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

 

 

 

Swamp Rose Mallow – for Bees, Butterflies, Beetles, Birds and Beauty

Swamp Rose Mallow (Hibiscus moscheutos)

Swamp Rose Mallow (Hibiscus moscheutos)

The huge, showy blossoms of Swamp Rose Mallow (Hibiscus moscheutos), a member of the Mallow (Malvaceae) family, begin to appear in mid-summer, and continue into early fall.  The flowers are most often pink

Swamp Rose Mallow (Hibiscus moscheutos)

Swamp Rose Mallow (Hibiscus moscheutos)

or white, sometimes with a red throat, inspiring a different common name, Crimsoneyed Rose Mallow.

Swamp Rose Mallow (Hibiscus moscheutos)

Swamp Rose Mallow (Hibiscus moscheutos)

But deeper shades of pink and even red are possible.

Swamp Rose Mallow (Hibiscus moscheutos)

Swamp Rose Mallow (Hibiscus moscheutos)

Eastern Tiger Swallowtail butterfly nectaring at Swamp Rose Mallow (Hibiscus moscheutos)

Eastern Tiger Swallowtail butterfly nectaring at Swamp Rose Mallow (Hibiscus moscheutos)

Insects like the Eastern Tiger Swallowtail in the photo above are enticed to visit Swamp Rose Mallow’s flowers for the nectar accessible through slits at the base of the flower.

In addition to seeking nectar, bees visit to harvest the abundant pollen the flowers offer. Bees eat pollen, and female bees gather it to provision their nests with this nutritious food for their larvae.  The Rose Mallow Bee (Ptilothrix bombiformis) is a specialist forager that only eats the pollen of plants in this genus (Hibiscus) and one other, Morning Glories (Ipomoea).

Bees harvesting pollen from Swamp Rose Mallow (Hibiscus moscheutos). Note the pollen grains all over their bodies.

Bees harvesting pollen from Swamp Rose Mallow (Hibiscus moscheutos). Note the pollen grains all over their bodies.

Numerous stamens (the male reproductive parts) form a tube that encircles the pistils (female reproductive parts). Each stamen is topped by an anther that releases pollen.  At the tips of the pistils are the stigmas, the receptive part of the pistil where the pollen must be deposited in order to initiate pollination.  The stigmas extend significantly beyond the stamens, separating them from the flower’s own pollen, thus decreasing the chances that the flower will be self-pollinated.

Bee harvesting pollen from Swamp Rose Mallow (Hibiscus moscheutos). Note the stigmas to the left of the bee.

Bee harvesting pollen from Swamp Rose Mallow (Hibiscus moscheutos). Note the stigmas to the left of the bee.

Bees are thought to be the primary pollinators of Swamp Rose Mallow, in spite of the fact that they devour vast quantities of its pollen.  It also seems plausible that large butterflies such as the Eastern Tiger Swallowtail are effective pollinators of Swamp Rose Mallow. Butterflies visit the flowers purely for nectar; they have no interest in consuming pollen.  Butterflies head for the nectaries, accessed through slits at the throat of the flower.  As the butterflies drink, their bodies brush against the anthers, picking up pollen.  When the butterfly moves on to a different flower, some of that pollen may adhere to the stigmas of the new flower, triggering pollination.

Eastern Tiger Swallowtail nectaring at Swamp Rose Mallow (Hibiscus moscheutos). The butterfly's wings and body brush against the anthers, picking up pollen.

Eastern Tiger Swallowtail nectaring at Swamp Rose Mallow (Hibiscus moscheutos). The butterfly’s wings and body brush against the anthers, picking up pollen.

Eastern Tiger Swallowtail nectaring at Swamp Rose Mallow (Hibiscus moscheutos). The butterfly's wings and body brush against the flower's stigmas, depositing pollen, then against the anthers, picking up pollen.

Eastern Tiger Swallowtail nectaring at Swamp Rose Mallow (Hibiscus moscheutos). The butterfly’s wings and body brush against the flower’s stigmas, depositing pollen, then against the anthers, picking up pollen.

There isn’t much waste in nature.  Bees even scavenge pollen that has fallen onto the flower petals.  Beetles join the bees at this pollen feast.  Hibiscus Seed Beetles (Althaeus hibisci) are primarily interested in eating the seeds of Swamp Rose Mallow and other related species, but while they wait for the seeds to become available, they also consume pollen.  As an additional benefit, cruising the flowers is an effective way for the beetles to hook up with members of the opposite sex!

Bee and Hibiscus Seed Beetles (Althaeus hibisci) scavenging for pollen that has fallen onto the petals of a Swamp Rose Mallow (Hibiscus moscheutos) flower.

Bee and Hibiscus Seed Beetles (Althaeus hibisci) scavenging for pollen that has fallen onto the petals of a Swamp Rose Mallow (Hibiscus moscheutos) flower.

Hibiscus Seed Beetles (Althaeus hibisci)

Hibiscus Seed Beetles (Althaeus hibisci)

Swamp Rose Mallow benefits butterflies in other ways.  It is a potential food plant for the caterpillars of several butterflies, including the Gray Hairstreak, Common Checkered-skipper, and Painted Lady.

Gray Hairstreak on goldenrod. The caterpillars of the Gray Hairstreak butterfly eat the foliage of members of the Mallow (Malvaceae) and Pea (Fabaceae) families, as well as some other plants.

Gray Hairstreak on goldenrod. The caterpillars of the Gray Hairstreak butterfly eat the foliage of members of the Mallow (Malvaceae) and Pea (Fabaceae) families, as well as some other plants.

Common Checkered-skipper on aster. The caterpillars of the Common Checkered-skipper butterfly have evolved to eat plants from the Mallow (Malvaceae) family.

Common Checkered-skipper on aster. The caterpillars of the Common Checkered-skipper butterfly have evolved to eat plants from the Mallow (Malvaceae) family.

Painted Lady on Purple Coneflower (Echinacea purpurea). The Painted Lady is the most widespread butterfly in the world. It is a generalist, with its caterpillars able to eat plants from the Mallow (Malvaceae) and Pea (Fabaceae) families, along with thistles, sunflowers and many other plants.

Painted Lady on Purple Coneflower (Echinacea purpurea). The Painted Lady is the most widespread butterfly in the world. It is a generalist, with its caterpillars able to eat plants from the Mallow (Malvaceae) and Pea (Fabaceae) families, along with thistles, sunflowers and many other plants.

Birds also benefit from the presence of Swamp Rose Mallow. Red-winged Blackbirds may use it as a nesting site.

Male Red-winged Blackbird

Male Red-winged Blackbird

Swamp Rose Mallow’s seeds are a fall and winter source of food for birds,

Swamp Rose Mallow (Hibiscus moscheutos) fruit capsules open to release their seeds.

Swamp Rose Mallow (Hibiscus moscheutos) fruit capsules open to release their seeds.

including Northern Pintails, Wood Ducks and Blue-winged Teal.

Northern Pintails with Swamp Rose Mallow (Hibiscus moscheutos) in winter

Northern Pintails with Swamp Rose Mallow (Hibiscus moscheutos) in winter

Wood Duck pair in non-breeding plumage. (Female left, male right.)

Wood Duck pair in non-breeding plumage. (Female left, male right.)

Blue-winged Teals

Blue-winged Teals

Swamp Rose Mallow is native from Ontario, New York and Massachusetts in the north, south to the southeastern and south central United States. It can grow to a height of about 6.5 feet (2 meters).  Swamp Rose Mallow’s natural habitats are primarily wetlands, including swamps, marshes

Swamp Rose Mallow (Hibiscus moscheutos) at the Abbott Marshlands, Hamilton Township, Mercer County, New Jersey

Swamp Rose Mallow (Hibiscus moscheutos) at the Abbott Marshlands, Hamilton Township, Mercer County, New Jersey

and wet meadows.

Swamp Rose Mallow (Hibiscus moscheutos) in the meadow at Bowman's Hill Wildflower Preserve, New Hope, PA

Swamp Rose Mallow (Hibiscus moscheutos) in the meadow at Bowman’s Hill Wildflower Preserve, New Hope, PA

Resources

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

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

Willmer, Pat. Pollination and Floral Ecology. 2011

Illinois Wildflowers

Shimamura, Ryouji; Kachi, Naoki; Kudoh, Hiroshi; Whigham, Dennis F. Visitation of a specialist pollen feeder Althaeus hibisci Olivier (Coleoptera: Bruchidae) to flowers of Hibiscus moscheutos L. (Malvaceae). 2004.

USDA NRCS Plant Database

U.S. Forest Service Database

Klips, Robert A.; Sweeney, Patricia M.; Bauman, Elisabeth K. F.; Snow, Allison A. Temporal and Geographic Variation in Predispersal Seed Predation on Hibiscus moscheutos L. (Malvaceae) in Ohio and Maryland, USA. 2005.

 

 

White Beardtongue for Pollinators

White or Foxglove Beardtongue (Penstemon digitalis) blooms in late spring to early summer, offering nectar and pollen to flower visitors.  It’s easy to recognize in fields and along roadsides by its upright habit and its inflorescence of many whitish flowers, all positioned perpendicularly to the stem.  The name Penstemon reflects the fact that these flowers each have five male flower parts, called stamens.  ‘Foxglove’ and ‘digitalis’ both refer to the shape of the flowers, which resemble those of Foxglove (Digitalis purpurea).

White or Foxglove Beardtongue (Penstemon digitalis)

White or Foxglove Beardtongue (Penstemon digitalis)

The white flowers beckon to a variety of bees who are enticed by the possibility of a meal of nectar and pollen, with the purple lines (nectar guides) on the throat of the flower showing them the way.

Bufflehead Mason Bee (Osmia bucephala) on White Beardtongue (Penstemon digitalis)

Bufflehead Mason Bee (Osmia bucephala) on White Beardtongue (Penstemon digitalis)

Sweat Bee on White Beardtongue (Penstemon digitalis)

Sweat Bee on White Beardtongue (Penstemon digitalis)

Bee on White Beardtongue (Penstemon digitalis)

Bee on White Beardtongue (Penstemon digitalis)

In addition to feeding themselves, female bees also harvest pollen and nectar to provision their nests for their larvae. But if bees are eating and harvesting the pollen, how will the flowers be pollinated?  Will there be any pollen left to fulfill the plant’s goal of reproduction?

Female Bumble Bee on White Beardtongue (Penstemon digitalis). Note the harvested food on her hind leg.

Female Bumble Bee on White Beardtongue (Penstemon digitalis). Note the harvested food on her hind leg.

Although much of its pollen is used to entice and reward insect visitors, White Beardtongue’s strategy is to deposit pollen on its flower visitors’ bodies in a place that can’t be easily reached for grooming.

The flowers have both male and female parts, but they are sequentially unisexual. The male flower parts, or stamens, mature first, with the anthers at their tips opening up to release pollen. Although White Beardtongue has five stamens, only four are capable of producing fertile pollen. These four stamens are all positioned just below the ‘roof’ of the flower tube, or corolla.  The dark brown anthers, which contain the pollen, are at the tips of the stamens, clustering above the center of the entrance to the flower.

White Beardtongue (Penstemon digitalis) in the male phase. The dark brown anthers are clustered just below the center of the ‘roof’ of the flower.

White Beardtongue (Penstemon digitalis) in the male phase. The dark brown anthers are clustered just below the center of the ‘roof’ of the flower.

When the flowers are in this phase, a visitor like the Bumble Bee in the photo below may enter the flower, and be brushed with pollen on the top of its head, thorax or even its tongue (proboscis).

Bumble Bee on White Beardtongue (Penstemon digitalis).

Bumble Bee on White Beardtongue (Penstemon digitalis).

After a day or so, the anthers begin to wither and the female flower part begins to mature, the sticky stigma at its tip becoming receptive to pollen. The style extends and curves downward, taking the same position that the anthers once held.

White Beardtongue (Penstemon digitalis) in the female phase. The stigma has replaced the anthers just below the center of the ‘roof’ of the flower.

White Beardtongue (Penstemon digitalis) in the female phase. The stigma has replaced the anthers just below the center of the ‘roof’ of the flower.

If a bee carries the pollen to a flower in the female phase, it will generally enter the flower in the same way, depositing the pollen on the receptive stigma. Success!  White Beardtongue’s pollination strategy has worked.

Bumble Bee depositing pollen on stigma of a White Beardtongue (Penstemon digitalis) in the female phase.

Bumble Bee depositing pollen on stigma of a White Beardtongue (Penstemon digitalis) in the female phase.

Some pollen may fall on the ‘floor’ of the flower, where the fifth stamen is positioned. This stamen is sterile; it does not produce its own pollen.  It is somewhat hairy, giving the plant its common name ‘beardtongue’.  This hairy stamen may catch some of the fallen pollen and deposit it on an insect visitor as it brushes past, a secondary means of pollen dispersal.  Some smaller bees may cling upside down while foraging for pollen.

Bee visiting White Beardtongue (Penstemon digitalis), possibly harvesting pollen

Bee visiting White Beardtongue (Penstemon digitalis), possibly harvesting pollen

Butterflies and even hummingbirds may stop by for nectar. They may not be as effective in pollinating White Beardtongue as the bees are if their anatomy and behavior is not as good a match for the anatomy of the flower.  On the plus side, neither butterflies nor hummingbirds harvest pollen, so any that does adhere to them has the possibility of being deposited on another flower.

Hobomok Skipper butterfly visiting White Beardtongue (Penstemon digitalis) for nectar. It may be just the right size to pick up or deliver pollen on its head.

Hobomok Skipper butterfly visiting White Beardtongue (Penstemon digitalis) for nectar. It may be just the right size to pick up or deliver pollen on its head.

White Beardtongue blooms for a period of about a month in June to early July. It is native in the eastern two-thirds of the United States, and is found in several Canadian provinces.  It can tolerate sun to part shade in dry to somewhat moist, well-drained soil, and grows to a height of 2-5 feet (6 – 15 decimeters).  It’s a good addition to a natural area or a pollinator garden.

Bumble Bee visiting White Beardtongue (Penstemon digitalis)

Bumble Bee visiting White Beardtongue (Penstemon digitalis)

Here are some other early summer blooming plants that are important for pollinators:

Milkweed – It’s Not Just for Monarchs

What Good is Dogbane?

Resources

Eastman, John. The Book of Field and Roadside.  2003.

Holm, Heather. Pollinators of Native Plants.  2014.

Willmer, Pat. Pollination and Floral Ecology. 2011

Illinois Wildflowers

Lady Bird Johnson Wildflower Center Plant Database

Ontario Wildflowers

USDA NRCS Plant Database

 

 

 

Black Cherry – for Wildlife, and People, too!

Black Cherry or Wild Black Cherry (Prunus serotina) is a bountiful tree for wildlife, and an important species for humans, too.  It blooms in spring, with a profusion of long, slender, densely packed flower clusters.

Black Cherry (Prunus serotina) in bloom

Black Cherry (Prunus serotina) in bloom

The flowers offer nectar and pollen as enticements to a variety of bee and fly species who need this food to survive. The insects become Black Cherry’s unsuspecting pollination partners.  In return for the food provided to these insect floral visitors, the flowers benefit by having some of their pollen transported on the insects’ bodies and deposited advantageously for pollination on other Black Cherry flowers.  Successful pollination will result in fruit that ripens in late summer and fall.

A broad spectrum of animals eat Black Cherry’s fleshy fruit. Many thrushes, woodpeckers, sparrows, bluebirds, tanagers, orioles, and Cedar Waxings are among the dozens of bird species that eat the fruit.

Wood Thrush

Wood Thrush

Red-bellied Woodpecker

Red-bellied Woodpecker

Mammals as diverse as fox, squirrels, chipmunks, mice and even Black Bears eat Black Cherry’s fruit.

Eastern Chipmunk

Eastern Chipmunk

The fruit has evolved to lure animals to help Black Cherry spread its seeds. In exchange for the meal, the seeds are ‘dispersed’ after traveling through the animals’ digestive tracts.

Hundreds of insect species depend on Black Cherry for food, and in some cases, shelter.

In spring, finger galls caused by a mite (Eriophyes cerasicrumena) are conspicuous on Black Cherry leaves.  A gall is a plant’s reaction to being used as food and shelter by an insect.  The mite will feed on the tissue inside the gall until the mite matures and emerges from the gall.

Finger galls caused by a mite (Eriophyes cerasicrumena) on Black Cherry (Prunus serotina) leaves

Finger galls caused by a mite (Eriophyes cerasicrumena) on Black Cherry (Prunus serotina) leaves

You may be used to seeing Eastern Tiger Swallowtail butterflies feeding on nectar from a variety of plants.

Eastern Tiger Swallowtail nectaring at Wild Bergamot (Monarda fistulosa) flowers

Eastern Tiger Swallowtail nectaring at Wild Bergamot (Monarda fistulosa) flowers

But Eastern Tiger Swallowtail caterpillars have a completely different diet. They depend on the leaves of several woody plants species as their food source, including Black Cherry.

Eastern Tiger Swallowtail caterpillar in Black Cherry leaf

Eastern Tiger Swallowtail caterpillar in Black Cherry leaf

Eastern Tiger Swallowtails are just one of 456 species of butterflies and moths whose caterpillars eat the leaves of Black Cherry and other Prunus species, according to research from Douglas W. Tallamy and the University of Delaware.  These caterpillars are in turn an important source of food for birds, especially when they are raising their young.

Tufted Titmouse - one of many bird species that harvest caterpillars from Black Cherry

Tufted Titmouse – one of many bird species that harvest caterpillars from Black Cherry

Tent caterpillars favor Black Cherry, a practice that gardeners usually view unfavorably.

Tent Caterpillar egg mass in winter

Tent Caterpillar egg mass in winter

But even Tent caterpillars have redeeming qualities, since they are an important food source for both Yellow- and Black-billed Cuckoos.

Yellow-billed Cuckoo

Yellow-billed Cuckoo

Adult butterflies and moths may also become food for birds or other insects, and in the case of night-flying moths (including Tent caterpillars that survive to become adult moths), for bats.

In addition to the nectar offered by its flowers, Black Cherry provides nectar from glands on its leaf stems. These nectaries are not targeting pollinators.  Instead, they are there to lure a mercenary army of ants to protect the tree from herbivores, especially caterpillars. The nectaries entice ants to visit the trees for a drink.  While there, the ants may also help to keep the caterpillar population in check, since ants also need insect protein as part of their diet.

Black Cherry (Prunus serotina) in bloom

Black Cherry (Prunus serotina) in bloom

People benefit directly from Black Cherry trees.  In addition to the beauty of its flowers, fruits and foliage, Black Cherry’s wood is an important timber crop, primarily for use in furniture and cabinet making.  Black Cherry’s fruit is used to flavor brandies and to make a liqueur called cherry bounce.  The fruit is somewhat bitter, but with added sugar it can be used to make jellies.  Eating the raw fruit is not advisable, since the seeds can be toxic.  Medicinally, Black Cherry’s inner bark has been used in cough suppressants.

Black Cherry can grow to a maximum height of 80-100 feet (24-30 meters). Its range is primarily eastern North America, from Canada through the United States and south into Mexico, although it is an adaptable species and may also be found in some areas of the Pacific Northwest.

Providing beauty, timber, food and medicine for humans, food for birds, mammals, pollinators and hundreds of other insects, Black Cherry is among our most productive native trees.

Black Cherry (Prunus serotina) in bloom

Black Cherry (Prunus serotina) in bloom

Related Posts

Will Work for Food – Extrafloral Nectaries

Resources

Eastman, John. The Book of Forest and Thicket.  1992.

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.

Hoffmann, David. Medical Herbalism.  2003.

Peterson, Lee Allen. A Field Guide to Edible Wild Plants of Eastern and Central North America. 1977.

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

Tallamy, Douglas W. Bringing Nature Home, 2007,

Illinois Wildflowers

USDA Plant Database

 

Spring Azures

Spring Azures spent the winter as pupa, cozy in their chrysalises, poised to take the final step to adulthood when spring conditions were right, with longer days and warmer temperatures. Their fluttering flight showing flashes of azure began lighting up woodlands and gardens earlier than usual this year, when unseasonably warm March temperatures encouraged them to complete their metamorphosis and emerge as early as the last week of March.

Spring Azure butterfly

Spring Azure butterfly

Nectar was scarce in those early days of emergence, especially when weather whiplash sent the temperatures in the opposite direction, dropping below normal. During the lean times, Spring Azures got their nourishment from a variety of mineral sources, including mud puddles, rocks, leaves, and even bird droppings.

Spring Azure getting nutrients from bird droppings

Spring Azure getting nutrients from bird droppings

As temperatures soared again, nectar supplies became plentiful.

Spring Azure dringing nectar from Wild Plum (Prunus americanus) blossoms

Spring Azure dringing nectar from Wild Plum (Prunus americanus) blossoms

Now their priority is reproduction – making sure their species has a future. After mating, female Spring Azures look for plants appropriate for egg-laying, plants whose leaves their caterpillars can eat and on which they will thrive.  Spring Azures evolved to use the newly emerging leaves, flowers and buds of a variety of woody plants as their caterpillars’ food, including viburnums, dogwoods (Cornus species), and New Jersey Tea (Ceanothus americanus). For the past week, I’ve watched Spring Azures flitting from plant to plant, and from leaf to bud of Maple-leaf Viburnum (Viburnum acerifolium), taking only seconds to lay each egg.

Spring Azure laying an egg on Maple-leaf Viburnum (Viburnum acerifolium) flower buds

Spring Azure laying an egg on Maple-leaf Viburnum (Viburnum acerifolium) flower buds

The eggs will hatch and caterpillars will emerge, nibbling on the newly developing leaves and buds. Not all of the caterpillars will complete metamorphosis to fly as butterflies, however.  Caterpillars are very vulnerable to predators, including other insects, spiders and birds.  Caterpillars are an essential source of food for birds, especially when they are feeding their young.  It may take thousands of caterpillars to feed a hungry clutch of growing birds.

Hungry young Tufted Titmouse looking for food

Hungry young Tufted Titmouse looking for food

Normally, ants would be among the insects that would love to eat a tasty caterpillar treat. Even when fully grown Azure caterpillars are small, the perfect snack size for an industrious ant on the hunt.  To protect themselves, Azure butterflies have developed a way to enlist the ants to protect them rather than eat them.  Azures produce delicious honeydew that ants love.  The ants guard the Azure caterpillars, palpating them to trigger the honeydew payment.

Ant guarding/palpating an Azure caterpillar for honeydew. They're on New Jersey Tea (Ceanothus americanus).

Ant guarding/palpating an Azure caterpillar for honeydew. They’re on New Jersey Tea (Ceanothus americanus).

Ants will work for the highest bidder, and in this case they help some of those caterpillars live to become butterflies.

Spring Azure butterfly on Maple-leaf Viburnum (Viburnum acerifolium)

Spring Azure butterfly on Maple-leaf Viburnum (Viburnum acerifolium)

 

Related Posts

‘Will Work for Food’ – Extra-floral Nectaries

Maple-leaf Viburnum

Gray Dogwood for Butterlies, Bees and Birds

Resources

Butterflies and Moths of North America

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