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

Where do Winterberries Come From?

It’s difficult to walk past Winterberry Holly (Ilex verticillata) when it’s in fruit without noticing it.  The abundant, vividly red, globular, fleshy fruits of this aptly named shrub never fail to catch the eye.  

Winterberry Holly (Ilex verticillata) in fruit
Winterberry Holly (Ilex verticillata) in fruit

Where do all of those luscious-looking fruits come from?  

Have you ever noticed Winterberry Holly in bloom?

In late spring, Winterberry Holly is covered with an equally large number of somewhat inconspicuous greenish-white flowers. The flowers bloom gradually over a period of a few weeks. 

Like all hollies, Winterberry usually has male and female flowers on separate plants. Only female flowers can develop fruit. Although it isn’t typical, there may occasionally be a specimen with male and female flowers on the same plant, or some flowers that are perfect, that is, they have both male and female parts. Plants often have some variation, as they continue to evolve to try to find the most effective and efficient survival strategies.

Female flowers are usually in small clusters of up to three. The flowers have a single pistil (the female reproductive part) at their center. The green rounded base of the pistil is the ovary. If a flower is successfully pollinated, the ovary will mature, becoming the bright red fruit we see later in the season. The ovary is topped by a stigma, where pollen must be deposited in order for pollination to occur and fruit to develop.

Winterberry Holly (Ilex verticillata) female flowers in bloom.  The whitish specks on the branches are lenticels, through which the plant exchanges gases with the surrounding atmosphere. Lenticels are commonly seen on Winterberry holly branches.
Winterberry Holly (Ilex verticillata) female flowers in bloom. The whitish specks on the branches are lenticels, through which the plant exchanges gases with the surrounding atmosphere. Lenticels are characteristic of Winterberry holly branches.

The white arrow- or spade-shaped projections in between the petals of the female flowers are sterile stamens; they don’t produce pollen that can fertilize the flowers.  It’s likely that they help attract pollinators. As these sterile stamens age, they turn brown.

Winterberry Holly (Ilex verticillata) female flowers in bloom.  The female reproductive part, the pistil, is the green mound-shaped object in the center of the flower.  The ovary is at the base, and will develop into a fruit if pollination is successful and the ovules inside are fertilized. The flat-ish tissue at the top is the stigma, where pollen must be placed by an incoming bee or other pollinator.  The white arrow- or spade-shaped projections in between the petals are sterile stamens.
Winterberry Holly (Ilex verticillata) female flowers in bloom. The female reproductive part, the pistil, is the green volcano-shaped object in the center of the flower. The ovary is the base of the volcano, and will develop into a fruit if pollination is successful and the ovules inside are fertilized. The flat-ish tissue at the top is the stigma, where pollen must be placed by an incoming bee or other pollinator. The white arrow- or spade-shaped projections in between the petals are sterile stamens.

Male flowers often bloom in crowded clusters of up to 10 or more.  The male reproductive parts, called stamens, reach upward from the face of the flower, the anthers at their tips ready to deposit pollen on a flower visitor.   

Winterberry Holly (Ilex verticillata) male flowers, blooming in densely-packed clusters.
Winterberry Holly (Ilex verticillata) male flowers, blooming in densely-packed clusters.
Winterberry Holly (Ilex verticillata) male flowers in bloom. The male reproductive parts, called stamens, reach up from the face of the flowers.  Pollen is produced from the anthers at their tips.
Winterberry Holly (Ilex verticillata) male flowers in bloom. The male reproductive parts, called stamens, reach up from the face of the flowers. Pollen is produced from the tan anthers at their tips.

Winterberry Holly needs third party assistance to move pollen from a male flower on one plant to a female flower on another plant, in order to achieve pollination. It may be easy for people to walk past without noticing when these shrubs are in bloom, but fortunately the flowers are enticing beacons to potential pollinators of many different species, especially bees. A recent study showed Winterberry Holly to be among the most attractive to bees of the flowering shrubs.

In my own garden I spotted Bumble Bees, Mining Bees, Sweat Bees, Small Carpenter Bees and a wasp visiting the flowers for nectar rewards. Bees also eat pollen, and female bees may collect pollen to feed their larvae.

Confusing or Perplexing Bumble Bee (Bombus perplexus) visiting a Winterberry Holly (Ilex verticillata) female flower.
Confusing or Perplexing Bumble Bee (Bombus perplexus) visiting a Winterberry Holly (Ilex verticillata) female flower.
Mining Bee with a Winterberry Holly (Ilex verticillata) flower.
Mining Bee drinking nectar from a Winterberry Holly (Ilex verticillata) flower.
Sweat Bee with a Winterberry Holly (Ilex verticillata) female flower.
Sweat Bee visiting a Winterberry Holly (Ilex verticillata) female flower.
Small Carpenter Bee (Ceratina species) departing from a Winterberry Holly (Ilex verticillata) flower.
Small Carpenter Bee (Ceratina species) departing from a Winterberry Holly (Ilex verticillata) female flower.
Eastern yellow Jacket drinking from a Winterberry Holly (Ilex verticillata) female flower.
Eastern Yellow Jacket drinking from a Winterberry Holly (Ilex verticillata) female flower.

Without the assistance of these flower visitors, pollination would not take place, no fruit would develop, and Winterberry Holly would not be able to reproduce. If these pollinators do the job the plants have enticed them to do, fruit develops, ripening by fall.

Winterberry Holly (Ilex verticillata) in fruit.
Winterberry Holly (Ilex verticillata) in fruit.

Birds are the primary target audience for the colorful display of Winterberry Holly’s bright red fruit. Many different species of birds including Eastern Bluebirds,

Eastern Bluebirds enjoy Winterberry Holly (Ilex verticillata) fruit
Eastern Bluebirds enjoy Winterberry Holly (Ilex verticillata) fruit

White-throated Sparrows,

White-throated Sparrows are among the birds that eat Winterberry Holly (Ilex verticillata) fruit.
White-throated Sparrows are among the birds that eat Winterberry Holly (Ilex verticillata) fruit.

and Hermit Thrush

Hermit Thrush sitting in a Winterberry Holly (Ilex verticillata)
Hermit Thrush in a Winterberry Holly (Ilex verticillata)

eat the fleshy fruit and later become the unwitting dispersers of the seeds inside as they deposit them with natural fertilizer when defecating.

Small mammals like mice and squirrels may eat Winterberry fruit, too. People are just the accidental beneficiaries of the bright spectacle, but shouldn’t eat the fruit, which is toxic to humans.

Winterberry Holly fruits contain more carbohydrates than fats, making them less preferred by birds than some other fruit available in the fall. As a result, Winterberry fruit is frequently passed over until later in the season, often well into winter, although sometimes a flock of hungry American Robins or Cedar Waxwings will strip a Winterberry Holly of all its fruit in a matter of hours.

American Robin in Winterberry Holly (Ilex verticillata).  A flock of hungry Robins can strip a shrub of its fruit in a matter of hours.
American Robin in Winterberry Holly (Ilex verticillata). A flock of hungry Robins can strip a shrub of its fruit in a matter of hours.

Winterberry Holly is a deciduous shrub or understory tree that grows to a maximum height of about 15 – 20 feet (5 – 6 meters). It prefers moist soil, and is indigenous in bogs and wet woods in the eastern half of the United States and Canada. It makes a great addition to your own landscape for its benefit to pollinators, birds and other wildlife. It doesn’t hurt that Winterberry Holly adds some bright color to a winter landscape.

Winterberry Holly (Ilex verticillata) in fruit.
Winterberry Holly (Ilex verticillata) in fruit.

Resources

Eastman, John.  The Book of Swamp and Bog.  1995.

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

Mach, Bernadette M.; Potter, Daniel A. Quantifying bee assemblages and attractiveness of flowering woody landscape plants for urban pollinator conservation. 2018.

Rhoads, Ann Fowler; Block, Timothy A.  The Plants of Pennsylvania.  2007

Williams, Paul; Thorp, Robin; Richardson, Leif; Colla, Sheila. Bumble Bees of North America. 2014.

Wilson, Joseph S.; Carril, Olivia Messinger.  The Bees in Your Backyard. 2016.

Illinois Wildflowers

Minnesota Wildflowers

Missouri Botanical Garden Plant Finder

USDA NRCS Plant Database