Horse Nettle: Flowers, Prickles, Fruit, Toxicity

When I walk through the open areas of Eliza Howell Park these summer days, I often focus on flowering plants. One that is currently blooming is Horse Nettle.

Horse Nettle in the park is usually only about two feet high and not very conspicuous. A closer look clearly reveals the 5 petals (white to sometimes pale purple) with yellow anthers.

Originally found in southeast North America, Horse Nettle has spread north, being in Michigan since about 1890. It is is often found in fields and pastures, and spreads by both seeds and rhizomes.

It has often gotten attention — and been considered a “weed” — because it is poisonous to grazing animals and it retains its toxicity in dried hay used as winter feed. Mammals tend to avoid eating it when other food is available, however, in part because of the prickly spines found on the stems.

It was the fruit that first led me to want to know this species better. The berries ripen from green to yellow and look somewhat like small yellow tomatoes.

This photo is from October.

The berries later lose much of their firmness but hang on the stems into the winter.

All parts of Horse Nettle are toxic. It contains solanine, which affects the digestive system. Grazing mammmals (like horses) are at risk of eating the leaves and humans are more at risk of eating the berries. The most serious consequences result from more than minimal consumption.

As is often the case with plants that have an effect on human functioning, Horse Nettle has historically sometimes been used medicinally.

Many of the wildflowers in Eliza Howell become more fascinating as I get to know them better. Horse Nettle is one.

Wild Bergamot in Bloom: Attracting Butterflies and Bumblebees

One of my favorite Eliza Howell Park wildflowers is now in bloom — Wild Bergamot. It is very easy to find patches of these three-feet tall plants sporting multitudinous lavender blossoms.

Wild Bergamot, a plant of the mint family that is sometimes called Bee Balm, is a favorite of mine in large part because it is a magnet for fascinating insects, especially pollinators. I frequently stop at one of these patches, knowing that there is an excellent chance of seeing butterflies and an assurance of seeing other insects.

Butterflies that I have been seeing the last four days, camera in hand, include:

Great Spangled Frittilary

Eastern Tiger Swallowtail

Silver-spotted Skipper

Black Swallowtail

Wild Bergamot blooms for about a month, attracting an increasing variety of insects as the month progresses. At present, the most numerous visitors are bumblebees, present in great number.

Bumblebees crawl over the flowers, gathering pollen.

There are many different kinds of bumblebees (19 have been recorded in Michigan) and I am not able to identify them by individual species.

Bumblebees are among the largest of bees and, like honeybees, live together as a social unit. But unlike honeybees, which were introduced from Europe shortly after Europeans came to North America, bumblebees are native here.They appear to be the primary pollinator of many wildflowers in Eliza Howell Park.

Though bumblebees may look scary, they are so focused on pollen that they can be approached very closely without danger as they work the flowers.

The flowering of Wild Bergamot signals that the wildflower and butterfly season is definitely underway. The next few weeks is the time to experience the wealth of wildflowers and to admire all the insects they attract.

The Detroit Audubon Wildflower and Butterfly field trip to Eliza Howell Park is scheduled for July 31 this year.

Joe Pye Weed, Purple Coneflower, Ironweed, and a variety of other flowers will be getting attention very soon, but Wild Bergamot deserves the focus these early days of July.

Red Milkweed Beetle: A Total Milkweed Life Cycle

When the Common Milkweed begins to bloom — which is usually near the end of June in Detroit’s Eliza Howell Park — it is the time to start seeing Red Milkweed Beetles. Their whole life revolves around Milkweed plants.

There are many Common Milkweed plants in the park, often in patches, and it is easy to spot Red Milkweed Beetles on a walk through any of the patches this week.They feed on all parts of the plant — leaves, buds, stems.

Red Milkweed Beetles are in the longhorned beetles family, named for the length of the antennae. The antennae are right by the eyes, giving the head a very interesting appearance.

The adult beetles have recently emerged from the soil and will spend much of the summer eating. They do not congregate in large numbers on any one plant (flying from one milkweed to another) with the result that they do little damage to the plant.

In eating milkweed, they accumulate alkaloid toxins in their bodies, just as Monarch butterflies and some other milkweed insects do, making them nearly immune to predators. And, like the other insects that have this milkweed advantage, they advertise their toxicity by their red/orange color.

They don’t need to hide or use camouflage for protection.

This is the season for eating, and it is also the season for mating. Females lay their eggs on milkweed stems by the ground. When hatched, the larvae bore into the stems or dig into the ground and work their way to the roots, where they spend the winter. The adults die in the fall.

It appears this female is not interrupting her eating while mating.

Red Milkweed Beetles are completely dependent upon milkweed plants. Put differently, they specialize in milkweeds. They are common where milkweeds are common and not anywhere else.

I find it fascinating to observe and learn about the life cycles of different insects. This week Red Milkweed Beetle has been the focus of much of my attention.

Tawny Emperor and Hickory Hairstreak: A Good Butterfly Day

Now that Summer is here, butterflies are seen more frequently. Especially on sunny days, I am alert to flittering flights while walking in Eliza Howell Park, eager to see which species are active.

June 24 was sunny and a very good butterfly day.

Perhaps the best find of the day was this Tawny Emperor.

Southern Michigan is the northern edge of the Tawny Emperor’s geographical range, so they are not common here. I see one only occasionally.

Their color varies and I find this one, a little darker than many, very attractive. It was in the meadow, near the walking path.

The next unusual find was on the footbridge, resting on the metal railing. It is a Hickory Hairstreak.

Lepidopterists sometimes note that Hickory Hairstreak is “rarely seen.” This is only the second time I have found it in Eliza Howell and, since there are other Hairstreaks that are similar (especially Banded Hairstreak), I have consulted experts both times to confirm identification.

These two were the most most unusual sightings of the day, but others are also notable.

The Mourning Cloak, with its fascinating life cycle, is always good to see.

Rhe Mourning Cloak is not often photographed in this position; normally it is pictured from behind. So it might not be immediately recognizable.

Mourning Cloaks spend the Winter in hibernation as adults and emerge on the first warm days of the Spring, often being the first butterfly that I see. This year I saw the first one on March 27.

They lay eggs in the spring and this one has probably just energed from the chrysalis. It has a very long lifetime for a butterfly, 10 or 11months.

After feeding for a couple weeks in June-July, they estivate for the heart of the summer (in a state of torpor or dormancy), before being active again until winter hibernation. If it avoids predators and other threats, this same butterfly might brighten one of my Spring walks next year.

I also encountered a European Skipper feeding on Red Clover.

This is a much less dramatic find, but it is always satisfying to me when I recognize a particular Skipper among the many varieties that look so much alike. And any butterfly nectaring on Red Clover gets my attention.

This good butterfly day was also a good moth day. I saw and was able to get pictures of two colorful daytime flying moths.

One is Virginia Ctenucha.

The orange on the head is barely visible from this angle, but the metallic blue body is clear. As can be seen, this a nectaring moth. Though it is diurnal, I very rarely see it.

The other moth that presented itself was in the woodland, in a patch of nettles (the leaves stung my hands as I worked to get close enough for a picture).

It is called Leconte’s Haploa Moth.

The Leconte’s Haploa is about an inch long with a two inch wingspan. It is best known for its appearance. When the wings are held like this, it has reminded some of a crusaders shield.

There are some days when my nature walk leads to additional hours afterwards spent reviewing what I observed in the field. June 24 was one of these special days.

Swamp Milkweed: The Third Milkweed Species

Milkweeds are just beginning to bloom in Eliza Howell Park in the third and fourth weeks of June. I find myself paying special attention this year to Swamp Milkweed, a species that I have not written about before.

In fuller bloom, Swamp Milkweed looks like this.

Previous milkweed-related posts have focused on Common Milkweed and Butterfly Weed, both more widespread in the park. Based upon my most recent observations, Swamp Milkweed is, however, a little more common than I had thought.

In this collage, Butterfly Weed is on the top left, Common Milkweed is bottom left, and Swamp Milkweed is on the right.

As its name indicates, Swamp Milkweed grows best in wetter areas. As writers sometimes say, it likes to grow where “it can get its feet wet.”

The best area for finding it in Eliza Howell is in the wet meadow, near what I refer to as the toad breeding pond. Here is a small patch, not yet in bloom, that I have been watching.

All three of these milkweed species are host species for Monarch Butterfly larvae. And Swamp Milkweed, like Common Milkweed, has the white sticky sap that is the basis for the family name. (Butterfly Weed is the family exception in that it does not have this “milk.”)

While Swamp Milkweed is selective in its growing environment, it is geographically widespread. (This map is from the USDA.)

Perhaps because it grows primarily in a different part of park from the major summer wildflower displays, it doesn’t usually get visited as frequently as the other two milkweed species. This year I am definitely enjoying getting to know it better.

The leaves are narrower than those of the Common Milkweed, but larger than Butterfly Weed leaves.

There are other milkweed species that grow in Michigan, but to date I am aware with only three in Eliza Howell Park. As I am always learning more about park flora and fauna, perhaps one of these days I will discover a fourth local species!

Prickly Pear: A Cactus Grows in Detroit

On May 12, while looking at some Lupines in Eliza Howell Park, I noticed a plant that I had never expected to see here: a Prickly Pear cactus.

It was small, a single pad only 3 – 4 inches high, growing in the wildflower field fairly close to two large oak trees.

While Eastern Prickly Pear is native to locations in the Northeast and the Midwest, including some areas in Michigan, it is not known to grow in the wild in the Detroit area.

When I mentioned the find to others, one of the first questions was how did it get here. Since it is able to tolerate cold winters, it is sometimes grown as a garden plant. It is possible that it came from a garden, either as a deliberate transplant or as a seed that got deposited in this location.

There was no evidence that it had been planted recently, no disturbed ground. It appears to have spent the winter in this location.

I am more interested in finding the answer to a different question: will it survive and thrive here. So I made note of its exact location (single small plants are often hard to relocate) and now stop by regularly.

By the end of May, two things were noticeable: 1) a small section had been broken or bitten off and 2) new growth was evident on two spots on the rim of the pad.

From this view, one growth is in the center by the top and the other is to the left, a little below the top. The one on the left is the faster growing one. Here is a close-up look from May 31.

Prickly Pear pads produce flowers (and fruit) and also grow new pads. Since these new growths first appeared, the one on the side has been growing faster.

On June 4, it looked Iike this.

Since I have never previously had the opportunity to watch a Prickly Pear grow,, I am finding it fascinating to see how and how quickly a single pad develops.

The next two pictures are from June 16, one of the whole plant and one of the emerging new pad on the left side.

However this lone Prickly Pear came to be in Eliza Howell Park, it is now here and it is growing. It will be very interesting to see how well this lone cactus does in this setting. I will be watching.

Little Wood-Satyr: A Common Early June Butterfly

The butterfly seen most frequently in Eliza Howell Park in early June, visible even on cloudy days when other butterflies are not very active, is the Little Wood-Satyr.

As I walk in the wildflower meadow near the edge of trees, I cannot miss them as they fly close to the path, often coming to rest on or near the ground.

When the wings are spread, the six circled black spots (eyespots) help to identify this species. When not flying, Little Wood-Satyr shows itself both with wings spread (as above) and with wings closed.

When the wings are closed, the two lines on the underwing are quite visible.

The wingspan is a little over 1 and 1/2 inches. Its flight, sometimes described as “bouncy” or as “dancing,” contributes to it being so noticeable. It feeds on grasses and other plants and is not a species that is attracted to the nectar of flowers.

There is only one brood a year (they overwinter as caterpillars) and the adults will be gone when summer reaches its peak and this meadow is filled with prairie flowers attended to by a variety of other butterflies.

Little Wood-Satyr is found throughout the Eastern part of the United States. (This map is from Garden with Wings.)

When summer truly arrives, this area near the edge of the woods will be populated by another type of satyr, the Common Wood-Nymph.

Wood-Nymphs are larger (wingspan over 2 inches) and are a nectaring species. They do not spread their wings when nectaring and are distinguished by 2 yellow-ringed black eyespots on the forewing.

From July through September, this prairie flower area in Eliza Howell will be visited by many admirers of wildflowers and of butterflies. Now, when very few of the flowers are blooming, there are not many of us walking among the plants.

We who are here now have a great opportunity to get to know the Little Wood-Satyr. And come to recognize that even little brown “bugs” can be lovely and fascinating.

May Yellow Wildflowers

A month ago, at the end of April, most of the early blooming wildflowers in Eliza Howell Park were in the woodlands. As May progressed, more flowers began to appear in the fields and meadows.

Once again this year I have been struck by how many of these early meadow species have yellow flowers.

Golden Ragwort

Small patches of Golden Ragwort are scattered in the park. They are less than 2 feet tall and, growing among other meadow plants, can be missed from a distance. When my walks bring me close, the clusters of small blooms always lead me to stop and admire.

Yellow Wood-Sorrel

Yellow Wood-Sorrel is a small wildflower that is very common in this part of the country (gardeners often see them). Each tiny 5-petaled flower is 1/2 inch across at most. They’re distinguished from other small 5-petaled yellow flowers (like Cinquefoil) by the leaves that resemble 3-leaf clovers.

Cinquefoil

There are different Cinquefoil species with yellfow flowers. This one (Common Cinquefoil, I think) grows along the ground and sends up individual flowers, which are about 1/2 inch across. Each petal is slightly notched.

Yellow Goat’s Beard

Yellow Goat’s Beard is a taller flower, reaching above the rapidly growing grasses in single flowers, nearly 2 inches across and resembling tall Dandelions.

The color yellow has often been recognized as symbolizing sunshine. Goat’s Beard and Dandelion are two wildflowers that might suggest sun.

Dandelion

Dandelion needs no description and is usually considered a weed (a weed being in many cases a flower growing where it is unwanted).The scattered bright yellow Dandelions in Eliza Howell Park add to the overall scene of attractive yellow May wildflowers.

Coreopsis

Just now, as May is nearing the end, Coreopsis is beginning to bloom. It is the first of the larger meadow and prairie wildflowers that will populate the park in the months to come.

Coreopsis flowers appear singly on the tips of the stems. Each has 8 petals with each petal having several lobes at the tip.

….

There have been a few wildflowers blooming in May that are not yellow, but yellow has definitely been the dominant color.

The color yellow is often said to symbolize happiness and optimism (in addition to sunshine). It fitting, perhaps, that yellow is the dominant flower color in May, a month of rising spirits for many.

Tiny Praying Mantises Emerge – after 8 Months

Last September, my colleague Kevin Murphy and I spent hours finding and watching dozens of Chinese Praying Mantises in the fields of Eliza Howell Park. They were nearing the end of their season — and their lives — and their last couple of weeks include mating and egg laying. The only survivors for the following year are the eggs encased and attached to plants judged sturdy enough to remain standing through the winter.

Since September, we have checked occasionally on a number of these egg cases (oothecae) and were pleased to see that they appeared to remain intact.

During the Fall and Winter and early Spring, the eggs hatch and the young grow inside the egg cases into very small versions of the adult, but without wings. We have been waiting to see them emerge, not knowing exactly when this would happen or whether we would actually be able to observe it, since they disperse quickly.

On May 17, Kevin spotted one hanging from an egg case.

We expected to see them energe in large numbers, not one at a time. Was this one the first to emerge from the case or the one remaining after all the others had hurried away to get started on their unencased lives?

On May 21, I came by at the right time and found an egg case open with many departing mantises. As I watched, they quickly climbed to a branch to get away. (Emerging mantises are hungry and have been known to eat other egg case graduates.)

Eight months is a long time inside, when the total time from egg being laid to death is only 12 months.

Over the summer, the mantises will slowly grow until they reach full adult size. Then, in September, they will seek others out to prepare for another year, another generation.

We will be there, to observe the cycle continue and to try to gain additional knowledge and understanding of these fascinating insects.

Ruby-throated Hummingbird: Male Territoriality

I saw the first Ruby-throated Hummingbird of the spring in Eliza Howell Park on May 4 this year.

As usual, the first one seen was a male; males return to their breeding ground earlier than females.

And as usual, I saw it perched on a bare branch of a fairly small dead tree. Males quickly claim a territory and watch over it carefully.

Photo by Margaret Weber

Over the last 10 years or so, I have come to expect to see a male Ruby-throated Hummingbird perched in the same tree on a daily basis. He is not there every time I walk past, but more often than not.

(Individual hummingbirds do not normally live 10 years, so I think this is at least the second generation claiming this spot.)

When the hummingbird in the tree is pointed out on nature walks, visitors often express surprise at seeing one perched. They are used to seeing a hovering bird, at flowers or at a feeder, not one watching zealously over its territory from a favorite perch.

Photo by Margaret Weber

The male’s role is pretty much defined by its territoriality. Ruby-throated Hummingbirds do not form breeding pairs. When a female enters the territory, the male performs a courtship display. If the female is interested, they mate.

And that is the end of the male’s role in parenting. The female makes the nest on her own, does all the incubating, feeds the young by herself.

The male watches over his territory.

Photo by Margaret Weber

While there is one tree that seems to be used most frequently, the male also perches on other open branches as it performs its sentry duty. It quickly darts from one to another.

Photo by Margaret Weber

The number of perching sites that I have been seeing during the past week and the distance between one end of the route and the other suggest that there are now likely two adjacent territories patrolled by two different males. I’m not yet sure.

Occasionally stopping to nectar at a flowering tree, the male quickly returns to sentry duty.

Photo by Margaret Weber

Female hummingbirds have just returned. Soon they will begin nesting. Females defend their own nesting territory, if needed, but for the most part they prefer not to be seen.The males, on the other hand, will continue to perch out in the open for about the next 4 months.

Many bird species are territorial. The male Ruby-throated Hummingbird seems to specialize in it.