A Glimpse of Nature - Jewelweed

See what’s happening on the grounds of the Ames Free Library or nearby areas with “A Glimpse of Nature.” Offered by Lorraine Rubinacci, the library's resident naturalist, this weekly photo blog is a gentle reminder to enjoy the wonders that surround us.

A Glimpse of Nature - "Jewelweed"

I am struggling through the sultry days of August, but some species have flourished during this hot, rainy summer. Here’s one that’s currently in its glory: jewelweed.

This profusion of blossoms can be found between the Queset House driveway and the Ames Free Library’s main parking lot. Thousands of individual flowers are vying for pollinators and creating seeds for the next generation. This annual species grows in colonies whose stems help support one another.

Here’s a closer look at the plant and its most obvious feature, its orange trumpet-shaped flowers dangling from delicate petioles, as graceful as ornaments on a Christmas tree. Notice the reddish spots and the recurved spur which holds the blossom’s nectar.

The bluish-green leaves of this plant are soft and flexible and able to repel water in a most lovely fashion. Rain and dew bejewel the leaf surfaces with perfectly-formed droplets. If you happen to pick and twirl a plant under water, the white undersides of the leaves will sparkle silver. You might just be inclined to do this considering where the plant grows.

Jewelweed is widespread throughout the deciduous forests of New England, preferring light shade and moisture. It is common along stream banks and wetland margins, places that will give you an opportunity to do the “sparkle test.” The library’s jewelweed patch follows the course of an intermittent stream. While the stream itself is obscured by vegetation, its path is delineated by this jewelweed “river.” Stand on higher ground near the stage to get a bird’s eye view.

Like its habitat, jewelweed stems are watery -- succulent and somewhat translucent. Sap from its crushed stems has long been used as a remedy for the skin irritations caused by poison ivy and stinging nettles. Here’s a cross section.

While they can break easily, these hollow stems provide sufficient support for this rapidly-growing plant. As an annual, jewelweed needs to accomplish its life work quickly. With adequate moisture and light, it can grow six feet high. The tallest and most robust specimens I ever saw grew over a septic system where I once lived. The central plants in the colony had stems like corn stalks!

Why did I have jewelweed in the center of my backyard? It grew well: the right plant in the right location. Its nectar also attracted hummingbirds who are major pollinators of this species. At the library, the primary pollinators are bumble bees -- many, many bumble bees whose long tongues can reach into the flower spurs. Some crawl into the front of the flowers; others make holes in the spur to get at the nectar. I enjoy watching them feed and am completely comfortable doing so.

Jewelweed’s lush greenery tones down the summer heat for me, and its ornate orange trumpets make me smile. All the same, my favorite aspect of this species is its seed dispersal. Once pollinators have done their work, elongated seed capsules develop. When ripe, the mature pods “explode” with the slightest touch, thereby projecting their seeds several feet away from the parent plant. This is the origin of jewelweed’s other common name, “spotted touch-me-not.” Indeed, this behavior also explains the species’ scientific name: Impatiens capensis. In Latin, “impatiens” means impatient, apparently referring to the plant’s rush to send its seeds into the world. And, yes, these wild North American impatiens are relatives to the commonly-grown garden plant sometimes called “busy lizzie.”

I can’t resist the temptation of petting these plants. Even though I know exactly what will happen, the moment of the dispersal still comes as a surprise. Watch this brief video to see the phenomenon. In the first section, I apply some pressure to a capsule that is not fully ripe. The moment of the rupture is caught on freeze frame, followed by a shot of the seeds and capsule remnants. The second part of the clip shows the dispersal of seeds from a ripe pod in slow motion (10% of normal speed).

Jewelweed is a familiar plant to many people who walk or play outside in southeastern Massachusetts. Yet, as commonplace as it may be, the species has “stories to tell.” I just learned that its trumpet-shaped flowers begin as male and then transform to female. The plant also has a second type of flower that is self pollinating, much like the hidden flowers of the common violet. These and other observable behaviors are described in A Guide to Enjoying Wildflowers by Donald Stokes. You can observe this plant as it continues to bloom throughout summer and early fall. Next time you walk over the Queset foot bridge, take a closer look at where and how it grows. Go ahead . . . touch one of its seed capsules. You’ll chuckle, and seeds will be in place for next year.

At the Library