Category Archives: Plants

A Trumpet For Hummingbirds

Trumpet creeper with an insect inside (photo by Kate St. John)
Trumpet creeper with an insect inside (photo by Kate St. John)

Though we haven't had many hummingbirds this year, Pittsburgh's trumpet creeper is waiting to attract them.

Trumpet vine or trumpet creeper (Campsis radicans) is a woody vine native to eastern North America.  It's so well adapted to the forest edge that it aggressively climbs up to 35 feet to reach the sun.

Its beauty and scent are attractive to gardeners but it requires ruthless pruning.  The Lady Bird Johnson Wildflower Center says, "To keep it in check, plant it near concrete or an area that you can mow; mowing down the suckers will discourage them."

The flower is specially shaped for pollination by ruby-throated hummingbirds, the only hummingbird in this plant's native range.  The tubes are large and the anthers held high. The insect above is too small to pollinate it.

Learn more in this video by the Capital Naturalist.

 

As a trumpet for hummingbirds, it's probably so fragrant because ruby-throats like its scent.  Remember: we learned this month that birds can smell.

 

(photo by Kate St. John; video by The Capital Naturalist on YouTube)

It’s Probably Mugwort

Mugwort leaves are white underneath (photo by Kate St. John)
Mugwort leaves are white underneath, June 2017 (photo by Kate St. John)

There's a tall plant in the Composite family (Asteraceae) that used to confuse me, especially in early summer. Here's a trick for identifying mugwort.  It's everywhere right now.

Mugwort or common wormwood (Artemisia vulgaris) is an aromatic perennial native to Europe, Asia, northern Africa and Alaska(!).  It may have been brought here for medicinal purposes, but it spreads easily along roadsides and waste places.  I'm surprised it's not on Pennsylvania's Invasives list.

In early summer when mugwort is knee high, it looks like chrysanthemums because its leaves are similar -- sharply lobed.  The trick for telling them apart is this:  Look under the leaf. The underside of a mugwort leaf is white (above).

Mugwort leaves (photo by Kate St.John)
Mugwort's lower leaves in August (photo by Kate St.John)

 

By late August mugwort is three to eight feet tall with insignificant green flowers clustered at the leaf joints and at the tips of the stems.  The leaves near the flowers look different. They're linear, not lobed.

Mugwort's insignificant flowerscluster on the stem (photo by Kate St. John)
Mugwort's insignificant flowerscluster on the stem (photo by Kate St. John)

But it isn't beautiful.

In August a mugwort patch looks tall and messy.

Mugwort looks messy where there's a lot of it in August (photo by Kate St. John)
Mugwort looks messy in August (photo by Kate St. John)

 

Wondering what it is?  Flip a leaf.  It's probably mugwort.

 

(photos by Kate St.John)

Primrose Moths

Primrose moths on a primrose, Allegheny County,PA, 6 Aug 2017 (photo by Kate St.John)
Primrose moths on a primrose, Allegheny County,PA, 6 Aug 2017 (photo by Kate St.John)

Last Sunday I found a crowd of pink and yellow moths head down in a common evening primrose.  Bob Machesney identified them as primrose moths (Schinia florida).

I should have guessed their name.

Moths are often named for their host plant and so are these. Primrose moth caterpillars eat evening primrose, biennial gaura and other members of the Evening-primrose family (Onagraceae).  In July and August the adult moths fly at night and spend the day resting on their host plants.  That's why there were so many on one flower.

Keep an eye out this month for beautiful pink moths on primrose and biennial gaura.  Here's a common evening primrose (Oenothera biennis) without a moth in it.

Common evening primrose (photo by Kate St. John)
Common evening primrose (photo by Kate St. John)

Click here to see biennial gaura whose flowers are actually quite small.

And here's what the primrose moth looks like in a museum, mounted to show all its features.  Amazingly its antennae are pink.

Primrose moth specimen, mounted (photo from Wikimedia Commons)
Primrose moth specimen, mounted (photo from Wikimedia Commons)

 

(primrose photos by Kate St. John. photo of mounted primrose moth from Wikimedia Commons; click on the image to see the original)

Gone To Seed

Wild Bergamot gone to seed, late July 2017 (photo by Kate St.John)
Wild Bergamot gone to seed, late July 2017 (photo by Kate St.John)

Is this a daisy-like green flower with six petals?

No.

The green "petals" are sepals. The two lavender and white tubes on the left provide a clue. The central disc used to hold the flowers.

This is wild bergamot (Monarda fistulosa).  When in bloom it looks like this.

Wild bergamot in bloom in 2016 (photo by Kate St.John)
Wild bergamot in bloom, early July 2016 (photo by Kate St.John)

Still don't recognize it?  Click here to see a flower bed full of Monarda fistulosa.

It's a challenge to identify flowers when they've gone to seed.

 

(photos by Kate St. John)

Stiltgrass is Everywhere

Japanese stiltgrass, late July 2017 (photo by Kate St.John)
Japanese stiltgrass, late July 2017 (photo by Kate St.John)

This summer I've found a lot of stiltgrass in western Pennsylvania.

Japanese stiltgrass (Microstegium vimineum) is a native of Eurasia that grows in both sun and shade.  In the 1900s it was used as packing material for shipping porcelain from China to the New World.  Inevitably, it took root in Tennessee in 1919 and is now present in 24 states and Puerto Rico.  In Pennsylvania it's invasive, especially in the woods.

Though grasses are notoriously difficult to identify, stiltgrass has three characteristics that help you figure it out.

(1) Each leaf has a shiny central rib, as shown above.

(2) The rib is off center on the leaf, easiest to see on the underside.

Back of the leaf: Japanese stiltgrass (photo by Kate St.John)
Underside of the leaf shows the off-center rib on Japanese stiltgrass (photo by Kate St.John)

(3) Unlike native grasses, stiltgrass forms a dense carpet on the forest floor that chokes out all other plants.

Japanese stiltgrass, late July 2017 (photo by Kate St.John)
Japanese stiltgrass, late July 2017 (photo by Kate St.John)

When you see dense grass like this, check it for shiny off-center ribs.  Watch this video for more identification clues.

This year I've seen stiltgrass at all the bike trails and even in the woods in Schenley Park.  It looks like a nice carpet until you realize it's invasive.  It's everywhere!

How do you get rid of it?

Deer don't eat it.  But goats do.   Hmmmm.

 

(photos by Kate St. John)

Now Blooming: Hog Peanut

Hog peanut vine and leaves (photo by Kate St.John)
Hog peanut vine and leaves (photo by Kate St.John)

On a sunny day last week I went to Jennings Prairie to see the wildflowers.  My old favorites were there -- dense blazing star, tall sunflowers, culver's root -- but this plant was new to me.

Hog peanut (Amphicarpaea bracteata) is a member of the Bean family (Fabaceae) but its leaves caught my eye because they share some field marks of poison ivy.

Like poison ivy, two of hog peanut's three leaves are asymmetrical and have no stem, the middle leaf has a stem, and the vine is hairy.  Unlike poison ivy, hog peanut leaves are egg-shaped and have smooth edges.  See the difference for yourself by comparing these photos of poison ivy leaves and vines.

Hog peanut got its name because it produces edible beans that are eaten by ruffed grouse, ring-necked pheasants, mice, voles and -- apparently -- hogs.

Most of the beans are produced by its insect-pollinated flowers shown below but some come from self-fertilizing flowers that grow on runners along the ground.

Bumblebee on hog peanut flower (photo by Kate St. John)
Bumblebee on hog peanut flower (photo by Kate St. John)

Although hog peanut is an annual, chances are good that you'll find it in the same location year after year because its ground-based flowers go to seed.

Look for hog peanut in wooded areas along streams and seeps and on floodplains.  I found this one at the "Detour" bridge at the prairie.

 

(Note: The big bridge on the Blazing Star Trail is under construction.  The detour is obvious and easy.)

(photos by Kate St. John)

Common Mullein: Wait Until Next Year

Common mullein (photo by Kate St.John)
Common mullein (photo by Kate St.John)

In July these green and yellow flower spikes tower along our roadsides and waste places.

Common mullein (Verbascum thapsus) is a Eurasian native of the figwort family (Scrophulariaceae) that was introduced to North America.  Because it's biennial both forms are visible right now.

In its first year of life, the plant is a basal rosette of velvety blue-green leaves, 4-16 inches long.

In its second year the rosette sprouts a flower spike, blooms in the summer, sets seed, and then dies.

Here it is in the spring of its second year. The basal rosette is beginning to flower.

Basal leaves with flower bud on common mullein in June (photo by Kate St.John)
Basal leaves with flower bud on common mullein in June (photo by Kate St.John)

And here's a closeup of the flowers:

Common mullein flowers (photo by Kate St.John)
Common mullein flowers (photo by Kate St.John)

Though common mullein only reproduces by seed it's very good at doing it.  Each plant produces 100,000 to 180,000 seeds that are dispersed by wind or animals.  If the seeds don't land in a hospitable place, no problem.  They're viable for 100 years!

Consequently, common mullein is listed as invasive in 20 states including Pennsylvania, Ohio and West Virginia.

Because it only spreads by seed, this plant can be eradicated by hand pulling before the seed sets, then bagging it and disposing of it.  Unfortunately, it's too late in the season to do that now and other methods, such as poison, will only spread its seeds when the plant falls.

We'll just have to enjoy its flowers and wait until next year.

When it comes to weeds, I love procrastinating!

 

(photos by Kate St.John)

Pretty, But …

Jetbead fruits, Schenley Park, July 2017 (photo by Kate St. John)
Jetbead fruits, Schenley Park, July 2017 (photo by Kate St. John)

This Japanese shrub is prized for its pretty flowers and fruits.  Unfortunately it's invasive in forests of the eastern United States.

Jetbead (Rhodotypos scandens) is easy to find in Schenley Park where it was planted as an ornamental.

In the spring I misidentify its four-petaled white flowers as mock-orange because I don't pay attention to the leaves.  Jetbead has opposite, deeply toothed leaves with narrow tips and pronounced veins.

Jetbead in bloom (photo from Wikimedia Commons)
Jetbead in bloom (photo from Wikimedia Commons)

The fruits are unmistakable, though.  When ripe, they form a cluster of four shiny black beads -- jetbeads -- shown above.

We'll look for jetbead tomorrow on my Schenley Park outing.  Meet me at the Westinghouse Memorial Pond.

 

(photo of jetbead fruit by Kate St. John; photo of flower from Wikimedia Commons; click on the image to see the original)

Fairy Candles

Close up of black cohosh flowers, 15 July 2017 (photo by Kate St. John)
Close up of black cohosh flowers, 15 July 2017 (photo by Kate St. John)

In July you'll see white "fairy candles" blooming in the woods.  They're the flowers of black cohosh, raising their spindly stems toward the light.

Black cohosh in bloom, 15 July 2017 (photo by Kate St. John)
Black cohosh in bloom, 15 July 2017 (photo by Kate St. John)

These "fairy candles" are also called "black snakeroot" because the root is black.  Native Americans used the root to treat pre-menstrual symptoms, an herbal treatment that's still in use today.

Black cohosh (Actaea racemosa, syn. Cimicifuga racemosa) looks a lot like mountain bugbane (also known as American bugbane, Actaea podocarpa) because the plants are related.  Mountain bugbane is endangered in Illinois and rare in Pennsylvania.  Get a whiff of the flowers to tell the diffrence:  Mountain bugbane smells good, black cohosh smells bad.

Unfortunately some people dig up both plants thereby killing them and making them harder to find in the wild.  Whether digging is legal depends on the rare/endangered status of the plant and who owns the land. It's legally complicated but ethically simple: Removing shared beauty for private use leads to the Tragedy of the Commons.

 

p.s. U.S. Forest Service has a good article -- here -- about the legality and ethics of taking plants on Federal land.

(photos by Kate St. John)

Keep Eating!

Japanese beetle eating Japanese knotweed, Allegheny County, PA, June 2017 (photo by Kate St. John)
Japanese beetle eating Japanese knotweed, Allegheny County, PA, June 2017 (photo by Kate St. John)

Last month along the Panhandle Trail I paused to look at a wildflower near some Japanese knotweed when I noticed the knotweed was being eaten by Japanese beetles.  🙂

Japanese beetles (Popillia japonica) were introduced to North America by accident in the early 1900s and spread across the continent.  The adult beetles eat leaves, the larvae eat roots.  If you have roses, you've been battling Japanese beetles your entire life.

Japanese knotweed (Fallopia japonica) was introduced as a garden plant but is so aggressive that it chokes out native plants and even grows through asphalt.  As one of the world's worst invasive species, it's such a pest in Great Britain that as recently as five years ago you couldn't get a mortgage if there was Japanese knotweed on the property. (That has since changed.)

Of course I was happy to see these two "Japanese" species together.  The beetles felt so at home on the knotweed that they were mating on it.

Japanese beetles mating on Japanese knotweed, Allegheny County, PA, June 2017 (photo by Kate St. John)
Japanese beetles mating on Japanese knotweed, Allegheny County, PA, June 2017 (photo by Kate St. John)

My hope is that the female beetles will drop to the ground below the knotweed and lay their eggs.  When the eggs hatch the larvae will burrow underground and eat the roots of nearby plants.

Good.  Eat the knotweed roots.  Eat the leaves.  Go on, Japanese beetles.  Keep eating!

 

(photos by Kate St. John)