Twenty one thousand years ago two-thirds of Ohio was covered with a thick layer of ice from the Wisconsin glacier. In what would later be Fairfield County, two adjacent knobs made of Blackhand sandstone successfully resisted this glacial onslaught. Instead of engulfing these knobs, the ice sheet flowed around them on its southward journey that stopped just short of the Hocking Hills. Today they’re known as Allen and Ruble knobs, and they’re the main attraction of the 88 acre Shallenberger State Nature Preserve.
The parking lot is small and shaded by surrounding trees. A trail head opposite the parking lot entrance beckons you to explore further. The 1.5 mile trail consists of two connected loops, one around Allen Knob and a second that skirts Ruble knob. Side trails lead up the steep slopes to the top of each knob.
The glacier dumped debris (known as moraine) around the knob which eventually developed into a rich soil that’s well-suited for agriculture. In contrast there is a very scant layer of soil on the top of these two knobs, but mountain laurel (Kalmia latifoli) and chestnut oak (Quercus prinus) are able to thrive under these conditions. The richer soil along the forest trail below the knobs supports a more abundant and diverse variety of plants.
The 240 foot high Allen knob is the more interesting of the two. It has a wide plateau with rocky outcroppings and steep vertical drop-offs.
We visited at the end of May. Due to the unseasonably warm weather we have had this year, the mountain laurel was just finishing its blooming season. The surrounding forest was lush and green, but if you’d like a scenic view of the surrounding plains, it might be better to visit before the foliage has emerged or after it has fallen. Spring wildflowers are said to abound here, but to see these you need to arrive at the nature preserve in early spring.
- ODNR: Shallenberger State Nature Preserve (with trail map)
- TrekOhio: An Overview of Hiking Trails in Fairfield County
- TrekOhio: Fairfield County Parks & Nature Preserves
To reach Shallenberger Nature Preserve, exit US-33 (south of Lancaster) onto US-22 East. Immediately, turn left onto Beck’s Knob Road for a quarter-mile. The parking lot will be on the right. You will see a brown sign identifying the preserve.