Back to the Prairie Platanthera

We really lucked out this past June when Casey and I took a trip to the northwest of Missouri in search of the two state-endangered prairie-fringed orchids. We were not sure if we would find Platanthera leucophaea (eastern prairie-fringed orchid) at all and chances were iffy to find both species flowering simultaneously. During some years, there may be gaps in the phenology of flowering of these two species in the state, which would require at least a couple of these long trips. As mentioned above, we not only found both species in our search but found them both at near-peak bloom.

First up is Platanthera praeclara (western prairie-fringed orchid) that we found in a reliable spot in Harrison County.

The state-endangered and federally-threatened Platanthera praeclara was photographed with a backdrop of tallgrass prairie in Harrison County, MO
Naturally pollinated by nocturnal sphinx moths, some state programs are now hand-pollinating prairie-fringed orchids in efforts to increase populations and reintroduce the plants to new areas.

We were thrilled to find a population of approximately 40 Platanthera leucophaea (eastern prairie-fringed orchid) plants at a Grundy County location.

A pair of Platanthera leucophaea stand tall in a wet prairie in Grundy Co, MO.
The long nectar spurs require an insect with a long proboscis to act as pollinator of Platanthera leucophaea.
A pair of grasshopper nymphs feeding on Platanthera leucophaea. This was the only plant we observed with heavy arthropod feeding pressure like this.

Missouri Orchids – Liparis loeselii – Fen Twayblade

Liparis loeselii (fen twayblade, Loesel’s twayblade) is ranked as imperiled in the state of Missouri. We found these in a marly fen in Butler County, MO in bloom during late May, 2021. Within this fen, these orchids grow on the edges between small tussocks and the marl/muck, out of the way of larger competitive plants.

A raceme of Liparis loeselii at peak bloom.
A Liparis loeselii plant in bloom with two clasping leaves surrounding the flowering stem. Note the remains of the stem and seed capsules of previous year.
It may come as no surprise, due to the plain and diminutive flowers of Liparis loeselii, but this plant is considered autogamous (self-fertilizing).

-OZB