I went down to the Roaring Run Trail for a bike ride both Saturday and Sunday of Labor Day weekend. On Saturday I rode with Rob Bridges, and on Sunday I rode while Deborah walked. The edges of the trail are well covered with newly fallen leaves (mostly red maple, black cherry, and sycamore). August has been very dry (after our near record-breaking wet May, June and July), and the sudden shedding of leaves is probably a moisture conservation response by the trees. We are four weeks, at least, away from true autumn leaf fall.
There were very few birds out along the trail for these two rides. The heat and the time of year selected against seeing very much. The scarlet tanagers, wood thrushes, Baltimore orioles, and rose-breasted grosbeaks that were the summer highlights along the trail have probably all started their fall migration treks to South America (although a few scarlet tanagers (in their yellowy fall plumage) along with some thrushes and a grosbeak were seen in Harrison Hills Park over Labor Day weekend by Jim Valimont of the Three Rivers Birding Club, and just last weekend Deborah and I saw an orchard oriole out in our back yard). Some cardinals and a couple of bluebirds were all I saw on my rides. The Harrison Hills bird observations indicate that fall warblers migrating through our area, but you need to get out early in the day to see them.
About a mile down the trail a three foot long black rat snake emerged from the edge leaf pile and quickly slid out in front of Rob’s bike. We both stopped to give the snake plenty of time and room to get over to the river side of the trail. Black rat snakes are a bit cranky this time of year and frequently coil up and strike out at good Samaritans who try to help them cross trails and roads. In a couple of weeks they will start to den up in their overwintering sites (inside hollow logs, rock crevices, etc.), but we need to watch any “stick-like” shape on the trail today. We wouldn’t want to run anyone over.
The edges of the woods all along the trail were framed by patches of yellow goldenrod, yellow and orange jewelweed, white snake root, and blue mistflower. Tall, purple flower clusters of Joe Pye weed stood above many of the edge displays, and the scattered, pink flower stalks of Pennsylvania smartweed filled in their bases. In many places the exotic invasive Japanese knotweed with their drooping lines of white flowers formed a tall and tight monoculture literally shading and choking out all of the other plant species around it. Golden rod, though, (called “summer’s end” in England) is the main flower along the trail.
There are twenty native species of goldenrod (genus Solidago) in Pennsylvania and another hundred plus species around the world. Solidago species have an amazing ability to crossbreed with each other and, so, close examination of any goldenrod patch is sure to reveal a wide range of types of individuals. Goldenrod’s coincident flowering with the onset of the “hay fever” season has led some to assume that its pollen was the cause of this late summer malady. The goldenrod pollen, though, is very large and sticky and is dispersed not in the wind but on the bodies of pollinating insects (we watched swarms of bumble bees and honey bees flying around the goldenrod stands and saw elegant soldier beetles (covered with pollen grains) climbing up and down the stalks). The absence of wind dispersal makes this pollen a very unlikely contributor to “hay fever” allergies. “Hay fever” is mostly an allergic reaction to ragweed (Ambrosia spp.) and its great, airborne clouds of allergenic pollen. Scattered among the goldenrod are numerous, very unassumingly flowering, ragweed plants.
The honey that the honey bees make from golden rod, by the way, is dark and delicious! The bees can even make a great fall honey from Japanese knotweed (At last! There is something good to say about knotweed!). I just got a jar of some of this dark, rich honey from my Penn State Colleague, Gary Heberling. It is wonderful on toast in the morning!
There were two recognizable species of jewelweed along the trail. Both have the same small, very distinctive, trumpet-shaped flower, but one species grows quite tall and has yellow flowers (probably Impatiens pallida or the “pale jewelweed”) while the other species is shorter and has orange flowers (probably Impatiens capensis or the “spotted jewelweed”). Dense mixed stands of both species border side clearings and extend back into the shady areas of surrounding woods. Jewelweed is widely thought to be a natural remedy and preventative agent against the delayed hypersensitivity reaction triggered by skin contact with the oils of the poison ivy plant (there is a lot of poison ivy along the trail, too!). There have been a number of controlled studies looking into the influences of the leaves and fluids of jewelweed on skin rashes, but none of them have clearly demonstrated any effective anti-inflammatory or even any anti-pruritic (anti-itch) impacts. There is some suggestion, though, that chemicals in the jewelweed fluids may very subtly alter the molecular shape of the poison ivy oils and, possibly, make them slightly less effective as a trigger for their delayed hypersensitivity reaction.
White snake root (Ageratina altissma) is a member of the traditional Eupatorium group (as is blue mistflower (Conoclinim coelestinum) and the tall, purple-flowered “Joe Pye weed” (Eutrochium spp.)). All of the Eupatoria are very poisonous to animals. The poisons in white snake root can be transferred to the milk of a cow (or any other lactating mammal for that matter) and can cause the syndrome called “milk sickness” in anyone who consumes that milk. Milk sickness is a very serious and potentially fatal condition. Extirpation of this plant from areas inhabited by grazing animals is extremely important. Grazing animals are especially likely to consume white snake root during drought years as failing pastures force them to forage in less optimal vegetative habitats.
On both bike rides I went up to the small waterfall about four miles down the trail. Rob noted how quiet the waterfall is now and that there is barely a trickle of flow in its creek. This summer the roar from the waterfall actually had made it hard to talk while standing in the clearing above it. The indigo buntings which were regulars up here all summer have, like their fellow migrants along the trail, departed for South and Central America (although some were spotted in Harrison Hills Park! It’s amazing what you see when you look!). Two monarch butterflies fluttered past. It’s time for them to start heading south, too!
Happy Autumn, everyone!