The shoes of the fisherman’s wife

Crossposted to The Clade

Long johns in the morning, shorts in the afternoon. It’s trout season, pale bellies peeking from the creel.

These slippers have evolved to fit — or rather, not to fit — a very specific “foot”: a large queen bumblebee, such as Bombus vagans or Bombus borealis. As one paper puts it:

Despite the flower’s bright color, conspicuous “nectar guides,” and sweet smell, the pink lady’s slipper produces no nectar. Once a bumble bee has entered a flower through the labellum slit, the infolded margins ensure that the sole exit point lies upward, at the labellum base. To exit, the bee first brushes against the stigma and then an anther.

The lady’s slipper orchid abuses the trust not only of trapped bees, but sometimes of its fungal symbionts, as well:

The tiny seed of orchids contains little or no food reserves for the embryo, unlike most seeds. In order for the seed to germinate and develop, it must become associated with certain fungi found in most soils. The fungus nourishes the developing seedling until finally, after two or three years, the plant has leaves large enough to sustain itself by photosynthesis. At this point, the seemingly ungrateful orchid will sometimes cast off its fungal partner.

Pink lady’s slippers (Cypripedium acaule) flourish in small openings in heath-understory oak-pine woodlands and other open forests with acidic soils. Like the oaks, pines and blueberries with which they associate, they flourish after ground fires, reaching their peak of blooming some ten to fifteen years after a fire. However, they are not uncommon in our maturing second-growth woods, either; the thinning of the canopy following the initial wave of gypsy moth caterpillar defoliation in 1980 and 81 probably helped them out a bit. And our habit of maintaining a network of old woods roads, which date back to the early 19th century, seems to provide favorable habitats, as well. We have to step carefully this time of year.

The flowers pictured here, though, grow right inside the woods above my house, in what has become the thickest stand of lady’s slippers on the mountain: close to forty plants, producing at least fifteen blooms each year. They can be hard to spot among the lowbush blueberries, which are also flowering now. According to the paper from Ecology magazine that I quoted above, the blueberries and huckleberries may represent other species stepped on by the lady’s slipper orchid on its route to reproductive success:

In this study, Cypripedium plants near ericaceous shrubs, particularly blueberry, appeared to be far more successful than Cypripedium plants in other areas. […] As bumble bees visit the nectar-producing blueberry flowers, they may be tempted to explore the large pink lady’s slipper flower. When bumble bees are abundant among blueberry bushes, these exploratory visits may be frequent, leading to a high pollination success rate.

Botanists struggle for objectivity when discussing orchids, some species of which actually mimic female insects, inducing the males to try and mate with them. Terms like “deceitful” or “deceptive” seem to have given way now to the less moralizing “nonrewarding.” Except that, of course, for a human observer, the contemplation of these flowers is very rewarding indeed. Perhaps this is what Charles Mingus had in mind with the title of one of his greatest compositions. The shoes of the fisherman’s wife are some jive-ass slippers.