The broad-leaved marsh orchid grows mainly in nitrogen-poor marsh areas that consist of several plant communities. More rarely, it is found in fens. Its flowering period begins at lower elevations as early as the beginning of May and ends in higher elevations at the end of July. The lowest blossoms usually open even before the stem has reached its full height.
On average, Dactylorhiza majalis is 15 to 40 cm (6 to 15+1⁄2 in) tall, though specimens can grow up to 60 cm (2.0 ft).[7] Four to ten spotted leaves (either purple or burgundy in color) are distributed around the stem,[7][8] which is hollow.[citation needed] The leaves are ovate to lanceolate and 6 to 18 cm (2+1⁄2 to 7 in) long by 1.5 to 3.5 cm (1⁄2 to 1+1⁄2 in) wide, and get smaller and more lanceolate as they approach the inflorescence.[8] The bracts are about as long as the blossom and cover it before it blooms. The densely flowered inflorescence, which is approximately 5 to 15 cm (2 to 6 in) long,[8] is initially conical, but distinctly cylindrical when in full blossom. The seven to fifty blossoms are colored purplish red, rarely light pink or white. The lateral tepals of the external circle of the perianth stand obliquely or vertically upright. They are 7 to 12 mm (1⁄4 to 1⁄2 in) long and 2.5 to 5 mm (1⁄8 to 3⁄16 in) wide. The middle tepal is smaller and forms a "helmet" together with the two lateral tepals of the internal circle. These are 6 to 11 mm (1⁄4 to 7⁄16 in) long.[citation needed]The trilobate lip is 5 to 10 mm (3⁄16 to 3⁄8 in) long and 7 to 14 mm (1⁄4 to 9⁄16 in) wide. The shape and pattern of the lips are variable. In the lighter central area of the lip the markings are made up of lines, streaks, or dots. The spur is bent slightly downwards and is not quite as long as the ovary.[citation needed] The tuber has a palmate division and an irregular shape.[citation needed]
In 1828 Ludwig Reichenbach described the broad-leaved marsh orchid as Orchis majalis. The name became the basionym after Peter Francis Hunt and Victor Samuel Summerhayes transferred the species to the genus Dactylorhiza in 1965. Sometimes the name Dactylorhiza fistulosa is used, but since this description is not valid, the name cannot be used despite its earlier publication in 1794 as Orchis fistulosa.[citation needed]
This section needs to be updated. The reason given is: Kew World Checklist of Selected Plant Families now recognises 17 subspecies; search species name in ref. Please help update this article to reflect recent events or newly available information.(August 2023)
Dactylorhiza majalis is widespread across much of Europe and north-central Asia, from Spain and Ireland to Siberia and Kazakhstan.[10]
In Germany the broad-leaved marsh orchid is widespread but with several gaps. In many places, especially from western to northern Germany, it is extinct.
Although the broad-leaved marsh orchid is commonly found in some regions, it is nevertheless protected as an orchid.
As with many marsh plants, the numbers of this species have been dwindling for quite some time. The main causes are the entry of nitrogen via fertilizer, drying out of the habitat, and intensive conversion to pasture. The broad-leaved marsh orchid does not react so sensitively to changes in its habitat as for example the early marsh orchid, Dactylorhiza incarnata. It is usually the last of the native orchids to disappear. This tolerance makes it a still relatively common species.
^Ó. Sánchez Pedraja (2005). "Dactylorhiza Neck. ex Nevski". In C. Aedo; A. Herrero (eds.). Smilacaceae–Orchidaceae. Flora Iberica. Vol. 21. Real Jardín Botánico, CSIC, Madrid. pp. 94–111. ISBN8400083059.
^N. Griebl (2008). "Vorkommen und verbreitung der gattung Dactylorhiza in Österreich". Berichte aus den arbeitskreisen heimische orchideen. 25 (2): 80–118.