This is an orchid endemic to France and which has its headquarters in the southern Vercors area of Drome
indeed its name means "from Drome". It has a few other stations in adjoining Provinces such as the Ardeche, Bouches-du-Rhone and possibly Isere.
Its a very local orchid but can be frequent in its favoured areas, and these areas always seem to be a dry
location in full sun - rocky hillsides, garrigue, abandoned olive groves and light woodland. Its preferred habitat is always at altitude though usually in the Alpine foothills between 250 and 1000 meters rather than in the high mountains.
O. drumana is easily recognized as a member of the O. bertolonii group and at up to 40cms is certainly one of its more sturdy members. It's also one of the most distinctive species in the group and although somewhat variable, not readily confused with any other of its cousins (not least by virtue of its isolated range). Its distribution is thought to marginally overlap with the similar O. saratoi and it may possibly hybridise, though there seems to be little formal record of this having been noted.
As already mentioned, O. drumana can be a fairly variable orchid with notable differences in both lip shape and speculum colour (see the variation between photo's 4 and 10). It can be a tall plant with up to a
dozen flowers and is most commonly found growing in small, loose colonies.
These llustrations are all from the southern Vercors, predominently in the area between the small towns of Combovin and Beafort-sur- Gervanne. They date from the last week of May.
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