Tuesday, September 30, 2014

Platanthera aquilonis

 Platanthera aquilonis, the Northern Green Bog Orchis, is another of the hard-to-identify green Platantheras.  Indeed, because the Platantheras seem to interbreed quite freely it is sometimes impossible to identify them with certainly.  The distinguishing characteristics of this species are a yellowish lip, a spur that is shorter than the lip and curved well forward, and anther sacs that are low in the flower and form a kind of triangular shape.  The plant can be quite small to 60 cm tall and has numerous flowers, as many as fifty, more or less crowded on the flower spike.  The leaves are near the ground and up to 20 cm.  We do not see this species as frequently as some of the other green Platantheras and seldom in Washington, but have found it in a number of different locations in the Canadian Rockies in British Columbia and Alberta.

July 8
(Canadian Rockies)

July 10
(Canadian Rockies)


  1. It seems, that they are quite complicated to tell apart. As you know I misidentified at least one. Our two species are quite easy to identify.
    However, we have the same problem with Dactylorhiza (a lot of species, that hybridize easily and look rather similar) and especially with Epipactis, where even the experts sometimes have a hard time identifying.
    Ophrys might be easy in Germany (with 4 species + 1 subspecies), even though they hybridize easy enough and especially O. apifera has lots of variations, but in the mediterranean it is way more complicated.

    Anyways: the post (and the others on the green Platantheras) will be very useful, next time I come across one. You show great pictures where one can see the attributes to go by.

    1. Trust you are well, Martin, and thanks for the comments. Your description of the species in your area makes me all the more eager to see them.

      As to the green Platantheras, the one you misidentified is probably the easiest to identify once one has seen it, since it grows only in serpentine areas and is usually not found with the others. It was a long time, however, before I was comfortable with my identifications and there are still plantsthat confound even the experts. One of them said to me when I asked him to identify a plant, "it's a green Platanthera."