Pretty berries, right?

Wrong.  You don’t want them!  These are the fruits of mile-a-minute weed (Persicaria perfoliata), an invasive species that earned its name because it grows really fast — up to 25 feet in a single growing season.

Mile-a-minute arrived in Stewartstown, PA from Japan in the late 1930’s and spread from there.  Because birds and animals eat the berries, the plant spreads easily to new and remote locations. I’ve seen it growing on top of Laurel Mountain; Dianne Machesney photographed these berries at Green Cove Wetlands.

Mile-a-minute can take over a sunny spot very quickly and choke out every plant that underlies it.  You can recognize it by its triangular leaves, barbed stems (it’s called a “tearthumb”) and cup-shaped shield leaves at the stem joints.

Because mile-a-minute is an annual with shallow roots you can eradicate it if you’re vigilant.  Put on stout gloves and pull it out.   If it’s gone to seed — as it has by now — collect the seeds first, then pull.

Here’s what to do in a fun video from the Home and Garden Information Center at the University of Maryland Extension.

(photo of fruit by Dianne Machesney, photo of leaves in the public domain from Wikimedia Commons, video from University of Maryland Extension)

Sometimes seed pods are just as interesting as the flowers that produce them.

These many-faceted globes are Wingstem (Verbesina alternifolia) gone to seed.

(photo by Kate St. John)

These beautiful fall crocuses are blooming today near the back entrance of Carnegie Museum and Library.

What a treat to see this vision of spring in September.

(photo by Kate St. John)

Just to give you butterfly folks a jolt… I bet you haven’t seen this butterfly on goldenrod in Pennsylvania.

Canada goldenrod (Solidago canadensis) is native to North America but the butterfly is not.  It’s a Common Bluebottle (Graphium sarpedon) found in Asia and Australia.

It’s nice to know that goldenrod attracts such beautiful butterflies but how did these two get together?

The photo was taken in Japan. The goldenrod was imported.

Unfortunately Canada goldenrod went wild when it got overseas and is now an invasive species in Asia.  It’s such a problem in China that they have eradication programs for it just as we do for Japanese knotweed.

If we could only trade our Japanese knotweed for their goldenrod, we’d all be happy.

(photo by Isaka Yogi on Wikimedia Commons.  Click on the image to see the original.)

Ironweed (Vernonia altissima) has been blooming since July.

I never get tired of its purple color.

(photo by Kate St. John)

Continuing on the theme of strange predators here’s interesting news about a plant that preys on insects.

Nepenthes gracilis is a tropical pitcher plant native to Indonesia, Malaysia and Thailand.  Like all pitcher plants it eats insects by trapping them in the digestive fluid at the bottom of its tubed-shaped pitcher.  The inner surface is slippery when wet to enhance the trapping effect.

This is dangerous for an insect, so why would an ant bother to get near the pitcher opening?  Why would it go under the lid?

Nepenthes gracilis tempts insects with a tasty nectar coating on the underside of the lid.  In fair weather a skillful bug can perch on the edge, eat the treat, and walk away.

But in the tropics it rains often and heavily.  Sometimes insects seek shelter under the lid or are eating underneath it when the rain begins… and then…

Researchers discovered that heavy raindrops prompt the insects’ demise.  The lid is poised like a springboard.  The weight of a raindrop springs the trap and catapults the insect into the bottom of the pitcher.

Sneaky!  Food, shelter and trap.

Read more about this discovery in the PLOS One article.

(photo from the PLOS One article by Bauer, U., B. Di Giusto, J. Skepper, T.U. Grafe & W. Federle 2012, (CC-BY-SA), Wikimedia Commons.  Click on the photo to see the original)

In the winter this flowering vine earns the nickname Old Man’s Beard for its hairy, beardlike seeds.

In August it bears white frothy flowers that drape other plants like a Virgin’s Bower.

Clematis virginiana is blooming now in western Pennsylvania.

(photo by Dianne Machesney)

16 August 2012

August is prime time for observing pokeweed (Phytolacca americana), a tall perennial that’s easy to find in waste places and along roadsides.  Though its name is “weed,” I love its colors.

In winter pokeweed dies back to the taproot but by August it’s 6-10 feet tall with spreading branches.  The succulent stems are stout and reddish with deep green alternate leaves up to 16″ long.  This plant is big.

Pokeweed’s flowers bloom on racemes that curl up while flowering and droop down when heavy with fruit.  This month you can see the flowers and fruits in all stages of development, often on the same raceme.

Here the flowers show five white petal-like sepals and nascent green berries in their centers.  Notice how the stem is pink.  Pink, white, green.

After the flowers are pollinated the green berries grow larger. On this stem the berries are all the same age, but that’s pretty rare.

More often the berries range from unripe green to ripe blue-black on the same stem.  This raceme shows nearly every stage in the berry life cycle.

Ripe pokeberries are a favorite food for catbirds and cardinals, robins and mockingbirds, thrashers and waxwings. When the berries are gone the empty stem puts on a final show in gorgeous magenta.

Like many plants pokeweed is toxic though if properly prepared the young shoots can be eaten in Spring.  The song about eating pokeweed, Poke Salad Annie by Tony Joe White, might lead you to believe lots of people eat it.

Don’t attempt to eat pokeweed until you know how to prepare by it! Everything you need to know is in this video from Edible Mountain on West Virginia Public Broadcasting:

On the plus side, the deep purple berry juice makes a beautiful red dye.

Pokeweed’s colors are a delight at every stage.

(photos by Kate St. John)

Blooming now in Pennsylvania, the evening primrose fully opens at twilight.  Similar species called sundrops are open during the day.

Both flowers are in the Oenothera genus and are masters at opening and closing in response to light.  It takes these flowers only a minute to do it.   Click here to watch one opening.

Evening primroses are hardy and widespread, in fields and along roadsides.  Dianne Machesney found this one at Scotia Barrens.

(photo by Dianne Machesney)

p.s. Monday August 13: It’s cloudy and gray this morning. Evening primroses are open in Schenley Park.