Last Saturday ended up being a gorgeous day for a hike, so we visited the Minute Man National Historical Park, which is essentially a 6 mile long walking and biking trail in the heart of Lexington/Concord. The trail is maintained by the National Park Service, and the visitor center is a rustic-looking building with some excellent historical displays, artifacts and a gift shop.
It seems that peak leaf season is happening right now in Greater Boston, and the path is surrounded by beautiful wooded areas, meadows and wetlands. You’d never know that the suburbs are only a half mile off in any direction.
Along the path are many preserved colonial buildings, mainly farmhouses, barns and pubs that belonged to residents of the Revolution-era Commonwealth. Ample signage provides information about these structures and their inhabitants. We even saw a number of roleplaying actors in complete colonial garb traveling down the path, happy to provide information about the park and its treasures.
But on to the wildlife!
We spotted this Clethra alnifolia in full fall colors near the trailhead. Its fragrant summer flowers had gone to seed, and its leaves were a brilliant yellow. We often plant Clethra as an ornamental species. It’s a great native plant that provides many benefits: bees are attracted to the strongly scented, perfumey flowers, and it survives well in moist soil, making it ideal for planting in wet gardens or near water features. Many cultivars are commercially available as well.
We discovered this brass marker in the ground near the foundation of a historic structure. USNPS MIMA is the abbreviation of the Minute Man Historical Park, but I couldn’t figure out the meaning of the numbers underneath (P40,10 18?).
These seed pods are the notorious fruiting bodies of Arctium kappa, otherwise known as greater burdock, or colloquially, the sticky burr plant. Widely known as the inspiration behind the invention of velcro, the seed dispersal mechanism of this plant is an excellent evolutionary adaptation that allows seeds to be carried for miles by birds and mammals, and even across the Atlantic. Greater burdock has uses in traditional Chinese medicine, and its roots are sometimes used in Japanese cuisine as a type of starchy stir fry ingredient.
The fruiting body of staghorn sumac (Rhus typhina) is as visually striking as burdock is inconvenient. Native to the northeast and planted ornamentally in other places, staghorn sumac blooms in mid summer and then puts on a gorgeous show of foliage and fruit in early and mid autumn. The plant is rich in tannins and has many uses, including as a dye, a tobacco substitute, and a food source. Its clusters of small red drupes can be collected, steeped and sweetened to make an excellent pink lemonade (or so I’ve heard). One of these days I’ll get around to trying it..
More asters! Some parts of the path were surrounded by flushes of white. It’s amazing how well-suited their flowers are to fall weather.
Here’s the seed head of Queen Anne’s lace (Daucus carota), a beloved wildflower from which we get the domesticated carrot cultivar that ends up in our dinners. In bloom, it has an unusual inflorescence known as an umbel, which forms a cluster of tiny white flowers with a single central red flower, colored by the compound anthocyanin–the pigment responsible for the gorgeous red autumn leaves of many species. The purpose of this single flower is to attract a wide variety of insects, and D. carota is often used as a companion plant for crops and gardens.
The roots of D. carota can be collected and used as food when young, but harden off as the plant matures. Care must be used when handling the foliage! Contact with the green bits can cause Phytophotodermatitis, a skin condition caused by compounds in certain plant families that hypersensitize tissue to UV radiation (read: awful sunburns).
It is often confused with the Conium maculatum, poison hemlock, which was famously responsible for the death of Socrates.. but it doesn’t take the wisdom of the ancient Greeks to know that you should always be extra cautious when eating things that you find outside.
Near a stone wall in this idyllic field, we found a large patch of Fallopia japonica, otherwise known as Japanese knotweed. Knotweed is a tenacious and aggressive invasive species in the US, and is listed by the World Conservation Union as one of the worst invasives on a global scale. It’s rhizomes, or the underground portion of the plant equivalent to a root system, grow deeply in soil and spread laterally, frequently disturbing built structures and pavement. The plant can survive in temperatures well below freezing, and it can tolerate a wide range of soil compositions and pH ranges. Thanks to these qualities, F. japonica is extremely resilient and difficult to eradicate, susceptible only to systemic pesticides that are often harmful to the environment.
Despite its reputation as an ecological terror, Japanese knotweed has a variety of useful qualities. Its flowers serve as a source of nectar for bees during early autumn, when few plants are flowering. The stems can be eaten as a vegetable, and forging is sometimes used as a means of controlling the plant.
In Cambridge, Mass, the CBC (Cambridge Brewing Company) is using knotweed as an ingredient in one of their small-batch brews. Named “Olmsted’s Folly,” after the 17th century landscape architect who first introduced the plant to Boston, the beer is supposedly light, dry and tart, and is brewed with cranberries as well. How cool is that! Read more here.
Another member of the Aster family, Cirsium vulgare, or bull thistle, is a striking biennial plant with beautiful purple pincushion flowers. Its flowers provide a rich source of late-season nectar for multiple bee and butterfly species. The visitor here is a bumblebee, a member of the Bombus genus.
Barberry (Berberis thunbergii) is an alluring plant that I’ve written about in other posts. Its colorful, small foliage changes from deep scarlet to green during the growing season, and its tiny red fruits are very festive (and a major temptation for birds). Because of its clumping trunks and tiny thorns, barberry provides an ideal habitat for rodents, in particular field mice, which serve as a major transmitter in the life cycle of lyme disease. For this reason and others, barberry has become a pesky invasive in the northeast, and is no longer planted as an ornamental shrub.
Seas of ferns have put on their beautiful golden fall colors.
Further on, the trail opens into a large wetland, with a large sturdy boardwalk allowing visitors to walk directly through the gorgeous landscape.
Typha latifolia, the broad-leaved cattail or bulrush, is a native inhabitation of wetlands and riparian ecosystems and a New England favorite. As is seen here, the densely packed seed heads open in autumn, dispersing many minute seeds on fine fibrous strands that may travels great distances and can remain viable for quite some time. Because of this, T. Latifolia is able to successfully colonize disturbed areas very rapidly, and is often planted as a method of bioremediation to remove pollutants from soils. This plant has a long history of use in food and medicine by indigenous cultures of the northeast.
The few American elms (Ulmus americana) that we encountered had put on a gorgeous show of golden leaves.
Back in the forest, Briana finds a striking shaggy mane mushroom (Coprinus comatus) growing among the leaves. This species is edible if collected before its gills begin turning black. We left these in place for others to enjoy.
Let’s talk about a phenomenon that brings millions of visitors to New England every year–autumn leaf color. The gorgeous colors that we see are the product of pigments that are present in leaves year round, and are hidden because of the presence of the most important pigment, chlorophyll. Come fall, seasonal changes in daylight duration and quality, temperature, and precipitation will signal to the plant to stop replenishing chlorophyll, leading to the degradation and absorption of the remainder of the green pigment in leaves. The reds and yellows we see are the leftover pigments–the reds produced by a compounds called anthocyanins, and the yellows by carotenoids.
Autumn leaf color is not merely the product of declining leaves before dormancy. According to various theories, the reds and yellows of fall leaves may serve to protect late season foliage from damage caused by both biotic and abiotic sources.
More beautiful poison ivy. It’s really a shame that such an ecologically important and aesthetically pleasing plant is such a nuisance to humans.
Briana discovers a woolly bear caterpillar, the larval form of the Isabella tiger moth (Pyrrharctia isabella). This particular one looks insignificant, but these guys do something so amazing that I’m glad to have the chance to write about them. Unlike most caterpillars that feed and pupate within a short time span–say a couple of weeks or months–the woolly bear is able to overwinter in its larval form. It freezes solid, and wards off an icy death by producing a cryoprotectant in its tissues. Woolly bears in arctic regions are known to feed through many (up to fifteen) winters before pupating. But once they become moths, they have only days to find a mate and reproduce! Nature can be brutal.
As an aside, I love learning about organisms, especially those as humble as the woolly bear, that possess extraordinary evolutionary capabilities! It thrills me to think about the possibilities involved with genetic engineering and the ability to harness these traits to augment other organisms–maybe even humans. I imagine that a resistance to freezing would definitely help the brave souls who one day colonize Mars..
Moving on! After about six miles of hiking (and way too many photos), we decide to call it a day. Near the parking lot, we see the spires of common mullein (Verbascum thapsus) reaching up from the grass. Mullein produces a beautiful, tall spike of yellow flowers from a rosette of low-lying foliage. Its many seeds can persist in soil for decades, even up to a century, before geminating. Despite its abundance of hardy seeds, mullein requires sunlight and open ground for germination, and is rarely considered a nuisance species. It has many medicinal properties as well.
After searching all day, I am very pleased to finally find open milkweed seed pods near the parking lot. Asclepius syriaca is one of my favorite wildflowers. One of the first plants described in North America, A. syriaca is a herbaceous perennial with intricate, fragrant flowers that serve as a source of nectar for many insects. Its foliage is a food source for many beloved species including the monarch butterfly and the milkweed beetle. Studies have shown that the elimination of milkweed colonies with herbicides can directly contribute to the decline in monarch populations. Thus, it is important that we consider milkweed and other native species as alternative to non-native ornamentals in our gardens.
I’ll conclude this post with a familiar image–that of the marred trunk of an American beech (Fagus grandifolia), which, because of its smooth mature bark, will probably retain these carvings for decades. Beech is an important tree ecologically and commercially. It provides hard, dense lumber for humans and is a food source for many insects and animals. Few trees compare to the grandeur of a mature beech, with its deep foliage, spreading limbs and silvery bark.
Like humans, trees dislike having their protective barriers damaged. Beeches are highly susceptible to a range of funguses that quickly colonize wounds and eventually kill their victims. Typically, wounds are caused by predatory insects–but in this case, the culprits are the visitors who have carelessly carved their initials.
This image is bittersweet. We must continue to support the institutions that protect our natural spaces, maintain them, and make them available to us for our enjoyment. But equally important is our obligation to educate ourselves and others as to the impact that our behaviors have on the world around us.
Thanks for reading,
Additional pictures from our hike: