched individual specimens. The plant can associate with many different host species, notably Poaceae (grasses) and Fabaceae (legumes). In Ireland and Scotland, yellow rattle is often associated with Machair habitat, which consists of coastal grassland. The seeds are spread effectively by traditional hay-making practices. Farmers seek to remove it since it affects yields by weakening grass; it is an indicator of poor grassland. Effects on plant community structure Yellow rattle can change the structure of plant communities through its parasitism. Vulnerability to attack varies across host taxa, with forbs developing lignified barriers to obstruct the parasite. Research, including that at the UK's Centre for Ecology and Hydrology, has shown that encouraging it to grow in hay meadows greatly increases biodiversity, by restricting grass growth and thereby allowing other species to thrive. As of 2021 a majority of studies had found positive or neutral effects of the introduction of Rhinanthus spp. on grassland species richness and diversity, with most finding a negative effect on grasses. Conservation status Rhinanthus minor is found in low-lying fields with poor quality soil. It is currently not under threat; as such it is rated as of Least Concern (LC). Being an annual, it is not found in regularly mown or grazed grassland where the seeds are not provided with an opportunity to