1 June 2025
Sideling Hill CK, Natural processes
Sideling Hill Creek is one of our most beautiful paddling venues. The forest on both sides of the creek was lush and green today, unusual in that the creek has two very different bank profiles—a steep rocky dry cliff on one side where vegetation is typically dry and browned, and a flat moist alluvial plain where the well-watered forest is always lush and green. There were pink and white mountain laurel in full bloom and the rhododendron buds are swelling for their display later in June. Ninebark, a fountain shaped shrub, was covered with off-white marshmallow size flowers. Less common were the exotics which put on such a display on the Cacapon earlier in the week—white MF rose and purple Dame’s Rocket. That is a good thing. Today we were lucky to have Pam’s friend Lynne along. She is a geologist and was willing to interpret the miles of crenellated and folded sedimentary rocks. Thank you, Lynne. Extra points to trips with a geologist along.
We had a fine view of natural history at work on Sideling Hill Ck today. May has been a wet month with storms that left footprints in the river gauge May 3, 9, 13, 21, 27, and 30. The big rain on the 13th pushed the gauge up over 3000 cfs vs a median flow of about 80 cfs. That was evident today where wrack lines and debris in the trees were evident up to 6’ above today’s level.
But the big difference between high water this spring and spring in past years was the extensive physical disturbance. The flooding toppled trees and uprooted woody plants along both banks. We had lots of strainers from both sides. There are now big piles of debris at some river bends and the tree canopy gap over the creek is much larger in some places. Cobble bars have been scraped clean in places and rearranged by the high water. All this is a good thing. Sideling Hill Creek and nearby Fifteen Mile Creek are home to a globally rare plant species called Harperella, an annual flower that grows in rock crevices and gravel bars along the waters edge in clean water streams. The flooding cleared off and rearranged thousands of square feet of cobble bars along the river’s edge, creating growing space for this annual plant that otherwise must compete with established perennial plants. The downed trees and enlarged canopy gaps will ensure higher light levels for Harperella and for all plants growing along the river’s edge, and presumably along nearby Fifteen Mile Creek as well.
Harperella is not a special plant but it is rare and the small populations are widely separated in the southern piedmont. It lives in tiny patches of the landscape that paddlers frequent. It reminds me of the David Quammen short Synecdoche and the Trout (pdf available online or email me; the following piece Time and Tide on the Ocoee River is the back story of one of our favorite boats). The presence of this rare fragile plant is a symbol of the existence of clear clean tumbling streams like Sideling Hill Creek, creeks that flood in the spring occasionally (hooray!!). Even though we will probably never see Harperella in person, we benefit immensely from its presence and should all celebrate its existence.