Backyard Natural Wonders – 2022 Highlights

I love watching nature documentaries like those narrated by David Attenborough, but even more than that I love watching the natural wonders that surround me every day.

This post features a few of my favorite sightings from 2022.

A pair of Eastern Bluebirds eating berries from American Holly (Ilex opaca)

Eastern Bluebirds visit us more often in fall and winter than in spring or summer. In addition to holly berries, they love our heated birdbath, an important source of fresh water in the cold winter months.

Eastern Bluebird, Male
Eastern Bluebird, Female

I always love it when an animal reminds me of the value of plants or other habitat that humans sometimes question. The male Northern Flicker (Yellow-shafted here in New Jersey) in the photo below did just that while enjoying Poison Ivy (Toxicodendron radicans) drupes, a berry-like fruit in the woods across from our house.

Northern flicker eating Poison Ivy (Toxicodendron radicans) drupes, a berry-like fruit in the woods across from our house

Bottlebrush Buckeye (Aesculus parviflora) is a constant source of entertainment when it blooms in mid-summer, attracting butterflies, Ruby-throated Hummingbirds, Hummingbird Moths, and many different bees and other insects to visit for nectar.

Eastern Tiger Swallowtail nectaring from Bottlebrush Buckeye (Aesculus parviflora)
Dark form female Eastern Tiger Swallowtail drinking nectar from Bottlebrush Buckeye (Aesculus parviflora). She’s disguised as a Pipevine Swallowtail in an attempt to look unpalatable to potential predators such as birds.
Hummingbird Clearwing Moth nectaring from Bottlebrush Buckeye (Aesculus parviflora). Notice the ant also visiting the flowers, foraging for nectar or other insects to eat.

I understood why large long-tongued bees like Eastern Carpenter Bees visited the long, narrow, tubular flowers, but I puzzled over why so many tiny bees would buzz around the plant, since their anatomy isn’t a good fit for the flower size and shape.

Eastern Carpenter Bee drinking nectar from Bottlebrush Buckeye (Aesculus parviflora) flowers
Sweat Bee harvesting pollen from Bottlebrush Buckeye (Aesculus parviflora) flower

As I watched more closely, I saw tiny sweat bees (Halictid species) landing on the anthers (the flower part from which pollen is dispensed) to harvest pollen, both for themselves and to bring to their nests to feed their larvae. Bees and some flies may visit flowers for pollen, an important food source for them. Both their athleticism and creative thinking was impressive.

An acrobatic Sweat Bee harvesting pollen to bring to her nest to feed her larvae. Notice the pollen she has packed on her hind legs perfectly matches the color of the pollen she is harvesting.

A Sweat Bee taking an easier approach to harvesting the pollen she needs.

From a different access point, the sweat bees managed to drink nectar from the flowers, but without their bodies touching the flowers’ reproductive parts, so they weren’t likely to be doing the plant any favors in exchange for the nourishment provided.

Sweat Bee attempting to access this flower’s nectar. The bee’s body isn’t touching the flower’s reproductive parts, so it’s unlikely pollination will occur as a result of this transaction.

The starburst arrangement of abundant stamens (male reproductive parts) in the flowers of Shrubby St. Johnswort (Hypericum prolificum) are such a successful attraction to potential pollinators that this plant doesn’t waste any energy producing nectar.

Bumble Bee harvesting pollen from the profusion of anthers on a Shrubby St. Johnswort (Hypericum prolificum) flower.
Many bees are attracted to Shrubby St. Johnswort (Hypericum prolificum) for the potential of harvesting ample pollen from its flowers.

In late July I found a Striped Hairstreak in our habitat, my first time seeing this species. This butterfly was not only new for me, but it’s rare where I live in New Jersey.  What was it doing in my garden?  Striped Hairstreaks are typically found at forest edges where there are nectar sources, and with nearby access to its caterpillar foods – oaks, walnuts and hickories.  We have nectar sources, and there are suitable caterpillar food trees nearby, so check and check.  

My first ever sighting of a Striped Hairstreak, a butterfly that is rare where I live in New Jersey.

Catbirds arrived in spring and stayed through mid-fall. I saw them just about every day, usually in pairs, but sometimes in groups of four or more. Early one afternoon in August I witnessed a young Catbird being tutored on the proper way to take a bath.

Young Catbird delicately swirling the water in our birdbath, with adult supervision.
The adult Catbird coach provides guidance, saying, ‘Really get your whole body into it. Flap your wings! Don’t be afraid.’
The young Catbird gives it another shot.
“That was refreshing!”
The young Catbird, “How was that?” The adult supervisor, “Now you’ve got it!”

As Flowering Dogwood (Cornus florida), Winterberry Holly (Ilex verticillata) and Blackhaw Viburnum (Viburnum prunifolium) fruit ripened, the Catbirds were joined by migrating birds who passed through, using our habitat as a rest stop.

Catbird in fall, surrounded by ripening Flowering Dogwood (Cornus florida) fruit.
A migrating Swainson’s Thrush happily ate Winterberry Holly (Ilex verticillata) fruit.
Although surrounded by fruit, this female Purple Finch preferred to eat a caterpillar when visiting our habitat.

My favorite event was a visit from a Sleepy Orange in late September. 

Sleepy Orange (winter color form) on Virginia Creeper (Parthenocissus quinquefolia) in my New Jersey garden in late September

I love this butterfly for its pioneering ways. It’s mainly a tropical butterfly, but works to extend its range northward, positioning itself for continued survival in these days of climate change.  Instead of the southward migration strategy for winter survival employed by many insect and bird species, some Sleepy Oranges fly north in late summer and fall. I imagine them getting together, looking for volunteers to fly north, saying, “See if you can survive the winter in a place where you can find nectar for yourself and a partner, and food for the kids (caterpillars).  If you succeed, great!  We’ve extended our range. If not, no big deal, we adults will all be dead by late spring anyway.”  I’m not sure that’s what really goes on, but I like to pretend it is.

Sleepy Orange (winter color form) on Blue Wood Aster (Symphyotrichum cordifolium) in my New Jersey garden in late September

At one time the Sleepy Orange was thought to be unable to survive the winter any farther north than North Carolina. But they are now seen fairly often in central New Jersey and eastern Pennsylvania, and may have established year-round colonies.  I first encountered a Sleepy Orange in 2006 at nearby Bowman’s Hill Wildflower Preserve, but this was my first sighting of the species in my own habitat.  Very exciting!  This year I had nectar to offer this thirsty butterfly, but to extend its range it needs the food its   caterpillars require, Wild Senna (Senna Hebecarpa, S. marylandica) or Partridge Pea (Chamaecrista fasciculata). I didn’t have the necessary caterpillar food to offer this year, but we’ll have some Wild Senna by next summer.

Sleepy Orange drinking nectar from Blue Wood Aster (Symphyotrichum cordifolium)
Sleepy Orange drinking nectar from Thin-leaved Sunflower (Helianthus decapetalus)

No matter what time of year, there is always something interesting to see right outside our doors. I have my desk facing the windows so I can be easily distracted by wildlife. Even on a winter day I may see Box Elder Bugs, Chickadees, Titmice, Carolina Wrens, White-breasted Nuthatches, Juncos, White-throated Sparrows, Red-bellied Woodpeckers, Downy Woodpeckers, Robins, Bluejays, Pileated Woodpeckers, Yellow-bellied Sapsuckers, Cedar Waxwings, or Brown Creepers. Some visit for fruit, but many are gleaning insects from the branches, bark and leaves of trees and shrubs, and from the fallen leaves on the ground.

Red-tailed, Sharp-shinned and Coopers Hawks sometimes stop by. On rare occasions, a Bald Eagle does a fly-over.

Want to see more wildlife?  Make your own backyard an inviting habitat. Just provide the food birds, butterflies, bees and other animals need in the form of plants native to your region, and do less: leave fallen leaves in your planting beds, leave spent perennials standing, don’t use pesticides, herbicides or fertilizers, reduce your lawn if you can.  

You don’t need to have a large property to host and see wildlife. We live in an end unit in a townhouse development with a homeowners’ association (HOA), adjacent to commonly owned natural areas that were preserved when the development was built more than 30 years ago. (Note that we leave the leaves, standing spent perennials, and don’t use pesticides.) Even a planter or a window box can bring wildlife within view.

Why travel thousands of miles away from home to see wildlife, when you can make exciting discoveries in your own backyard?  

Chickadee foraging on Blue Wood Aster (Symphyotrichum cordifolium), looking for seeds or insects

Related Posts

Sleepy Orange Butterflies are Back

A Wildlife, Family, and Pet-friendly Lawn

‘Will Work for Food’ – Extra-floral Nectaries

Bountiful Blue Wood Aster

Shrubby St. Johnswort

Where Do Winterberries Come From?

Invasion of the Cedar Waxwings

Holiday Gift Ideas for Your Wild Neighbors

A Lovely Native Chickweed

As I rounded a bend while walking a trail on a cool day earlier this spring, I spotted a colony of wildflowers blooming a few inches above ground level. 

A colony of spring wildflowers
A colony of mystery spring wildflowers

My first thought was that it must be Spring Beauty (Claytonia virginica), whose blossoms were beginning to carpet the forest floor, but I quickly realized it must be something else. These flowers were a purer white, showing no hint of the pink nectar guides and anthers that add a bit of blush to Spring Beauty’s floral display. 

Spring Beauty (Claytonia virginica). Note the pink stripes (nectar guides) on the petals, and the pink anthers.
Spring Beauty (Claytonia virginica). Note the long, narrow leaves, the pink stripes (nectar guides) on the petals, and the pink anthers.

Clearly this was a different species. I needed to take a closer look.

Notice the upright stems with short opposite leaves, and more leaves at the base of the plant.
Notice the upright stems with short opposite leaves, and more leaves at the base of the plant.

While these plants were similar in height to Spring Beauty, they were more erect, less sprawling. Their leaves were short, opposite each other along the stem, with additional leaves at the base of the plant.

The flowers had five distinctly lobed petals, and instead of pink striping, these had soft gray nectar guides beckoning pollinators to visit.  

Notice the deeply notched white petals with soft gray striping.
Notice the deeply notched white petals with soft gray striping, characteristics of Field Chickweed (Cerastium arvense ssp. strictum).

A little investigation yielded the identification as Field Chickweed (Cerastium arvense ssp. strictum), a plant native throughout much of Canada and the United States (except Kansas, Oklahoma, Texas, Louisiana, Virginia, North Carolina, South Carolina, Alabama, and Florida).  In spite of Field Chickweed’s wide range, this was my first encounter with it.  This perennial chickweed is often found on cliffs, rocky slopes, ridges, ledges or beaches.  Fittingly, I met this small beauty on a rocky western-facing slope near the Delaware River in the Sourland Mountains in New Jersey.

Field Chickweed (Cerastium arvense ssp. strictum) with flower visitor
Field Chickweed (Cerastium arvense ssp. strictum) with flower visitor

The primary pollinators documented for this species are a number of bees, including small carpenter bees, cuckoo bees, mason bees, sweat bees, and mining bees. Conveniently located nearby were nest entrances for some ground nesting bees who may have been frequent diners at the Field Chickweed flowers.

Entrance to ground-nesting bee nest in the path to the right of some Field Chickweed (Cerastium arvense ssp. strictum).
Entrance to ground-nesting bee nest in the path to the right of some Field Chickweed (Cerastium arvense ssp. strictum).

In contrast to the documentation I found for this plant, the pollinators I encountered were all flower flies (also known as hover flies or Syrphid flies).

Field Chickweed (Cerastium arvense ssp. strictum) with flower fly actively drinking nectar
Field Chickweed (Cerastium arvense ssp. strictum) with flower fly actively drinking nectar
Field Chickweed (Cerastium arvense ssp. strictum) with visiting flower fly
Field Chickweed (Cerastium arvense ssp. strictum) with visiting flower fly
Field Chickweed (Cerastium arvense ssp. strictum) with Eastern Calligrapher (Toxomerus geminatus)
Field Chickweed (Cerastium arvense ssp. strictum) with Eastern Calligrapher (Toxomerus geminatus), a species of flower fly

Flower flies are named for their frequent visits to flowers to drink nectar and eat pollen, and for their ability to hover in the air. Flies are important pollinators, especially in spring and fall when the weather is cool, because they are able to fly at lower temperatures than many bees.   

The seeds of this and other chickweeds are eaten by many birds and small mammals, including mice.

Deer Mouse (Peromyscus maniculatus). Mice will eat chickweed seeds.
Deer Mouse (Peromyscus maniculatus). Mice will eat chickweed seeds.

Those small mammals may become food for other animals, like this Red Fox.

Red Fox, "Yum! Mice are delicious!"
Red Fox, “Yum! Mice are delicious!”

Field Chickweed is a lovely little native plant quietly doing its job in the ecosystem. I’m happy to have made its acquaintance.

Field Chickweed (Cerastium arvense ssp. strictum)
Field Chickweed (Cerastium arvense ssp. strictum)

Related Posts:

A Tale of Two Spring Beauties

Resources

Eaton, Eric R.; Kauffman, Ken.  Kaufman Field Guide to Insects of North America.  2007.

Skevington, Jeffrey H.; Locke, Michelle M.; Young, Andrew D.; Moran, Kevin; Crins, William J.; Marshall, Stephen A.  Field guide to the Flower Flies of Northeastern North America. 2019.

Flora of North America

Go Botany

Illinois Wildflowers

Lady Bird Johnson Wildflower Center Plant Database

USDA NRCS Plant Database

USDA U.S. Forest Service Plant of the Week

Invasion of the Cedar Waxwings!

Swift movement outside the window caught my eye, as a bird landed in a nearby tree branch. Was that a Cedar Waxwing?

Cedar Waxwing
Cedar Waxwing

Another bird came in for a landing.

Two Cedar Waxwings
Two Cedar Waxwings

Then another.

Three Cedar Waxwings!
Three Cedar Waxwings!

They kept coming, until there was a flock of Cedar Waxwings perched in and around our Winterberry Hollies (Ilex verticillata).

A flock of Cedar Waxwings arrives!
A flock of Cedar Waxwings arrives!

They were here, of course, for the fruit. Cedar Waxwings are especially dependent on fruit in their diet, so much so that ‘Cedar’ in their common name is a nod to Eastern Red Cedar (Juniperus virginiana), whose fruit-like cones are an important source of winter food for this bird. The other part of their common name, ‘Waxwing’, refers to the waxy looking red tips on their secondary wing feathers.

Cedar Waxwing. Notice the red, waxy-looking tips of the secondary wing feathers.
Cedar Waxwing. Notice the red, waxy-looking tips of the secondary wing feathers.

Like most other birds, Cedar Waxwings also eat insects, especially when they are breeding and raising young. I did see one bird take a break from the Winterberry fruit to browse the branches of a nearby Witch-hazel (Hammamelis virginiana) for some insect protein. But fruit was the main attraction for this flock.

Cedar Waxwing reaching for Winterberry Holly (Ilex verticillata fruit
Cedar Waxwing reaching for Winterberry Holly (Ilex verticillata) fruit

While I watched, the birds put on an impressive acrobatic display in pursuit of the delectable fruit.

Cedar Waxwing reaching for Winterberry Holly (Ilex verticillata fruit
Cedar Waxwing reaching for Winterberry Holly (Ilex verticillata) fruit
Cedar Waxwing showing acrobatic talent while reaching for Winterberry Holly (Ilex verticillata fruit
Cedar Waxwing showing flexibility while reaching for Winterberry Holly (Ilex verticillata) fruit

It’s not by accident that such an abundance of fruit is available for these and other birds. The groundwork is laid in late spring, typically June where I am in central New Jersey, when these shrubs produce a wealth of small flowers that are a major attraction for pollinators, including many different species of bees, wasps and flies.     

Perplexing Bumble Bee (Bombus perplexis), visiting a female Winterberry Holly (Ilex verticillata) flower. Her pollination efforts make the fruit that results from this visit possible.
Perplexing Bumble Bee (Bombus perplexis), visiting a female Winterberry Holly (Ilex verticillata) flower. These pollination efforts make the fruit that results from this visit possible.

While they stayed with us, the Cedar Waxwings also ate the remaining Blackhaw Viburnum (Viburnum prunifolium) drupes, as well as some crab apples. The birds moved on after three days, when the trees and shrubs were stripped of their bounty. It was a mesmerizing spectacle while it lasted.  

Cedar Waxwings are typically found in woodland habitats, near water or woods edges, but they are sometimes found in open fields, too. It all depends on food availability. They are sociable birds, and often nest in proximity to other members of their species, with several nests possible in a single ‘neighborhood’.  When they aren’t breeding, they travel in flocks, moving from place to place to find the fruit they need. A few days before the invasion of this flock, I saw one or two Cedar Waxwings in the trees outside.  Because of their gregarious nature, it’s unusual to see a lone bird of this species. Now I can’t help wondering if these early birds were scouts, looking for the next food stop for the group.

To attract Cedar Waxwings to your own yard, be sure to provide the fruit they love.  In addition to Winterberry Holly and Eastern Red Cedar, American Holly (Ilex opaca), Flowering Dogwood (Cornus florida), native viburnums such as Blackhaw (Viburnum prunifolium), Pokeweed (Phytolacca americana), Mountain Ash (Sorbus americana), hawthorns, apples and grapes are all very appealing to this sleek and lovely bird. To see them in summer, offer them blueberries, serviceberries, cherries and blackberries, among other fruit.

Cedar Waxwing eating Winterberry Holly (Ilex verticillata) fruit
Cedar Waxwing eating Winterberry Holly (Ilex verticillata) fruit

Related Posts

Fall Feeding Frenzy

Where Do Winterberries Come From?

Blackhaw Viburnum – A Subtle Beauty

What Do Juniper Hairstreaks and Cedar Waxwings Have in Common?

Resources

All About Birds, the Cornell Lab

Sibley, David Allen. The Sibley Guide to Bird Life & Behavior. 2001.

Enchanter’s Nightshade

Enchanter’s Nightshade (Circaea canadensis), also called Broadleaf Enchanter’s Nightshade, is a small but eye-catching perennial that blooms in early to mid-summer along forest trails. Where I live and play in central New Jersey and Pennsylvania, that means late June through mid-July.

Enchanter’s Nightshade (Circaea canadensis)

This diminutive resident of the forest floor has several pairs of leaves opposite each other along the stem, with a cluster of tiny flowers rising above them. It often grows to about a foot (.4 m), but can reach as much as two feet (.7 m) in height, including the flower cluster (infloresence). The tiny white flowers are only about an eighth of an inch (4 mm) in diameter, and yet in the dim light of summer in the woods they are attention-grabbing, for both humans and pollinators.

Enchanter’s Nightshade (Circaea canadensis)

Each flower has two deeply lobed white petals that look a little like mouse ears, backed by two green, wing-shaped sepals that protected the flower before it opened. Two stamens, the male reproductive parts, reach out like arms from each side at the center of the flower, the anthers at their tips resembling mittened hands. The long narrow structure projecting from the very center of the flower is the pistil, the female reproductive part.  The circular washer-shaped tissue at the base of the pistil is the source of the flower’s nectar, which is offered to entice pollinators to visit.

Enchanter’s Nightshade (Circaea canadensis) flower, with 2 deeply-lobed white petals, 2 stamens reaching out like arms, and one pistil in the center with a circular nectary at its base.

In profile it’s easy to see the veining on the flower’s petals. They are nectar guides, directing pollinators to a potential reward inside.  The stigma reaches out beyond the petals, ready to accept incoming pollen on the stigma at its tip, positioned to be the first thing a pollinator encounters when visiting. The flower’s ovary, covered in hooked hairs, is visible behind the sepals. If pollination is successful, this will ripen to become a small burr-like fruit.

Enchanter’s Nightshade (Circaea canadensis) flower. Notice the veins that act as nectar guides on the petals, the pistil extending beyond the petals, and the hairy ovary behind the green sepals.

The stems of the entire inflorescence are covered with glandular hairs. Hairs on plant tissue usually serve to discourage herbivores from eating the plant, and glandular hairs often have the added benefit of emitting a chemical offense to enhance the deterrent effect.    

Enchanter’s Nightshade (Circaea canadensis) inflorescence. Note that in addition to the flower ovaries, the main stem and flower pedicels (stems) are all covered with glandular hairs, a deterrent to herbivores.

Even such tiny flowers have pollinators who are perfectly matched for them, primarily sweat bees (Halictidae) in the genus Lasioglossum and tiny flower flies, most commonly of the species Toxomerous geminatus. The group of bees called sweat bees get this common name from their habit of obtaining nutrients by licking up human sweat.

Enchanter’s Nightshade (Circaea canadensis) inflorescence, with a sweat bee visiting a flower near the top, and a flower fly perched at the tip of the branch in the lower right.

The bees visit the flowers for both nectar and pollen.  The little sweat bee in the photo below is feeding herself, but also gathering pollen, visible on her hind legs, to bring back to her nest for her larvae. 

Sweat bee, Lasioglossum species, visiting Enchanter’s Nightshade (Circaea canadensis) flower for nectar and pollen. Notice the pollen on her hind legs, which she will bring back to her nest to feed her larvae.
Sweat bee, Lasioglossum species, harvesting pollen from the anther at the tip of the stamen of an Enchanter’s Nightshade (Circaea canadensis) flower

On several occasions, I have watched small swarms of tiny flower flies hovering around Enchanter’s Nightshade flowers.  ‘Hover fly’ is another common name for this group of insects, because of their ability to perform this maneuver. Any individual I was able to see well enough to identify was a Toxomerous geminatus

A flower fly, Toxomerus geminatus, hovering near an Enchanter’s Nightshade (Circaea canadensis) inflorescence

Like the bees, the flies visit the flowers for both nectar and pollen, both of which are important food sources for them.

A flower fly, Toxomerus geminatus, harvesting pollen from an Enchanter’s Nightshade (Circaea canadensis) flower. As it first approached the flower, it came in contact with the stigma at the tip of the pistil, the female reproductive part, before moving on to harvest pollen.
Toxomerus geminatus at rest on a nearby leaf.

After pollination, the flower’s petals, sepals, stamens and pistils wither and fall away, leaving the ovary to ripen to a fruit.

The ovary of an Enchanter’s Nightshade (Circaea canadensis) flower, after its petals, sepals, stamens and pistils have withered and fallen off

As the ovary matures to a fruit, the hooked hairs covering the fruit stiffen, becoming an effective mechanism to grab on to the fur or pants of a passing animal who then unknowingly helps to disperse the seeds. 

Enchanter’s Nightshade (Circaea canadensis) inflorescence with many mature fruits positioned to hitch a ride on the fur or pants of a passing animal.

Enchanter’s Nightshade also has the ability to reproduce through its underground parts, sending up additional shoots to form colonies. 

Why the name Enchanter’s Nightshade?  The Greek goddess and accomplished enchantress Circe reportedly often used potions and herbs to achieve her ends, sometimes turning enemies into other animal species. Plants in this genus, Circaea, were thought to be among the ingredients she used, so were named for her. So far, unfortunately, I haven’t found any of her recipes.   

Enchanter’s Nightshade can be found along forest trails in the United States from Maine west to North Dakota, south as far as Oklahoma, Louisiana, and Georgia, and in Canada from Quebec and Nova Scotia west to Manitoba.  

Take a cooling summer walk in the woods to look for Enchanter’s Nightshade and its pollinators.

Small Enchanter’s Nightshade (Circaea canadensis) colony

Note:  Some sources refer to this species as Circaea lutetiana, Circaea lutetiana L. ssp. canadensis, or Circaea  quadrisulcata.

Resources

Boufford, David E. “The Systematics and Evolution of Circaea (Onagraceae).” Annals of the Missouri Botanical Garden, vol. 69, no. 4, 1982, pp. 804–994. JSTOR,

Global Biodiversity Information Facility (GBIF)

Illinois Wildflowers

Minnesota Seasons.com

Minnesota Wildflowers, copy and paste: https://www.minnesotawildflowers.info/flower/enchanters-nightshade

Niering, William A. The Audubon Field Guide to North American Wildflowers, Eastern Region. 1979.

USDA NRCS Plants Database

Wikipedia

Zakaria Hazzoumi, Youssef Moustakime and Khalid Amrani Joutei (June 24th 2019). Essential Oil and Glandular Hairs: Diversity and Roles, Essential Oils – Oils of Nature, Hany A. El-Shemy, IntechOpen, DOI: 10.5772/intechopen.86571.

Pink Lady’s Slipper – So lovely, so deceptive!

Pink Lady’s Slipper (Cypripedium acaule) emerging from its winter blanket of leaves
Pink Lady’s Slipper (Cypripedium acaule) emerging from its winter blanket of leaves

On a recent trip to Vermont, Pink Lady’s Slipper orchids (Cypripedium acaule), also called Moccasin Flower, were just emerging from their winter blanket of leaves, shyly raising their showy pink blossoms, some still partially obscured by the protective sepal and bract draped over the flowers from above.

Pink Lady’s Slipper orchids (Cypripedium acaule)
Pink Lady’s Slipper orchids (Cypripedium acaule)

Each of these lovely orchid plants has two deeply-veined leaves at its base, from which a single flower stem emerges, topped by a spectacular pink slipper (or moccasin) shaped flower.

Pink Lady’s Slipper orchids (Cypripedium acaule)
Pink Lady’s Slipper orchids (Cypripedium acaule)

Lady’s Slipper orchids have three petals, one that forms the ‘slipper’, while the other two are shaped like slightly curly ribbons or ties, positioned just above the slipper in the perfect location to secure it around a slender ankle. One sepal projects directly above the slipper, adding to the floral display, while two more sepals are fused and extend down the back of the flower. The sepals acted as bud scales protecting the flower before it opened.

Pink Lady’s Slipper orchid (Cypripedium acaule)
Pink Lady’s Slipper orchid (Cypripedium acaule)

Pink Lady’s Slippers invest a lot of energy to produce these lovely flowers to entice pollinators to assist with the cross pollination that the plants are unable to achieve on their own. In addition to their alluring appearance, the flowers produce a mild scent to add to the attraction for insect pollinators. Insects are not altruistic, however. They expect a reward in return for their efforts, in the form of nectar and pollen.

Veining on the flower adds to the attraction, and helps steer potential pollinators to the flower’s entrance at its front. The entrance is also typically highlighted with striping that acts as a directional signal (or nectar guide) for floral visitors.

Pink Lady’s Slipper orchid (Cypripedium acaule). The striped veins direct pollinators to the the flower's entrance at its front.
Pink Lady’s Slipper orchid (Cypripedium acaule). The striped veins direct pollinators to the the flower’s entrance at its front.

The most likely pollinators for Pink Lady’s Slipper are queen Bumble Bees of several species. These bees have the strength required to muscle their way through the narrow slit that offers access to what they anticipate will be a floral reward.

Once inside, however, bees may begin to have second thoughts about the enterprise. The entrance to the flower is one way.  They can’t exit the same way they entered, because the edges of the entryway are curved inward, making an exit impossible. They are trapped inside until they find a different way out, one engineered by the plant to require traversal of a snug passage past the flower’s reproductive parts. The flower’s pistil (female reproductive part) and two fertile stamens (male reproductive parts) are tucked behind the shield-shaped flower part pointing downward at the back of the slipper. This flower part is a modified stamen, called a staminode.

Pink Lady’s Slipper orchid (Cypripedium acaule). Queen Bumble Bees enter the flower through the slit bordered by striped veins in the center of the slipper.
Pink Lady’s Slipper orchid (Cypripedium acaule). Queen Bumble Bees enter the flower through the slit bordered by striped veins in the center of the slipper.

Hairs inside the slipper direct the hapless bee toward the back of the slipper, its reproductive parts, and finally the flower’s exits. There are two possible exits, one on each side of the staminode, and each partially obstructed by an anther from which pollen is dispensed. To get to an exit, the bee first has to brush against the flower’s stigma at the tip of the pistil. This is the spot where pollen must be placed in order for pollination to occur.  If the bee is bringing in pollen, it will be deposited on the stigma as the bee squeezes past it. The exits are within sight now, but before reaching one, the bee will brush against an anther, from which a pollinium (a package with thousands of tiny grains of pollen) will be attached to its back. Then, freedom!

One of two exits available for a bee to escape from a Pink Lady’s Slipper (Cypripedium acaule). The round, cream-colored, seed-like object obstructing the exit is the anther that deposits the pollinia on the bee as it escapes the flower.
One of two exits available for a bee to escape from a Pink Lady’s Slipper (Cypripedium acaule). The round, cream-colored, seed-like object obstructing the exit is the anther that deposits the pollinia on the bee as it escapes the flower.

Throughout this adventure, no nectar was provided to the flower’s visitor. Pollen is an important food for bees, but when it is packaged in pollinia as it is in the Lady’s Slippers, it isn’t accessible for bees to eat. The bees visiting these flowers are seduced by false advertising into assisting the Pink Lady’s Slipper with cross-pollination, but they receive no reward for their efforts. Hopefully, they’ll attempt the quest for food again with another Pink Lady’s Slipper, but it may not take many visits before a bee gets wise to the deception, and stops visiting these flowers.

If Pink Lady’s Slipper’s duplicitous plot succeeds and pollination takes place, a fruit capsule will develop, like those in the photo below. Making the most of this success, each capsule contains thousands of dust-like seeds. In order to obtain the soil nutrients it needs to germinate and grow, each seed needs to find a fungus of the genus Rhizoctonia with which to partner in the location where it lands. Without this partnership, the seeds won’t be viable, and the plant won’t develop. The fungus must be present throughout the Pink Lady’s Slipper’s life to enable the plant’s survival. In return, when the plant is mature enough, it will provide payment to the fungus in the form of carbohydrates.

Pink Lady’s Slipper (Cypripedium acaule) in bloom. At left, mature fruit capsules from successful pollination of a flower from the previous season.
Pink Lady’s Slipper (Cypripedium acaule) in bloom. At left, mature fruit capsules from successful pollination of a flower from the previous season.

Pink Lady’s Slipper is also capable of sending up additional shoots from its rhizome (underground stem), so you may sometimes see it growing in large groups, or colonies.

Colony of Pink Lady’s Slippers
Colony of Pink Lady’s Slippers

The color of the slipper can vary from a deep to pale pink, sometimes even white.

Pink Lady’s Slipper's color can vary from deep to pale pink, sometimes even white.
Pink Lady’s Slipper’s color can vary from deep to pale pink, sometimes even white.

Pink Lady’s Slipper is found in acidic soil in various habitats including deciduous woods or mixed forests of hardwood and coniferous trees, often with pine or hemlock, and in bogs. It is native in Canada in the Northwest Territories and from Alberta to Newfoundland, in the United States from Minnesota to Maine, then south as far as Alabama and South Carolina.  

Pink Lady’s Slipper growing with ferns and Canada Mayflower (Maianthemum canadense)
Pink Lady’s Slipper growing with ferns and Canada Mayflower (Maianthemum canadense)

Look for it blooming near you!      

Pink Lady’s Slipper orchid (Cypripedium acaule) in bloom
Pink Lady’s Slipper orchid (Cypripedium acaule) in bloom

Related Posts

Yellow Lady’s Slipper – Like Winning the Lottery

Resources

USDA Forest Service – Plant of the Week

USDA NRCS Plant Database

North American Orchard Conservation Center

Orchids of the North: the life of the Pink Lady’s Slipper

Davis, Richard W. The Pollination Biology of Cypripedium Acaule (Orchidaceae)

Flora of Newfoundland and Labrador

Minnesota Seasons