Pickle Springs Natural Area

Pickle Springs Natural Area lies in Ste. Genevieve County, about an hour south of St. Louis. Like Hawn State Park, the geology of this area and its effect on the flora have resulted in a unique collection of geologic features and plants found in few other places. The Lamotte sandstone outcrops that dot the landscape were formed nearly half a billion years ago when sand deposited in an extensive maze of braided river channels was cemented and buried under younger layers of limestone and dolomite formed from deposits on the floors of ancient seas that covered the interior of the continent. Later, the periods of uplift that created the St. Francois Mountains and resulting erosion of overlying strata once again exposed the sandstones at the surface. Millions of years of water, ice, rain, wind, and plants have further shaped the exposed sandstones, creating fanstastic shapes and formations and cool, deep canyons. The weathered sandstone created acid soils which support many unique plants. During the ice ages, northern plants and animals moved into the area ahead of the advancing glaciers. Mammoths roamed the landscape grazing on the northern vegetation supported by the area’s acid soils. Eventually the ice retreated, and so did the mammoths. But many of the plants remained – able to hang on in the cool, moist canyons long after the mammoths that once roamed these canyons disappeared. Because of this unique concentration of rare plants and geologic features, the area has been designated a Missouri Natural Area and a National Natural Landmark.

Yesterday I hiked the aptly-named ‘Trail Through Time’ with my family. This 2-mile trail is one of the most “feature-packed” trails in the state, with something to look at around almost every bend. Almost immediately the trail leads to the Slot, the result of a vertical fracture in the Lamotte sandstone that was loosened by leaching and then widened by erosion. The unique partridge berry (Mitchella repens) was seen on the moist, vertical walls of the rock, growing among strange holes, pockets, and ridges that formed as a result of the sand grains being variably cemented.


A short distance from The Slot lie Cauliflower Rocks – large moundlike formations (also called hoodoos or rock pillars) formed from jointed or fractured sandstone that undergoes deep solutional weathering followed by erosion and weather-mediated shaping. Hoodoos occur primarily in this type of rock due to its granular, variably cemented and cross-bedded matrix.


On the south side of Cauliflower Rocks lies a special type of buttress arch called Double Arch. It occurs at almost a right angle to the adjacent rock outrcrops, suggesting formation along a set of fractures running perpendicular to the main fracture trend of the area, but the precise details of its formation remain a mystery.


After leaving Cauliflower Rocks the trail descends steeply into a deep valley, at the bottom of which lies Pickle Creek just below its origin in a box canyon south of the Natural Area. Lush vegetation in this cool, moist valley contrasts with the stark rocks seen earlier.


The creek is fed by a series of seeps, allowing the valley to remain moist even during the dry summer months, and along with the acid soils support a unique plant community. Lush colonies of ferns (I believe this is Polypodium virginianum L.) covered the rocks adjacent to the creek…


…while this rattlesnake plantain orchid (Goodyera pubescens) was seen in a colony growing at the base of a black oak tree (Quercus velutina) just above the creek.


Mosses and lichens were also abundant in the valley. This little hair cap moss (Polytrichum sp.) with its distinctive fruiting structures was growing in a colony at the base of another black oak tree. The members of this genus prefer acidic environments.


Further ahead, along Bone Creek, several colonies of wooly aphids (family Aphididae) were seen on the branches of a small hop hornbeam tree (Ostrya virginiana).


The highlight of the hike had to be in Spirit Canyon at Owl’s Den Bluff. The horizontal layers of sandstone, each deposited on the steep downstream slopes of sandbars, are clearly visible in the towering bluff face. At the bottom lie bluff shelters – formed where lower sandstone layers collapse due to weathering or leaching, and where native Americans almost surely camped out. The sun never reaches parts of these shelters, providing ideal conditions for a variety of mosses and liverworts – many of which are known only from this area. Fallen boulders and collapsed portions of the bluff face provided photo opps for the daring…


…and good exploring for the nimble.


By now, the trail has passed the halfway point and is looping back to the west, where it ascends to Dome Rock Overlook. Along the way, a fascinating variety of lichens, including reindeer lichen, covers the forest floor where they are supported by the acid soils.


Dome Rock Overlook is a the largest hoodoo complex in the Natural Area. The thin soils and exposed conditions create a harsh, dry, windswept environment that only the hardiest of plants can withstand. Only a few small blackjack oaks (Quercus marilandica), shortleaf pines (Pinus echinata), and farkleberry (Vaccinium arboreum) survive here. Despite their small size, some of the trees growing here are at least 150 years old.


The trail descends from Dome Rock Overlook and passes underneath, providing spectacular views of the sheer rock face below the overlook. The trail completes its descent back into Pickle Creek Valley, where Pickle Spring can be seen. This small, permanent spring – an unusual feature in sandstone where seeps are more common – was an important source of water for early settlers.


Further along the trail lies one of the areas most unusual features – Rockpile Canyon – formed some 50 years ago (a fraction of a second in geologic time) when part of a sandstone bluff collapsed in a rumble, leaving behind a sheer bluff face and a jumbled pile of large boulders. A short spur in the trail leads to the head of a small box canyon, where some of the 20+ ice age relict plant species can be seen growing in the acid soils and cool, moist canyon walls.

Near the end of the loop lies Piney Glade, an area where the exposed sandstone bedrock once again creates a dry, harsh environment. Poverty grass and little bluestem grow in small, shallow pockets of soil scattered amongst stunted shortleaf pines and blackjack oaks – creating a small prairie surrounded by a sea of forest. All three forms of lichens can be found on the rocks and soils of the glade – the aptly named crustose lichens cling tightly to rock surfaces amongst foliose (leafy) and fruticose (branched) lichens.

Rockwoods Reservation, Lime Kiln Loop Trail

Rockwoods Reservation, in western St. Louis Co. is one of the oldest Conservation Areas in Missouri (est. 1938). It contains nearly 2,000 acres of high quality upland forest and a small prairie restoration plot. Despite its proximity to St. Louis and the numerous hiking trails it offers, I haven’t explored this area very much. We had a winter storm move through the area yesterday, dumping about 7 inches of snow over the area. Deep snows are not common in St. Louis, which typically has more open winters, so today offered the perfect opportunity to start exploring this area in a rare wintery setting. My daughters came with me to explore the 3.25-mile Lime Kiln Loop Trail.


The first half mile of the trail follows alongside a spring-fed creek. As we enjoyed the serenity of the snowy landscape, a belted kingfisher flew into a nearby tree, where it paused briefly before zipping off in a chatter. The spring itself offered a beautiful contrast between the green aquatic plants that populate the spring’s exit and the surrounding white blanket.


After the spring, the trail started traversing up the hillside into a mesic upland forest dominated by oaks and hickories. The high canopy of this mature forest resulted in a sparse understory, affording spectacular views back down through the draws from which we came.


The girls were full of energy at this point, so they kept running ahead on the trail and then waiting for me to plod my way back up to them. Eventually they learned their lesson though – everytime they ran up ahead they would get hot and want to take their coats off, then they would get cold and have to put them back on.


There were some drier forest types closer to the bluffs where eastern red cedar (Juniperus virginiana) became more abundant. I coaxed them to pass underneath this one, then whacked it with my hiking stick as they did so. Shocked indignation soon gave way to tenacious efforts on their part to ‘get me back’. Failing that, they redirected their efforts to ‘getting’ each other.


The games eventually gave way to quiet enjoyment of the astounding beauty of the forest. Existing tracks in the snow told us we were not the first to enjoy the trail today, but we didn’t see a single soul all day – it was easy to pretend that we were the only people in this wood. These snow-covered, hollow tree stumps reminded us of tubular sponges.


As the trail descended back down into the valley it passed through these dolomite outcrops supporting a dry upland forest dominated by eastern red cedar and blackjack oak (Quercus marilandica).


Near the end of the trail, we ran across this little spider – actively crawling on the surface of the snow with temps in the mid-20s. I half-jokingly suggested that maybe this was some kind of ‘snow spider’. My 8-yr old daughter thought that seemed likely, then suggested that when we got home we could get online and go to http://www.spider.com/ and type ‘snow spider’ to see what it said. I told her I thought that was a great idea! Alas, that website (and http://www.spiders.com/) lead to a couple of IT company websites, so that was no help. Fortunately, I was able to find something that looked similar – a wolf spider in the genus Gladicosa – on BugGuide. I told Madison her suggestion worked ūüėČ


The lime kiln for which this trail is named was built in the mid-1800’s by a wealthy businessman, who used it to produce lime for mortar construction of homes in nearby St. Louis. The kiln, 12-ft wide at the base and 40-ft high, was built next to the hillside to allow limestone (quarried nearby) to be dumped in at the top. Locally cut firewood was loaded into the arches at the bottom on each side, which heated the kiln to 800¬įF, converting the stone to lime which was removed from the opening at the bottom in front. Vertical expansion joints on each side in the center allowed for expansion of the stone during heating.


This was the second hike in the past few weeks that I’ve taken with the girls, and like last time they had an absolute ball! Of course, naturalist that I am, it pleases me that they enjoy the outdoors so much, and I’m quite impressed that they hiked such a distance with no complaint. The area offers several additional hiking trails ranging from 1.5 to 2.2 miles in length. At only a 15-minute drive from our house, I look forward to exploring the rest of Rockwoods trails with them.

Ozark Trail, lower Trace Creek Section

The Ozark Trail is a part of a vision, conceived in 1977, to build a scenic and varied route through the Missouri Ozarks, stretching from the St. Louis metropolitan area southwestward to the Arkansas border, eventually connecting to the Ozark Highlands trail–creating a 700 mile through-trail. Almost 550 miles of trail have been completed, with 350 miles in Missouri.
Ozark Trail Association

My friend Rich and I have been hiking sections of the Ozark Trail for several years now. So far, we have completed ~175 miles, and we hope to eventually hike the entirety of the trail. Yesterday we hiked the 11.5-mile southern stretch of the Trace Creek Section, starting at the Hwy DD crossing in Iron Co. and finishing at the Hwy A trailhead, where the Trace Creek Section joins the Bell Mountain portion of the Taum Sauk Section. The first few miles traversed relatively mild terrain as we followed the Telleck Branch, but after crossing the upper reaches of the Big River the terrain became progressively more rugged. The trail ended with a spectacularly steep descent down to Ottery Creek at the foot of Bell Mountain.

It was a gray day with light drizzle and increasing fog. The air was heavy with moisture, but with temperatures in the upper 30s and only light winds it didn’t feel too cold. While many sections of the Ozark Trail offer spectacular vistas overlooking the regions many spring-fed rivers, few such vistas are found on this section. What we did see were bright green lichens on rocks, on oak trunks, and on the ground underneath pines, small openings in the forest eerily shrouded in fog, and a variety of ferns along stream banks and in rock crevices, dripping with moisture. It rained lightly at one point, forcing us to break out our ponchos, but the rain didn’t last and we were able to stow the ponchos for good afterwards. It was a serene, beautiful experience with not another soul in sight during the entire day. The solutide contributed as much to the splendor as did the visual beauty. Following are some pictures from the day:

A foliose lichen plasters the surface of a rock outcrop

Closeup of the above, showing an highly convoluted 3-dimensional structure

I believe this is type of “reindeer lichen” – Cladina sp. – growing in a colony on sandy soil underneath a pine tree

Close up of the above, showing the intricacies of its fruticose structure

Water hangs heavy from leafless petioles of a downed oak tree

One of the shelf or crust mushrooms, growing on the trunk of an oak tree

Closeup of the above