Dactylorhiza maculata - Heath Spotted Orchid

Scientific Name: Dactylorhiza maculata. 'Dactylo' is from the Greek for finger, and 'rhiza' is Greek for root, reflecting the palmate form of the tubercules. 'Maculata' is from the Latin for 'spotted', referring to the brown spots on the leaves.

English Name: Heath Spotted Orchid. The name reflects the plant's requirement for the low pH soils of heaths and the like. The spots the name references are on the leaves.

French Name: Orchis des bruyères (='heath orchid'). Also Orchis à feuilles tachetées ('=spotted leaved orchid'), Orchis maculé (='spotted orchid'), Orchis tacheté (='spotted orchid').

5 Key Characters:
  • Leaves with more or less circular brown spots
  • Lower lip very shallowly lobed
  • Mid-lobe much narrower and shorter than side-lobes of lower lip
  • Lower lip markings streaks and loops, not dots
  • On acid soils, not calcareous
Lookalikes: Every other Dactylorhiza sp, but especially D. fuchsii.

The Dactylorhiza spp have a reputation for cross-breeding readily, making identification to species level difficult, but this seems to be a misconception and they are in fact more commonly just extremely variable within each species.

There are several subspecies of D. maculata, difficult to separate and with distributions which are poorly understood. The subspecies around Preuilly, D. m. subsp. ericetorum, has paler petals than the species, often virtually white rather than pink, and with a particularly wide lower lip (wider than it is long). The lateral sepals (side petals) tend to point forwards rather than out to the sides.

Habitat: Strong preference in the Brenne for swampy heaths and grasslands, and near Preuilly occurs by ditches along roads through the Parc de Boussay and the wider logging tracks in the Fôret de Preuilly. In general the habitat includes both dry and wet heaths; bogs, marshes and swamps; peaty roadsides and woodland edges or clearings; fallow grassland, pasture and poor acid grasslands, sand, clay. Rarely occurs on calcareous soil or in areas of high cultivation. Likes full sun or semi-shade.

Flowering Period: May-June-July.

Status: Locally common (ie occurs in several very specific places, where it is abundant). Threatened by the draining of swamps, and in decline. Can be seen within 5km of Preuilly-sur-Claise, the Touraine Loire Valley, Sologne and in the Brenne. Most often spotted on track or road sides.

Recorded by Loire Valley Nature:

3 June 2008 Parc de Boussay (roadside)

Top right: roadside ditch and forest edge – typical habitat for this species.
Bottom left: typical spotted leaves. Bottom centre left: leaf rosette in April on the roadside in the Parc de Boussay.

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