I had been aware of the Island, having seen it on maps and having ridden by on the towpath but became much more conscious of it during a meeting of the Botanical Society of Washington last year. Chris Lea was doing a presentation about the fluvial influences on plant communities in the Potomac Gorge. Some of his research had been conducted on Ruppert's and because of this, some folks from Sycamore were in attendance.

While talking to them after the meeting, and mentioning that it would be wonderful to be able to explore the plant life of the island, Doc invited me to come out and visit some time. I kept it in mind, but the right time never seemed to arise. But this spring, I started looking in on the Caretaker's log occasionally. I noticed a couple of mentions of an abundance of Phlox that had started blooming and which was very fragrant. I decided to email Doc with the suggestion that perhaps these plants that were blooming were instead Dame's Rocket (Hesperis matronalis) and not Phlox.

He inspected them and confirmed my suspicion that the flowers in question had four petals, which is characteristic of the mustard family of which Dame's Rocket is a member. It's not native to the U.S. but rather to Europe where it was said to be one of Marie Antoinette's favorite flowers. (Phlox would have had five petals.) While essentially a spring flower, a handful of plants usually continue to bloom a bit through the late summer.

Doc renewed the invitation to come out to the Island and I decided to make a point to get out there! And so, though I missed the spring flora, I was treated to a treasure of summer flowering species on a couple of recent trips I've made to the Island.

Some flowers prefer wet feet

The intense scarlet of the Cardinal Flower makes this beauty easy to spot near the water

One of the most spectacular flowers one can see on the Island in late summer is the Cardinal Flower (Lobelia cardinalis). Its irregular tubular flowers, with two lobes above and three below, are very attractive to butterflies and hummingbirds, though not to cardinals. The Island is also home to its somewhat less showy cousin, the Great Blue Lobelia (Lobelia syphilitica). As you may imagine from the name, this plant has a history of medicinal use.

The showy Halberd-leaved Rose Mallow is also found around the Island's edges.

Another very attractive genus, Hibiscus, is represented by two different species. The Rose Mallow (Hibiscus moscheutos) as well as the Halberd-leaved Rose Mallow (Hibiscus laevis) can be found at the river's edge at various places around the Island. If you have ever eaten Okra, you have eaten a close relative of these lovely plants.

Late summer brings forth a profusion of members of the Daisy family

Elephant's Foot grows next to the wooden walkway by the clubhouse

Elephant's Foot (Elephantopus carolinianus) can be seen growing very close to the clubhouse. Its somewhat rough leaves come out long in advance of the time it flowers. The bluish-purple bloom consists of many small flower heads which rest on a leafy green bract. Like the Ironweed (Vernonia noveboracensis) and the Eupatoriums, it does not have a typical daisy-like appearance.

White Snakeroot, here in a bouquet with a Morning Glory has a poisonous nature.

An array of Eupatoriums is in evidence at this time of year, from the towering Joe Pye Weed (Eupatorium sp.); the attractive violet-blue Mistflower (Eupatorium coelestinum); Boneset (Eupatorium perfoliatum) which is reputed in folk medicine to be able to help broken bones heal; to the very common White Snakeroot (Eupatorium rugosum) and others. White Snakeroot is thought to have been responsible for the death of Abraham Lincoln's mother. In past times, milk sickness was quite a problem. Many people were sickened or died after consuming milk from cows that had a large amount of this plant in their diet.

Sneezeweed was used by American Indians and in folk medicine. It contains the Lactone, Helenalin, which has shown significant anti-tumor activity in the cancer screening program at the National Cancer Institute.

Yellow Sneezeweed (Helenium autumnale), has wedge-shaped yellow rays and a prominent dome-like center disk. The powdered disk flowers and leaves of this plant have been used in the past as snuff which accounts for its name.

The Island has vines too

Passion Flowers produce passion fruits.

I was excited to see that the Yellow Passion Flowers (Passiflora lutea) were in bloom as I had never before seen this species in flower. The common name was given to its more showy relative Passiflora incarnata by early Christian missionaries who felt they saw the passion of Christ symbolized in the complex and showy flowers. This perennial vine is said to be great for attracting butterflies to your garden.

Despite its name, Bur-cucumber bears no resemblance to what we ordinarily think of as a cucumber. (The prominent leaf to the left is not Bur-cucumber, but Japanese hops.)

Also thriving on Sycamore is a native member of the Squash family. The One-Seeded Bur-Cucumber (Sicyos angulatus) has small greenish white flowers and a fruit covered with barbed spines. However, another vine was an unwelcome sight. I spotted a bit of the triangular leaved Mile-a-Minute Weed (Polygonum perfoliatum), a very problematic and fast-spreading invasive from Asia. I pulled up a little but one really needs to have gloves to go after it because of its prickles.

Asiatic Dayflower (Commelina communis) Linnaeus named this genus after a family of Dutch botanists, two of whom attained prominence in their field while a third died before accomplishing anything in botany. He noted that Commelina has flowers with 3 petals, 2 of which are showy, while the third is not at all conspicuous.

Water Willow (Justicia americana) is listed as a weed by the Virginia Cooperative Extension, but as an endangered plant in Quebec. Wildlife agencies are using this plant to create or restore wetlands because it is an important fish habitat and is also very adaptable. It has opposite leaves, which have a distinctive white midvein that runs the length of the entire leaf. They start blooming in early summer and continue into the fall. The plant forms large colonies along riverbanks and in ponds.

Kathy Bilton is a field botanist who delights in wildflowers. She lives about 65 miles up the towpath from the Island.

Click here for the full collection of Late-Summer Wildflowers pictures.