Northern Prickly-ash

I saw my first Northern Prickly-ash (Zanthoxylum americanum) on a walk through the woods in winter. The plentiful prickles along the branches and trunk

Northern Prickly-ash (Zanthoxylum americanum) branch with prickles

Northern Prickly-ash (Zanthoxylum americanum) branch with prickles

and the unusual fruit caught my eye.

Northern Prickly-ash (Zanthoxylum americanum) with ripe fruit

Northern Prickly-ash (Zanthoxylum americanum) with ripe fruit

Northern Prickly-ash is certainly prickly, but it isn’t an Ash at all. It does have compound leaves that resemble those of the Ashes (Fraxinus species), but that’s just a superficial resemblance.  Based on the structure of its flowers, Northern Prickly-ash has been classified as a member of the Rue (Rutaceae) family of plants, which is also called the Citrus family.

Like other members of the Rue family, Northern Prickly-ash’s foliage is covered with glands that are fragrant when crushed, emitting a somewhat lemon-like scent. Northern Prickly-ash blooms in spring before its leaves emerge, with male and female flowers usually on separate plants. The flowers are tiny, but they are fragrant, and attract a variety of bees and flies to visit.

By June, if the flowers were successfully pollinated by their visitors, a Northern Prickly-ash with female flowers will have fruit. Bobwhites, Red-eyed Vireos and Chipmunks are among the animals that eat the fruit.

Eastern Chipmunks may eat Northern Prickly-ash (Zanthoxylum americanum) fruit

Eastern Chipmunks may eat Northern Prickly-ash (Zanthoxylum americanum) fruit

While the fruit looks like a berry, but it is actually a follicle, a dry (not fleshy) fruit that splits open along a single seam. The fruit is green in early summer.

Northern Prickly-ash (Zanthoxylum americanum) with unripe fruit

Northern Prickly-ash (Zanthoxylum americanum) with unripe fruit

On its way to fully ripening it turns red.

Northern Prickly-ash (Zanthoxylum americanum) with fruit in autumn

Northern Prickly-ash (Zanthoxylum americanum) with fruit in autumn

By late fall or winter, the follicle ripens, turning brown, then splits open to reveal the seeds, usually one seed, or at most two per follicle.

Northern Prickly-ash (Zanthoxylum americanum) fruit in late winter

Northern Prickly-ash (Zanthoxylum americanum) fruit in late winter

Not many insects eat the foliage of Northern Prickly-ash. The leaves contain toxic chemicals (furanocoumarins) that are a deterrent to herbivores. But the caterpillars of Giant Swallowtail butterflies specialize on the leaves of the Rue family members.  They have evolved to be able to ingest the toxins and sequester them in their bodies without experiencing any harmful effects.  Throughout the Giant Swallowtail’s life, from caterpillar to pupa to butterfly, these toxins protect them from being eaten by predators.  This is the same type of relationship that Monarch butterflies have with Milkweeds (Asclepias species).  Monarchs have evolved to specialize on Milkweeds as the only food their caterpillars can eat in exchange for the protection the plants’ toxins give them.

Plants and people have more in common than you might think. Both have mutually beneficial relationships with some fungi and bacteria (think of the good bacteria in your digestive system, and edible and medicinal mushrooms), and adversarial relationships with others that may cause disease.  Many plants have evolved to produce chemical compounds to defend against the predatory fungi, bacteria or microbes that might invade their tissues.  Sometimes those chemicals can also be beneficial to humans in treating diseases with similar causes.

Studies show that Northern Prickly-ash contains compounds with anti-fungal properties, and compounds that have cancer-fighting potential. Native North American medical traditions have long recognized the potential of Northern Prickly-ash for treating disease, using it for many purposes, including as an antirheumatic and pain reliever, for treating coughs, colds and pulmonary problems, heart problems, kidney problems, and Tuberculosis.  One of the most well-known medical applications for Northern Prickly-ash is the use of the inner bark as a toothache remedy, giving this tree another common name, Toothache-tree.

Northern Prickly-ash is native as far north as Quebec and Ontario, and south as far as Oklahoma, Louisiana and Florida, although it is rarer in the southeastern United States. It prefers moist well-drained soils, and can tolerate full sun to part shade.  Northern Prickly-ash can be found on stream banks and in wet woods, sometimes creating a thicket by reproducing through underground runners.

Mature Northern Prickly-ash (Zanthoxylum americanum) trunk and branches, with prickles

Mature Northern Prickly-ash (Zanthoxylum americanum) trunk and branches, with prickles

Winter is a good time to look for Northern Prickly-ash.  Take a walk and see if you can find its distinctive prickles and fruit.

Related Posts

Milkweed – It’s Not Just for Monarchs

What Winter Reveals: Hoptrees

Black Cherry – For Wildlife, and People, too!

Slippery Elm in Bloom

Resources

Cech, Rick; Tudor, Guy. Butterflies of the East Coast.  2005.

Foster, Steven; Duke, James A. A Field Guide to Medicinal Plants and Herbs of Eastern and Central North America.  2000.

Moerman, Daniel E. Native American Ethnobotany.  1998.

Nelson, Gil; Earle, Christopher J.; Spellenberg, Richard. Trees of Eastern North America.  2014.

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

Missouri Botanical Garden

USDA Plant Database

Illinois Wildflowers

Lady Bird Johnson Wildflower Center

U.S. National Library of Medicine National Institutes of Health:

https://www.ncbi.nlm.nih.gov/pubmed/15957372

https://www.ncbi.nlm.nih.gov/pubmed/11507740

 

 

To Love Winter: Striped Wintergreen

It may be winter in the northern hemisphere (at least some days), but there is still plenty to see if you go for a walk in the woods. Some plants may be easier to spot in winter than they are during the growing season, because they have less competition for light, and for your attention.  Striped Wintergreen (Chimaphila maculata) is one of those plants.  Striped Wintergreen can be seen in woodlands, skimming just above the fallen leaves.

Striped Wintergreen (Chimaphila maculata) in fruit

Striped Wintergreen (Chimaphila maculata) in fruit

A clue that winter is the perfect time to look for this plant is found in the translation of its genus, ‘Chimaphila’, whose origins are the Greek words ‘cheima’, which means ‘winter’ and ‘phileo’, which translates as ‘to love’.   Plants of this genus are named for their love of winter.

Striped Wintergreen (Chimaphila maculata)

Striped Wintergreen (Chimaphila maculata)

Why do they love winter? Striped Wintergreen is an evergreen perennial of the forest understory, growing to a height of about 4 – 12 inches (10 – 30 cm).  Somewhat woody at the base of the stem, botanists classify this species as a shrub or subshrub.  Its green and white striped leaves make it easy to spot in the winter months when leaves have fallen from the deciduous trees and shrubs that tower over this diminutive plant.  During the growing season, its taller neighbors often obscure Striped Wintergreen from view, as well as from the sun’s rays.  But throughout winter, Striped Wintergreen’s evergreen leaves have unfettered access to the sun’s energy.  They can photosynthesize, store the energy, and make it available to support Striped Wintergreen’s summertime reproductive efforts.

Striped Wintergreen is known by many other aliases (common names), including Spotted Wintergreen, Pipsissewa, and Rheumatism Root. Some of these names refer to the medicinal uses of this plant. Striped Wintergreen contains chemical compounds with antiseptic, antibacterial, and astringent properties, among others.  One of the compounds, ursolic acid, is effective in treating arthritis and other causes of pain and inflammation.  Striped Wintergreen and a close relative that is also called Pipsissewa (Chimaphila umbellata) have been used to treat urinary tract infections and kidney stones.  The name Pipsissewa is derived from a Creek Native American word that means ‘to break into small pieces’, referring to stones in the urinary tract.

Is it just lucky happenstance that Striped Wintergreen contains compounds that have beneficial medicinal effects for humans? Not completely.  Striped Wintergreen faces some of the same pressures that humans do from bacteria, fungi and microbes, all of which are present in the thousands in the fallen leaves with which Striped Wintergreen lives, and that are working to break down the leaves until they become the next layer of nutrient-filled soil.  Striped Wintergreen has evolved to produce chemical compounds to protect itself from this efficient recycling team surrounding it.  What is lucky for us is that these chemical constituents also have a positive effect in human bodies.

Striped Wintergreen blooms in summer, usually sometime from June through August.

Striped Wintergreen (Chimaphila maculata) in bloom. Fruit capsule from previous season is visible on the left.

Striped Wintergreen (Chimaphila maculata) in bloom. Fruit capsule from previous season is visible on the left.

When fully open, the flowers with their recurved petals resemble crowns, a possible explanation for another common name for this plant, Striped Prince’s Pine.

Striped Wintergreen (Chimaphila maculata) flower. Notice its resemblance to a tiny crown.

Striped Wintergreen (Chimaphila maculata) flower. Notice its resemblance to a tiny crown.

Striped Wintergreen’s primary pollinators are Bumble Bees (Bombus species), but Honey Bees (Apis mellifera) may also be enticed by nectar to visit the flowers.  If the bees help Striped Wintergreen successfully achieve pollination, the resulting fruit is visible throughout the winter.  These dry fruit capsules look like tiny turbans, or miniature winter squash split open at the seams to release the seeds inside.

Striped Wintergreen (Chimaphila maculata) fruit capsules.

Striped Wintergreen (Chimaphila maculata) fruit capsules.

The chemical compounds present in Striped Wintergreen, along with leathery, waxy-coated leaves, are generally effective in deterring herbivores. Deer don’t typically browse this plant, even though it’s one of only a few that are green in the winter.  But the photo below shows that someone, probably a Leaf-cutter Bee (Megachile species), has figured out a way to use parts of the leaves.  Leaf-cutter bees harvest regularly-shaped oval, circular or semi-circular pieces of leaves to construct cells in their nests.

Striped Wintergreen (Chimaphila maculata) with semi-circles removed from the leaf edges, probably by a Leaf-cutter Bee.

Striped Wintergreen (Chimaphila maculata) with semi-circles removed from the leaf edges, probably by a Leaf-cutter Bee.

Striped Wintergreen’s native range is the eastern third of the United States, north to a few locations in southern Ontario and Quebec provinces in Canada. It’s rare at the edges of its range, and is listed as endangered in Illinois, Maine, Ontario and Quebec, and exploitably vulnerable in New York state.

Experience some ‘Winter Love’ (another common name for Chimaphila maculata).  Look for Striped Wintergreen in winter, and you’ll know where to find it during the summer months when it’s in bloom.

Striped Wintergreen (Chimaphila maculata) in bloom.

Striped Wintergreen (Chimaphila maculata) in bloom.

More Reasons to Love Winter

Reasons to Love Winter

An Orchid in Winter

Coralberry – A Winter Standout

What Winter Reveals:  Hoptrees

Late Winter Bird Food

A Winter Garden Can Be a Wildlife Habitat

Resources

Buhner, Stephen Harrod. Pipsissewa.  From Planting the Future, Saving Our Medicinal Herbs, edited by Gladstar, Rosemary and Hirsch, Pamela.  2000.

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

Eiseman, Charley; Charney, Noah. Tracks & Sign of Insects and Other Invertebrates. 2010.

Foster, Steven; Duke, James A. A Field Guide to Medicinal Plants and Herbs of Eastern and Central North America.  2000.

Martin, Laura C. Wildflower Folklore.  1984.

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

Evergreen Native Plant Database

Illinois Wildflowers

Lady Bird Johnson Wildflower Center

Native American Ethnobotany Database

USDA NRCS Plants Database

 

 

A Holiday Break

If you feel the need for a little break from all the holiday shopping and festivities, I recommend a walk in the woods.

If the ground isn’t snow-covered, you might look for Patridgeberry (Mitchella repens) while you are out walking. It’s a low evergreen perennial that creeps across the forest floor, resembling strings of tiny holiday garlands.

Patridgeberry (Mitchella repens)

Patridgeberry (Mitchella repens)

Patridgeberry may be peeking out from under fallen leaves.

Patridgeberry (Mitchella repens)

Patridgeberry (Mitchella repens)

Look closely at a patch of moss, and you might find Patridgeberry interspersed with it.

Patridgeberry (Mitchella repens) mixed with mosses

Patridgeberry (Mitchella repens) mixed with mosses

Patridgeberry’s bright red fruit usually persists on the plant throughout the winter and even into spring.

Patridgeberry (Mitchella repens) in spring, with fruit from the previous year still present.

Patridgeberry (Mitchella repens) in spring, with fruit from the previous year still present.

It may actually be easier to find Patridgeberry in the winter than it is during the growing season, depending on its situation. This diminutive ground cover may be hidden by taller herbaceous plants and shrubs in the late spring when it begins to bloom.  If you find it in winter, you’ll know where to look to see the flowers, probably sometime in late May or June.

Patridgeberry (Mitchella repens) in bloom, partially hidden by taller plants

Patridgeberry (Mitchella repens) in bloom, partially hidden by taller plants

Bumble Bees are the primary pollinators of Patridgeberry’s tiny trumpet-shaped flowers. The flowers are always in pairs; in fact, they are actually joined.

Patridgeberry's (Mitchella repens) paired flowers in bloom.

Patridgeberry’s (Mitchella repens) paired flowers in bloom.

The two flowers share a single ovary, the part of the flower from which a fruit develops.  As a result, no more than one berry is produced for every pair of flowers.  You might think of this as analogous to conjoined twins that share a body part.  In recognition of this trait, another common name for this plant is Twinberry.  If you look closely at the fruit in the photo below, you can see two dimples, each with a somewhat jagged edge.  This is where each individual flower was joined to the ovary.

Patridgeberry (Mitchella repens) fruit. Notice the jagged edged 'dimples' where the two flowers were attached to their shared ovary.

Patridgeberry (Mitchella repens) fruit. Notice the jagged edged ‘dimples’ where the two flowers were attached to their shared ovary.

Wild Turkey, Ruffed Grouse, Bobwhite, White-footed Mice, Red Fox and Eastern Chipmunks are among the animals that eat Patridgeberry fruits. The animals subsequently disperse Patridgeberry’s seeds, which are accompanied by natural fertilizer (the animal’s excrement) to give the seeds a good start.

Native American tribes have used various parts of Patridgeberry, sometimes in combination with other plants, as a gynecological aid and pain reliever, as well as to treat rashes and urinary tract problems, among other problems.

Patridgeberry can be found in the woods of the eastern half of the United States, and in the Canadian provinces of Ontario, Quebec, New Brunswick, Nova Scotia, and parts of Newfoundland & Labrador.

For the holidays, do whatever best renews your spirit. A walk in the woods will do it for me.

If the ground is snow-covered, there will be other holiday decorations to see, courtesy of nature. Nothing you have to put up, or take down.  No muss, no fuss.  Just beauty.

Patridgeberry (Mitchella repens) mixed with mosses and mushrooms

Patridgeberry (Mitchella repens) mixed with mosses and mushrooms

Related Posts

A Holiday Display, Courtesy of Nature

Resources

Capon, Brian. Botany for Gardeners.  2005

Foster, Steven; Duke, James A. A Field Guide to Medicinal Plants and Herbs of Eastern and Central North America.  2000.

Hoffmann, David. Medical Herbalism.  2003.

Martin, Alexander C.; Zim, Herbert S.; Nelson, Arnold L. American Wildlife & Plants A Guide to Wildlife Food Habits.  1951.

Moerman, Daniel E. Native American Ethnobotany.  1998.

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

Illinois Wildflowers

Missouri Botanical Garden

USDA NRCS Plant Database

 

Jewelweed Has a Back-up Plan

Jewelweed leaves emerge from the soil in early spring, the plant continuing to grow and mature until it finally begins to bloom in mid-to-late summer, and on through early fall. The name ‘Jewelweed’ has a few explanations, but the one I like best is that it’s a reflection of the fact that the surface of Jewelweed leaves causes water to bead up, glistening like a jewel.

Jewelweed (Impatiens capensis) with Sweat Bee (Halictid species). Notice the jewel-like drops and silvery sheen of water on the leaves.

Jewelweed (Impatiens capensis) with Sweat Bee (Halictid species). Notice the jewel-like drops and silvery sheen of water on the leaves.

There are two Jewelweed species that are common in eastern North America. One has orange flowers with dark reddish-orange spots or lines at the throat.  Some common names for this orange-flowered species are Jewelweed, Spotted Jewelweed, or Spotted Touch-me-not (Impatiens capensis).

Jewelweed or Spotted Touch-me-not (Impatiens capensis)

Jewelweed or Spotted Touch-me-not (Impatiens capensis)

The other species has yellow flowers, sometimes with reddish-brown dots at the throat, and is known as Pale Jewelweed, Yellow Jewelweed or Pale Touch-me-not (Impatiens pallida).

Pale Jewelweed or Pale Touch-me-not (Impatiens pallida)

Pale Jewelweed or Pale Touch-me-not (Impatiens pallida)

These Jewelweed species are annuals, meaning that each plant dies at the end of the growing season. In order for the species to continue to survive, it must produce seeds each year.  Jewelweed has two strategies to make sure that happens.

Jewelweed’s primary strategy for reproduction is to produce showy flowers that will entice animals to visit, and transfer pollen from one plant to another, successfully achieving cross-pollination.

Jewelweed (Impatiens capensis) with Bumble Bee (Bombus species)

Jewelweed (Impatiens capensis) with Bumble Bee (Bombus species)

When Jewelweed flowers open, their male reproductive parts (the stamens), mature first, making pollen available for transfer from the anthers at the stamen tips.

Pale Jewelweed (Impatiens pallida) with mature stamens at the inside top of the entrance of the blossom

Pale Jewelweed (Impatiens pallida) with mature stamens at the inside top of the entrance of the blossom

Later, the stamens wither and are replaced by the female reproductive parts (the pistils), the receptive stigmas at their tips waiting for a flower visitor to brush them with pollen.

Jewelweed (Impatiens pallida) with mature pistil at the inside top of the entrance of the blossom. (Being visited by a mystery critter!)

Jewelweed (Impatiens pallida) with mature pistil at the inside top of the entrance of the blossom. (Being visited by a mystery critter!)

Jewelweed’s showy flowers produce plenty of nectar to lure potential pollinators to visit. The nectar is found in long spurs at the back of the tubular flowers, so a visitor with a long tongue is most likely to have success accessing this treat.  The orange-flowered Jewelweed attracts a broad variety of insect visitors, including several bee species,

Jewelweed (Impatiens capensis) with Bumble Bee (Bombus species)

Jewelweed (Impatiens capensis) with Bumble Bee (Bombus species)

Jewelweed (Impatiens capensis) with Yellow Bumble Bee (Bombus fervidus)

Jewelweed (Impatiens capensis) with Yellow Bumble Bee (Bombus fervidus)

Jewelweed (Impatiens capensis) with Honey Bee

Jewelweed (Impatiens capensis) with Honey Bee

Jewelweed (Impatiens capensis) with Sweat Bee (Agapostemon species)

Jewelweed (Impatiens capensis) with Sweat Bee (Agapostemon species)

Jewelweed (Impatiens capensis) with Sweat Bee (Halictid species)

Jewelweed (Impatiens capensis) with Sweat Bee (Halictid species)

flies,

Jewelweed (Impatiens capensis) with Flower Fly (Copestylum species)

Jewelweed (Impatiens capensis) with Flower Fly (Copestylum species)

Jewelweed (Impatiens capensis) with Flower Fly (Syrphid species)

Jewelweed (Impatiens capensis) with Flower Fly (Syrphid species)

wasps,

Jewelweed (Impatiens capensis) with Yellowjacket

Jewelweed (Impatiens capensis) with Yellowjacket

and even beetles.

Jewelweed (Impatiens capensis) with Northern Corn Rootworm Beetles

Jewelweed (Impatiens capensis) with Northern Corn Rootworm Beetles

Jewelweed (Impatiens capensis) with beetle, probably Spotted Cucumber Beetle

Jewelweed (Impatiens capensis) with beetle, probably Spotted Cucumber Beetle

These beetles are interested in consuming floral tissue, and are probably not very helpful in assisting Jewelweed in attaining its pollination goal.

Given their anatomy and feeding style, Bumble Bees are among the most likely to help successfully pollinate the flowers. They are the most frequent visitors to Pale Jewelweed.

Pale Jewelweed (Impatiens pallida) with Bumble Bee (Bombus species), at Morrisville Riverfront Preserve, Morrisville, PA

Pale Jewelweed (Impatiens pallida) with Bumble Bee (Bombus species), at Morrisville Riverfront Preserve, Morrisville, PA

Pale Jewelweed (Impatiens pallida) with Bumble Bee (Bombus species) with back brushing stamens as it enters the flower, at Morrisville Riverfront Preserve, Morrisville, PA

Pale Jewelweed (Impatiens pallida) with Bumble Bee (Bombus species) with back brushing stamens as it enters the flower, at Morrisville Riverfront Preserve, Morrisville, PA

Even in the insect world there are individuals who like to cut corners and get something for nothing.  There are insects that cheat, chewing through the spur to directly access the nectar. These insects by-pass the flower opening and its reproductive parts, so they’re no help to Jewelweed in its pollination mission.

Ruby-throated Hummingbirds are valuable pollination partners for Jewelweed. As these energetic little birds move from one Jewelweed flower to another, they are likely to pick up pollen on their heads as they brush against the anthers at the inside top of the flower entrance, subsequently depositing the pollen on the stigma of another flower.  In return, Jewelweed provides an important nectar source for them in late summer and early fall.

Male Ruby-throated Hummingbird

Male Ruby-throated Hummingbird

The name ‘Touch-me-not’ reflects the explosive spring-action opening of ripe fruit capsules. The slightest touch will trigger it, projecting the seeds for a distance of several feet.

Ripe Pale Jewelweed fruit capsule

Ripe Pale Jewelweed fruit capsule

The ripe capsule opens at the slightest touch

The ripe capsule opens at the slightest touch

Animal seed eaters include Ruffed Grouse, Bobwhites, mice and shrews.

Jewelweed also has a back-up plan for producing seed, one that doesn’t rely on the assistance of a third party for pollen transportation. In addition to the showy flowers that entice pollinators, Jewelweed produces cleistogamous flowers, a type of flower that doesn’t open and is self-fertilized. When the fruit capsules produced from these flowers open, the seeds fall in the vicinity of the parent plant.  The combination of the two types of flowers may allow Jewelweed to hold its existing territory, and extend it a bit.

Jewelweed contains lawsone, a compound with antihistamine and anti-inflammatory properties. Jewelweed has been used to treat poison ivy exposure, and stings from stinging nettle and insects.

Jewelweed prefers moist soil, and is often found along streams, in wet meadows, roadsides, swamps and open woods.

Jewelweed (Impatiens capensis ) at Wiessner Woods, Stowe, Vermont

Jewelweed (Impatiens capensis ) at Wiessner Woods, Stowe, Vermont

It may establish a large colony, with individual plants often growing to a height of 5 feet (1.5 meters).

Jewelweed (Impatiens capensis ) at Wiessner Woods, Stowe, Vermont

Jewelweed (Impatiens capensis ) at Wiessner Woods, Stowe, Vermont

The orange-flowered Jewelweed’s (Impatiens capensis) range includes the eastern two-thirds of the United States plus Idaho, Oregon and Washington, and all Canadian provinces and territories, except Nunavit.  Pale Jewelweed (Impatiens pallida) is less common, and more of an eastern species.  It can be found from Newfoundland and Labrador, west to Ontario and eastern North Dakota, and as far south as eastern Oklahoma and South Carolina.

 

Resources

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

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

Evans, Arthur V. Beetles of Eastern North America.  2014.

Foster, Steven; Duke, James A. A Field Guide to Medicinal Plants and Herbs of Eastern and Central North America.  2000.

Moerman, Daniel E. Native American Ethnobotany.  1998.

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

Colla, Sheila; Richardson, Leif; Williams, Paul. Bumble Bees of the Eastern United States. 2011

USDA Forest Service Plant of the Week – Jewelweed

Illinois Wildflowers

USDA NRCS Plant Database Impatiens capensis

USDA NRDS Plant Database Impatiens pallida

 

 

 

Who Uses Black Cohosh?

Black Cohosh (Actaea racemosa, synonym Cimicifuga racemosa) blooms in mid-summer, lighting up the forest understory.

Black Cohosh (Actaea racemosa, syn. Cimicifuga racemosa)

Black Cohosh (Actaea racemosa, syn. Cimicifuga racemosa)

The spikes of white flowers seem to glow even in the dark, begging to be called Fairy Candles, one of the other common names by which Black Cohosh is known.

Black Cohosh (Actaea racemosa, syn. Cimicifuga racemosa)

Black Cohosh (Actaea racemosa, syn. Cimicifuga racemosa)

Black Cohosh flowers are arranged in long narrow clusters called racemes, blooming from the bottom of the flower stalk to the top. Each individual flower looks like a pom-pom, formed by an aggregation of many stamens (the male reproductive parts) surrounding a single pistil (the female reproductive part).

Black Cohosh (Actaea racemosa, syn. Cimicifuga racemosa) flowers

Black Cohosh (Actaea racemosa, syn. Cimicifuga racemosa) flowers

Black Cohosh depends on the assistance of animals to achieve pollination. The flowers are visited by many species of insects whose bodies may come in contact with pollen dispensed from anthers at the tips of the stamens.  Some of that pollen may adhere to the insect’s body.  When the insect moves to a flower of another Black Cohosh plant and brushes against the flower’s stigma (the receptive part of the pistil), then Black Cohosh’s pollination goal is achieved.

It’s not an accident that insects visit the flowers. Plants and animals have evolved together over centuries to depend on each other.  About 80% of flowering plants depend on animals to carry their pollen to other plants of the same species, helping them achieve successful cross-pollination.  In exchange, many animals depend exclusively, or for at least part of their diet, on plants.

The most common food enticements that plants offer to flower visitors are nectar and pollen. Many insects visit flowers for nectar, but some are also interested in eating pollen, and in the case of bees, harvesting it to bring back to their nests to feed their larvae.

Black Cohosh has evolved a strategy of offering pollen, but not nectar, to entice potential pollinators. Plants evolve to be as efficient as possible, trying not to expend unnecessary resources.  Black Cohosh is able to attract enough visitors to its flowers by offering them pollen only.

Insects want to eat pollen and plants want insects to transport their pollen to another plant of the same species. If this sounds like a potential conflict of interest, it is.  Only about 2% of pollen is actually used for pollination.  Potential pollinators or their offspring eat much of the remaining 98%.

In spite of the fact that another common name for Black Cohosh is Bugbane, many insects are more attracted than deterred by its fragrance. Bees, flies and beetles visit Black Cohosh flowers to eat or harvest pollen.  While I watched for just a few minutes, the activity at a small group of Black Cohosh plants included bees, flies and beetles.  Bumble Bees, Sweat Bees, and Leaf-cutter Bees, all worked the flowers.

Black Cohosh (Actaea racemosa, syn. Cimicifuga racemosa) with Leafcutter bee (Megachile species)

Black Cohosh (Actaea racemosa, syn. Cimicifuga racemosa) with Leafcutter bee (Megachile species)

Black Cohosh (Actaea racemosa, syn. Cimicifuga racemosa) with Sweat bee (Haictidae)

Black Cohosh (Actaea racemosa, syn. Cimicifuga racemosa) with Sweat bee (Haictidae)

Bumble Bee visits were the most brief. They stopped for just a few seconds per plant before moving on to another.  It may seem counterintuitive, but this may make Bumble Bees the most successful of Black Cohosh’s cross-pollinators, since they are the most likely to move the pollen to a different plant.

A Flower or Syrphid Fly (Toxomerus geminatus) dined on the flowers’ pollen.

Black Cohosh (Actaea racemosa, syn. Cimicifuga racemosa) with Flower Fly (Toxomerus geminatus)

Black Cohosh (Actaea racemosa, syn. Cimicifuga racemosa) with Flower Fly (Toxomerus geminatus)

At least two species of tiny Tumbling Flower Beetles (Falsomordellistena pubescens and Mordellistena fuscipennis) munched on the flowers’ tissues.    Tumbling Flower Beetles are named for their behavior when threatened; they bounce and tumble unpredictably and may fly away, carrying pollen to another plant, possibly helping to meet Black Cohosh’s pollination needs.

Black Cohosh (Actaea racemosa, syn. Cimicifuga racemosa) with Tumbling Flower Beetle (Falsomordellistena pubescens) in upper right

Black Cohosh (Actaea racemosa, syn. Cimicifuga racemosa) with Tumbling Flower Beetle (Falsomordellistena pubescens) in upper right

The Tumbling Flower Beetles were joined by at least three species of Longhorn Beetles, the Banded Longhorn Beetle (Typocerus velutinus), and two others, Metacmaeops vittata, and Analeptura lineola.

Black Cohosh (Actaea racemosa, syn. Cimicifuga racemosa) with Longhorn Beetle (Metacmaeops vittata), upper right, and Tumbling Flower Beetles (Mordellistena fuscipennis)

Black Cohosh (Actaea racemosa, syn. Cimicifuga racemosa) with Longhorn Beetle (Metacmaeops vittata), upper right, and Tumbling Flower Beetles (Mordellistena fuscipennis)

Black Cohosh (Actaea racemosa, syn. Cimicifuga racemosa) with Longhorn Beetle (Analeptura lineola), center, and Tumbling Flower Beetle (Mordellistena fuscipennis)

Black Cohosh (Actaea racemosa, syn. Cimicifuga racemosa) with Longhorn Beetle (Analeptura lineola), center, and Tumbling Flower Beetle (Mordellistena fuscipennis)

For an insect, visiting Black Cohosh flowers is not without its risks. Predators like the perfectly camouflaged Crab Spider in the photo below may be lurking in the shadows, waiting for an unwary victim.

Crab Spider with a fly victim (upper left), bee and Tumbling Flower Beetle on Black Cohosh (Actaea racemosa, syn. Cimicifuga racemosa)

Crab Spider with a fly victim (upper left) on Black Cohosh (Actaea racemosa, syn. Cimicifuga racemosa) with bee and Tumbling Flower Beetle

Black Cohosh is the only food Appalachian Azure butterfly caterpillars can eat. Female butterflies lay their eggs on flower buds.  When the caterpillars hatch, they begin eating the buds and flowers, moving on to leaves if no flowers remain.  Like the other Azure butterfly caterpillars, the Appalachian Azure caterpillars are protected by ants in exchange for the delicious honeydew the caterpillars excrete.  Depending on the species, ants have different forms of defensive weapons; they may bite, sting, or spray an acid at their enemy targets, deterring even birds from their prey.

Appalachian Azure caterpillar being tended by ants, on Black Cohosh (Actaea racemosa) flower buds

Appalachian Azure caterpillar being tended by ants, on Black Cohosh (Actaea racemosa) flower buds

Although I have seen Appalachian Azure caterpillars, I’ve never seen the butterfly. The Appalachian Azure closely resembles the Summer Azure, pictured below.

Summer Azure

Summer Azure

People use Black Cohosh, primarily the root, for medicinal purposes. Black Cohosh contains chemical compounds that are anti-inflammatory, antirheumatic, and that have efficacy in managing female reproductive system problems.  Black Cohosh is approved in Germany for treating menopausal symptoms.  Several indigenous Native American tribes also used Black Cohosh to treat rheumatism and other ailments.

Black Cohosh is native primarily in the eastern United States and the Canadian provinces of Quebec and Ontario. It grows in rich, moist woods, in ravines and on slopes.  Its height can range from just over two feet (.7 meters) to as much as eight feet (2.5 meters).  Black Cohosh will light up a shade garden, blooming from late June through early August.

Black Cohosh (Actaea racemosa, syn. Cimicifuga racemosa)

Black Cohosh (Actaea racemosa, syn. Cimicifuga racemosa)

Who uses Black Cohosh? Insects do, including bees, flies, beetles, ants, and butterflies; spiders and other predators of the insects feeding there do, and even people use it, for medicinal purposes and for the beauty it brings to a garden.

Related Posts

Spring Azures

Resources

Cech, Rick; Tudor, Guy. Butterflies of the East Coast.  2005.

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

Eisner, Thomas. For Love of Insects.  2003.

Evans, Arthur V. Beetles of Eastern North America.  2014.

Foster, Steven; Duke, James A. A Field Guide to Medicinal Plants and Herbs of Eastern and Central North America.  2000.

Hoffmann, David. Medical Herbalism.  2003.

Marshall, Stephen A. Insects Their Natural History and Diversity. 2006.

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

Willmer, Pat. Pollination and Floral Ecology. 2011

USDA NRCS Plant Database