Green-headed coneflower (Rudbeckia laciniata) is blooming now in western Pennsylvania.

Look for its green head and swept-back yellow petals in open woods and fields.

(photo by Kate St. John)

This night-blooming flower grows like a weed in Arizona.  Here, Donna Memon captured a trumpet glowing in the setting sun.

Datura grows easily in the Arizona desert and is cultivated around the world.  There are currently nine species, many of which are hard to identify because the plant changes its characteristics to suit the growing conditions.  Its common names include jimsonweed, moonflower and angel’s trumpets.

Though beautiful it is extremely poisonous, producing hallucinations, elevated body temperature, tachycardia, severe pupil dilation, unconsciousness and death.  Thus it was surprising to me that it’s called “sacred datura” in Arizona because Navajo and Havasupai shamans used low doses for religious hallucinations.

The proper dose is hard to determine and if you get it wrong you die.  The correct amount varies — even in the same plant — based on age, soil conditions and local weather.  Despite the warnings people try it and, as Wikipedia says, “Few substances have received as many severely negative recreational experience reports as has Datura. The overwhelming majority of those who describe their use of Datura find their experiences extremely unpleasant both mentally and often physically dangerous.”

The angel’s trumpet is beautiful but a deadly way to see angels.

Read more here at Wikipedia.

(photos by Donna Memon)

This flower is blooming everywhere right now but we never notice it.  Its beauty is tiny and the plant is a weed so we pass it by.

Galinsoga or Quickweed is an annual in the Aster family with small daisy-like flowers with five notched petals.  The leaves are opposite and toothed in a jumbled mass below the long, branching flower stems that give the plant a messy “leggy” appearance, 6-18 inches high.

Look closely and you’ll see the leaves and stems are both hairy.  But no one looks closely unless they want to eat it (yes it’s edible).

Here’s what we typically see when walk past Galinsoga on the street.

Once you start looking, Quickweed is everywhere: growing in the sidewalk cracks, sprouting in gardens, covering an abandoned lot where its density makes it pretty.  Local gardeners call it “Pittsburgh Pest.”

It earned the name Quickweed or Raceweed because it produces seed rapidly (7,500 seeds per plant per year) and has many generations in the same season.

When it’s gone to seed it looks like this.

The genus is Galinsoga but what is the species?

Good question!  My Newcomb’s Wildflower Guide lists only Galinsoga ciliata = Galinsoga quadriradiata.  Richard Nugent and Flora Pittsburghensis both identify it as Galinsoga parviflora.  Quadriradiata is from Mexico, parviflora is from South America.  In any case, it didn’t jump an ocean to find us.

But it jumped an ocean to Europe.  Galinsoga parviflora was taken from Peru to Kew Gardens in 1796 where it escaped to the wild and quickly became a weed.

Aha!  Quickweed.

(photos by Kate St.John)

11 July 2015

Here are some pink flowers you don’t see every day.

Indian pipe (Monotropa uniflora) is a parasite in a three-way relationship. It’s lives on a symbiotic fungus that gets its own food from tree roots in exchange for mineral nutrients.

Since Indian pipe doesn’t need chlorophyll the plant is ghostly white and can live in the deep shade of a dense forest.  When Indian pipe blooms the flowers droop downward.

But as soon as they’re fertilized the flowers move into the heads up position.  Esther Allen taught us that this helps the plant disperse its seeds.

Most plants have erect flowers that nod when fertilized.  Indian pipe is backwards in many ways.

Learn more about Indian pipe in this article from the Arkansas Native Plant Society.

(heads up photo by Kate St. John. Heads down photo from Wikimedia Commons; click on the photo to see the original)

7 July 2015

This small yellow-orange vine is a native annual in the morning glory (Convolvulaceae) family that causes trouble for farmers.

Dodder (Cuscata) has virtually no leaves and is not green because it doesn’t have chlorophyll to make its own food.  Instead it’s a parasite that wraps itself closely around a host plant, inserts very tiny feelers called haustoria between the cells, and sucks nutrients out of the host.  Though it starts growing from seed, it loses its soil-based roots when it has found a really good host.

Newcomb’s Wildflower Guide has only one entry for dodder in eastern North America — common dodder (Cuscuta gronovii) — but there are 100-170 species around the world, especially in tropical and subtropical climates.

In Pennsylvania dodder blooms July to October in dense clusters of small white flowers.  According to Wikipedia “the seeds are minute and produced in large quantities. They have a hard coating and typically can survive in the soil for 5–10 years, sometimes longer.”  And therein lies the problem.

Farmers hate this plant because it eats some of the plants we cultivate including tomatoes.  If dodder takes over the best way to combat it is to plant something dodder can’t live on such as grasses or wheat, but it takes a few years before the dodder seed bed is too old to grow.  Hence, dodder has been declared a noxious weed/seed in 49 states.

On the other hand, I’ve rarely seen dodder act invasive in the wild (here’s a thick patch) and tomatoes have developed their own defenses against it.

In the end you might think dodder is good for nothing but in western North America it hosts the caterpillars of the brown elfin butterfly (Callophrys augustinus). (See comments.)

And so goes the circle of hosts.  Dodder eats from its host and, as a host, it is eaten.

(photo by Kate St. John)

I don’t usually write about cultivated flowers but these caught my eye at Phipps Conservatory’s Outdoor Garden.

A Google Image search matched my photo to Clematis jackmanii, a cultivar introduced in 1862 by George Jackman.  Phipps Conservatory was built in 1893 so the plant and the building would be close contemporaries.

The vine is thick with 5-7″ deep purple flowers.

It also has these unusual swirling structures.    Do you know what they are?

(photos by Kate St. John)

p.s. If I’ve misidentified the vine, please let me know!