By Skip Via
skip@westvalleynaturalists.org

Although most people think of orchids as tropical plants, Montana is home to 31 species of orchids, almost all of which are found in the western part of the state. In the West Valley area of the Flathead Valley, the orchid you are most likely to encounter is the beautiful Calypso orchid. “Most likely” in this case does not mean common–they’re still a rare treat to encounter on a hike.

Calypso orchids (Calypso bulbosa) are also known as Venus slippers or fairy slippers. They are early bloomers, emerging in our area in May or June. There is a reason for this–they need bumblebees as pollinators, but they do not produce any nectar. They rely on deceiving the bees into thinking they offer nectar with their bright colors, sweet scent, and yellow hair-like structures that look like they might be anthers covered in pollen. Because bees learn quickly not to visit Calypso orchids in search of a quick meal, the orchids must attract the earliest emerging bees–typically male workers.

Calypso orchids occur all around the circumpolar north in Scandinavia, Russia, and Canada. They favor the shade of deep conifer forests and like soil that is light and rich in organic matter. They grow from a bulb and have single leaf that overwinters and produces blooms in the spring. A single plant may live for five years, although most don’t.

In our area, they can be seen along some of the more out of the way paths in the Pig Farm State Trust lands in the early spring. Although a single plant can produce thousands of seeds, they are on the decline due to a variety of factors–habitat loss, invasive species, etc.–and due to the fact that they require a specific a specific fungus living on its roots underground for most of their nutrition. This relationship (mycorrhizal) is symbiotic–the fungus receives nutrition from the orchid’s photosynthesis and the orchid gets help with water and nutrient uptake from the soil. If the thousands of seeds don’t find exactly the right soil conditions, they won’t germinate and grow.

So if you’re fortunate enough to see one in the spring, take pictures and let it be.

For more on local orchids, see Spotted Coralroot Orchid.