Spring Unfolding

For many people, spring is their favorite time of year—the long, cold winter having given way to warmth, sunshine, and flowers. I love spring as well but find myself frustrated sometimes by its Jekyll and Hyde nature. This spring was particularly frustrating—the cold and rain seemed at times interminable, delaying the onset of the spring flora several weeks past normal. Once the sun finally did appear, the entire forest exploded in a cacophony of simultaneous leaf and bloom. Plant phenologies were so compressed that there was almost no time to appreciate the season before it was over. Nevertheless, as I waited patiently for those warmer days, I was still able to find beauty in the pre-bloom forest among its nascent leaves—their development put on hold for the time being but taking on an almost floral quality in the absence of the true flowers that they preceded. As a student of wood-boring beetles, I’ve had to become also a capable botanist, at least with regards to the woody flora, and pride myself on being able to identify trees not just by their mature leaves, but also their wood, bark, growth habit, and natural community—characters that are always available when leaves may not be (as is often the case with dead trees). Nascent leaves, on the other hand, are like flowers—ephemeral and often colorful. One must make an effort to see them, but it is effort well spent.

The photos below were taken on a cold, overcast day in late April at Holly Ridge Conservation Area in extreme southeastern Missouri. How many of them can you identify to species? This is an open challenge (i.e., no moderation of comments), and the first person to correctly identify all six will be declared the winner (remember, spelling counts!).


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Copyright © Ted C. MacRae 2013

Blackjack oak “flower”

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This blackjack oak (Quercus marilandica) was found on one of southeastern Missouri’s finest sand prairie relicts a couple of weeks ago on my ‘Annual Birthday Season Opener Bug Collecting Trip.’ Growing near the edge of the prairie at the transition to dry sand forest (Nelson 1985), the arrays of soft, red, newly-expanding leaves at each branch tip had a distinctly floral quality to them. Of course, as with all oaks, the actual flowers of blackjack oak are much less conspicuous, with the staminate (male) flowers borne on drooping catkins, the pistillate (female) flowers on separate spikes on the branch, and pollination accomplished by wind.

Missouri is oak country – nearly a quarter of North America’s 90 oak species (Nixon 2009) occur naturally within the state. This high diversity is explained partly by Missouri’s ecotonal continental position – straddling the east-west transition from the great eastern deciduous forest to the western grasslands. The boundary between these two great biomes is a dynamic, ever-changing interdigitation of woodland, savanna, and prairie that ebbs and flows with the prevailing climatic conditions. Unlike the more mesic forests further east, these dry woodland habitats were often subjected to fire during presettlement times – to which oaks in general (and blackjack oak in particular) are supremely adapted with their thick bark and ability to resprout repeatedly after being burned or grazed back. Sadly, the suppression of these fires post-settlement has caused many of these unique, fire-mediated natural communities to shrink drastically amidst a choking growth of junipers (“cedars” ’round these parts), maples, and other fire-intolerant species. Only on publicly owned preserves and a few private parcels under progressive ownership (such as the sand prairie relict where this photograph was taken) is fire once again shaping the landscape.

Oaks are among my favorite trees, and among the oaks I have several favorites. White oak (Quercus alba) – tolerating many forest types but forming nearly pure stands in high-quality, mesic sites, its tall symmetrical crown, pale bark, and brilliant fall colors are unparalleled among Missouri’s other oaks. Post oak (Q. stellata) as well – lacking the elegance of white oak but achieving its greatest character in fire-adapted savannas and open woodlands as squat, gnarled, massively-trunked trees with broad, spreading crowns¹. Blackjack oak has none of these qualities, yet somehow, it is still one of my favorite Missouri oaks. Stunted and gnarled (‘scrub oak’ to some), it occurs mostly in sandstone and limestone glades, savannas and woodlands on dry, nutrient-poor soils that support few other tree species. The dark green of its tough, waxy (to limit the loss of water), pear-shaped leaves contrasts beautifully with its rough, blocky, almost black bark. Blackjack oak has virtually no timber value, although it is sometimes used for charcoal and firewood. Nevertheless, for me, it is almost an icon for the unique natural communities in Missouri in which it occurs – communities that face ever-increasing pressure from human and forest encroachment.

¹ Please refer to this lovely essay about post oaks in Missouri, by the talented Allison Vaughn.

REFERENCE:

Nelson, P. W. 1985. The Terrestrial Natural Communities of Missouri. Missouri Natural Areas Committee, Jefferson City, 197 pp.

Nixon, J. C.  2009. Quercus in Flora of North America, Vol. 3.

Copyright © Ted C. MacRae 2009

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Trees of Lake Tahoe – The Deciduous Trees

Alder, Maple, and Nuttall’s Flowering Dogwood make beautiful bowers over swift, cool streams at an elevation of from 3000 to 5000 feet, mixed more or less with willows and cottonwood; and above these in lake basins the aspen forms fine ornamental groves, and lets its light shine gloriously in the autumn months.–John Muir, The Mountains of California (1894).

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This is the third installment of a “Trees of Lake Tahoe” series summarizing the trees of Tahoe Basin. The basin forests are, of course, dominated by a diverse assemblage of conifers – eleven species in all.  These were covered in parts 1 (Trees of Lake Tahoe – The Pines) and 2 (Trees of Lake Tahoe – The “Other” Conifers ) of this series.  Yet, despite this coniferous domination, the 14 species of deciduous trees¹ that occur in the Tahoe Basin is three more than the number of coniferous tree species.  These deciduous tree species will be covered in this third and final part, including the nine species I was able to locate on my recent visit to the area back in mid-March.  Because of the timing of that trip, the trees will be discussed from a decidedly wintertime perspective that makes species identifications a little more challenging compared to the coniferous species.

¹ Admittedly, I use the term “tree” in the broadest sense, since many of these species might better be described as “tree-like shrubs” or “shrubby trees,” often representing only the largest examples of genera whose members include a number of true shrubs.  Only a handful of these species routinely form large, unmistakably tree-like forms, the largest of which still pale in comparison to the coniferous giants that dominate the basin.

Family SALICACEAE

This family of dioecious plants (male and female flowers on separate plants) is represented in the Tahoe Basin by two genera.  Two species of Populus occur here, and both decidedly trees in form.  Most of the nine species of Salix that grow in the basin grow only as shrubs, while two of them sometimes form distinct trees.

Quaking aspen (Populus tremuloides)

…in winter, after every leaf has fallen, the white bark of the boles and branches seen in mass seems like a cloud of mist that has settled close down on the mountain, conforming to all its hollows and ridges like a mantle, yet roughened on the surface with innumerable ascending spires.–John Muir, Steep Trails (1918).

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Quaking aspen is one of the most unmistakable trees of the Tahoe Basin – regardless of the season.  Famous for its shimmering foliage during summer and blazing fall colors, it is equally distinctive during winter when its smooth, creamy, greenish-white trunks stand in stark, leafless contrast to the dark green coniferous foliage that cloaks the landscape.  Thick stands of this species are common in moist meadows and stream margins, with stands typically representing clonal colonies of genetically identical trees sprouting from a common root mat.  Although another species of Populus does occur in the basin (black cottonwood – see below), that species is not nearly as abundant as quaking aspen and lacks its distinctive smooth bark.

The second photo above shows some of the few, still-clinging leaves that I found, unremarkable in senescence but showing the flattened petioles that cause to summertime leaves to flutter and quiver incessantly with the summer breezes, alternately flashing their bright green upper surface and silvery underside.

Black cottonwood (Populus balsamifera ssp. trichocarpa)

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Black cottonwood is the largest American Populus and the tallest non-conifer in western North America.  Growing throughout the cool, moist Pacific Northwest, it is at its elevational limit in the Sierra Nevada along moist streams and lakeside habitats in the lower Tahoe Basin. The wonderfully knowledgeable Forest Service worker, who helped me greatly in my quest to locate all of the basin’s conifers, was skeptical about my chances of finding this species; however, while hiking the Rubicon Trail at Emerald Bay State Park I spotted the unmistakable, deeply furrowed, gray bark of this close relative of our own eastern cottonwood (Populus deltoides).  Examining the twigs revealed the large, pointed buds, sticky with resin, and a few clinging leaves whose wide, ovate shape confirmed the species’ identity.  It was the only black cottonwood I saw in the basin, although surely others exist throughout the basin at lakeside elevations.

Willows (Salix spp.)

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As a group, willows are easily distinguished from the other deciduous trees and shrubs that occur in the Tahoe Basin.  However, discriminating among the several species can be quite difficult, even for trained botanists.  Winter is not the best time to try to identify willows, as many species are distinguished by characters of the foliage and flowers.  In some cases, examination of both male and female flowers is required – frustrating since they are borne on separate plants!  Wintertime characters normally useful for other plants such as bark and twig color are rarely informative for different species of willow, and even growth habit as trees or shrubs can vary greatly within species depending on elevation and available moisture.  All of this is a long-winded way of saying I don’t know which or how many species of willow I observed in the Tahoe Basin.

p1020705_2p1020707_2According to Graf (1999), there are nine species of willow in the Tahoe Basin; however, only two of them are trees – the abundant shining willow (S. lucida spp. lasiandra), and the more drought-tolerant Scouler’s willow (S. scouleriana).  The remaining seven species are shrubs that rarely exceed 10-12 feet in height.  Indeed, one of them – arctic willow (Salix arctica) – grows no more than 4 inches tall, occurring in seepy slopes and along lake and stream margins in the subalpine zone at Carson Pass.  Most of the willows I observed were at lower elevation along the shore of Emerald Bay and in the wet meadows around South Lake Tahoe and Spooner Lake and were growing as large shrubs or small trees and exhibited either bright yellow or red bark on the year-old branches, turning to smooth gray on older branches.  I don’t know whether these represent one or more species, or if they even represent one of the two arborescent species, but I suspect the yellow-twigged species may represent Lemmon’s willow (S. lemmonii), one of the shub species and Tahoe’s most common willow.  Perhaps a stretch goal for next year’s trip could be to find and distinguish all nine Tahoe Basin willow species, but realistically I would settle for knowing for sure what species the plants in these photographs represent (although I definitely would like to find the diminutive arctic willow).

Family BETULACEAE

Like the Salicaceae, plants in this family have male and female flowers on separate structures called catkins, but the plants themselves are monoecious (both sexes on the same plant).  Two genera – Alnus and Betula – occur in the basin, each represented by one species.

Mountain alder (Alnus incana ssp. tenuifolia)

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Like the willows, mountain alder is another deciduous plant that straddles the line between tree and shrub, and as is typical of most species in these two plant families (Salicaceae and Betulaceae) the species shows a high affinity for moist sites along stream and lake margins and on seepy north- and east-facing slopes.  The largest specimens I saw, as pictured above left, were found growing on the granite sand beaches along the Rubicon Trail on the western shore of Emerald Bay in Emerald Bay State Park.  Like alders anywhere, this species is immediately recognizeable in winter due to the persistent woody cones that represent the previous year’s female catkins.  Another larger species of alder, white alder (A. rhombifolia), occurs in the Sierra Nevada, but it is not clear to me whether this species actually occurs in the Tahoe Basin proper.  Graf (1999) does not include it in his rather comprehensive treatment of Tahoe Basin plants, but Peterson & Peterson (1975) and Quinn (2006) both list it from the basin (although rare). 

Water birch (Betula occidentalis)

I did not observe this species, which Graf (1999) records from Carson Pass.  The only birch occurring in the Sierra Nevada, it is more common outside the basin proper on the eastern slopes above the burning sagebrush plains.  Like alder, separate male and female catkins are borne on the same tree; however, the female catkins of birch are solitary rather than clustered and disintegrate when ripe rather than persisting as woody cones.

Family FAGACEAE

This family contains the über diverse genus Quercus – represented in California by 20 species.  However, of the five arborescent oaks that occur in the Sierra Nevada, only one has successfully penetrated the high elevations of the Tahoe Basin. A second species of Quercus also inhabits this montane region but grows exclusively as a low shrub, and another shrub in the related genus Chrysolepis also grows here – these two latter species will be treated more fully in a future post.

Canyon live oak (Quercus chrysolepis)

The trunk was all knots and buttresses, gray like granite, and about as angular and irregular as the boulders on which it was growing—a type of steadfast, unwedgeable strength.–John Muir, The Mountains of California (1894).

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This is one of North America’s most variable oaks, exhibiting extreme variability in leaves and fruit and developing as either a tree or a shrub, depending upon the site where it grows. Slow growing and solid, it does best in sheltered locations, where it can develop an impressive, spreading crown and live a hundred years or more. On exposed slopes, it takes on a shorter, shrubbier aspect (above left) or forms dense thickets (above right).  I saw most of this species at lower elevations within the basin – along the Vikingsholm Trail in Emerald Bay State park leading down to the west shore of Emerald Bay.

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The leaves of this evergreen species are bluish green with numerous golden glandular hairs when young and becoming dull gray and smooth with age. Although there are no other arborescent oaks at this elevation with which it can be confused, I did find growing alongside it the strictly montane and shrubby huckleberry oak (Q. vaccinifolia).  The somewhat smaller, mostly entire leaves were the only indication it was not merely a shrub form of canyon live oak, and further study revealed that the two species can be distinguished by the presence of multiradiate glandular hairs on both leaf surfaces of canyon live oak.  These two species are closely related (both are in the Protobalanus – or “golden oak” – section of the genus), and widespread hybridization has apparently been documented in this part of the Sierra Nevada where the two species’ distributions overlap (Nixon 2002).

Family ROSACEAE

This large family of dioecious plants with usually pentamerous radial flowers is represented in the Tahoe Basin by nearly three dozen mostly perennial shrubs.  Six of these species, representing the genera Amelanchier, Cercocarpus, Prunus and Sorbus, sometimes develop a tree form.

Cherry (Prunus sp.)

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Two species of Prunus – bitter cherry (P. emarginata) and western chokecherry (P. virginiana var. demissa) – occur in the Tahoe Basin, both growing as either shrubs or small trees.  I cannot say for sure which species is represented in these photographs (taken on the slopes above Emerald Bay at Emerald Bay State Park), as the two species are best distinguished by subtle differences in their flowers and foliage.  Bitter cherry is apparently common in the Tahoe Basin and has bark that is smooth and dark brown, while chokecherry is more of a foothill species that is uncommon on the western shore (where these photos were taken) and has more grayish brown and somewhat scaly bark.  I can go either way with bark color based on these photos, so I’ll forgo an ID for the time being and seek to follow up during my next visit.  A third species of Prunus, the strictly shrubby desert peach (P. andersonii), formerly occurred at low elevations around the south shore, but it is now considered to be extirpated from the basin.

Mountain ash (Sorbus californica)

While hiking the Rubicon Trail in Emerald Bay State Park, I spotted a single, small tree with distinctive, large winter buds that reminded me immediately of the ornamental species mountain ash (Sorbus aucuparia) from my former days as a nursery inspector.  This thought seemed to be confirmed when I found a senesced but still attached leaf, pinnately compound with nine ovate, toothed leaflets.  However, my pocket copy of Native Trees of the Sierra Nevada (Peterson & Peterson 1975) included no species of Sorbus, and I concluded it must be something else.  This lone tree was located in deep shade within the white fir forest near the western shore of Emerald Bay, so I opted to find another tree in better lit conditions for taking photos – unfortunately, no other trees of this species were found.  Once I got back home, I was happy to find Sorbus californica listed in my just purchased copy of Graf (1999).  This species has attractive white flowers in small panicles during the summer that give rise to bright red berries during fall and is apparently common in mid- to higher-elevation riparian communities around the lake.

Serviceberry (Amelanchier spp.)
Curl-leaf mountain mahogany (Cercocarpus ledifolius)

I did not locate either of the two species of serviceberry that occur in the Tahoe Basin, the common serviceberry (Amelanchier utahensis) and the more localized glabrous serviceberry (A. alnifolia var. pumila).  Being highly familiar with our eastern species, A. arborea (just recently finished flowering), I suspect either of these species would be readily recognized, even in winter, by their smooth, silvery-gray bark and shrubby, small-tree form.  I also did not see curl-leaf mountain mahogany (Cercocarpus ledifolius), another species that barely qualifies as a small tree.  It is apparently more at home on the dry eastern flank of the Sierra Nevada but can be found within the basin proper sporadically in the southwest and along the southeastern lake shore and more commonly on dry slopes in the far north and south of the basin.  I have collected a number of woodboring beetles from mountain mahogany across the southwestern U.S. from the mountains of southern California to the Chisos Mountains of Texas.

Family ACERACEAE

The single North American genus, Acer, is represented in California by four species, three of which occur in the Sierra Nevada but only one occurring in the Tahoe Basin.  Plants in this family are closely related to the Hippocastanaceae, represented in the Sierra Nevada foothills by California buckeye (Aesculus californica).

Mountain maple (Acer glabrum var. torreyi)

As with mountain ash, I found a single small tree representing this species near the west shore of Emerald Bay while hiking the Rubicon Trail.  Despite lacking foliage, I recognized it immediately as a maple by its opposite, scaly buds.  Also like mountain ash, I assumed I would see more after finding the first one and thus didn’t photograph this particular tree growing in deep shade.  That’ll teach me.  This species sometimes grows as a multi-stemmed shrub in moist situations, and even when assuming tree form, as did the one I saw, it is at best a small tree with a maximum height of only around 15′.  With fall foliage in varying shades of pink to red, it must rather nicely compliment the blazing yellow cloak of the quaking aspen during September and October.  Tahoe Basin individuals are placed in var. torreyi due to their bright reddish twigs, while those on the eastern slope of the Sierra Nevada exhibit gray twigs and are placed in var. diffusum.

This concludes my “Trees of Lake Tahoe” series – at least until next year when I hope to locate some of the remaining species I did not find during this year’s visit.  However, I do have one more “flora of Lake Tahoe” post in preparation covering some of the many woody shrubs that occur within the basin.

REFERENCES:

Arno, S. F. 1973. Discovering Sierra Trees. Yosemite Association, Yosemite National Park, California, 89 pp.

Graf, M. 1999. Plants of the Tahoe Basin. Flowering Plants, Trees, and Ferns. A Photographic Guide. California Native Plant Society Press, Berkeley, 308 pp.

Muir, J. 1894. The Mountains of California. The Century Co., New York, xiii+381 pp.

Muir, J.  1918. Steep Trails. Houghton, Mifflin, Boston, ix+390 pp.

Nixon, K. C. 2002. The oak (Quercus) biodiversity of California and adjacent regions. USDA Forest Service General Technical Report PSW-GTR-184, 20 pp.

Peterson, P. V., and P. V. Peterson, Jr. 1975. Native Trees of the Sierra Nevada. University of California Press, Berkeley, 147 pp.

Quinn, C.  2006.  A Nature Guide to the Southwest Tahoe Basin: Including Desolation Wilderness and Fallen Leaf Lake: Trees, Shrubs, Ferns, Flowers, Birds, Amphibians, Reptiles, Mammals, and Fishes Inhabiting the Sierra Nevada Watershed Southwest of Lake Tahoe, California.  CraneDance Publications, Eugene, Oregon, 232 pp. 

Copyright © Ted C. MacRae 2009

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Glades of Jefferson County

We stood a moment to contemplate the sublime and beautiful scene before us, which was such an assembly of rocks and water—of hill and valley—of verdant woods and naked peaks—of native fertility and barren magnificence… – Henry Rowe Schoolcraft, 1818-1819

In the Ozark Border south of St. Louis, a series of natural openings punctuate the dry, rocky forests of Jefferson County. Commonly called “glades” or “cedar glades,” these islands of prairie in a sea of forest are home to plants and animals more commonly associated with the Great Plains region further to the west. Extending in a narrow arc from central Jefferson County east and south into northern Ste. Genevieve County, these glades occur most commonly on south and southwest-facing slopes below forested ridges and are characterized by thin soils and exposed dolomite bedrock of Ordovician age. Glades are, in fact, a common natural feature throughout much of the Ozark Highlands, an extraordinary plateau where the great eastern deciduous forest begins to yield to the western grasslands. A much more extensive system of dolomite glades occurs in the White River Hills of southwest Missouri, where they often extend up steep slopes and over the tops of knobs to form what Schoolcraft called “naked peaks” and are now called “balds” (and spawning the “Baldknobbers” of Branson fame). Additional glade complexes occur throughout the Ozark Highlands on different rock substrates – igneous glades abound in the St. Francois Mountains, sandstone glades dot the Lamotte landscape in Ste. Genevieve County and the northern and western Ozarks, limestone glades can be found in the northern Ozarks near Danville and Lake of the Ozarks, and chert glades occur in extreme southwest Missouri. These different glade systems share a common feature – shallow soils where tree establishment is limited due to summer moisture stress. They differ vegetationally, however, due to differences in hydrology and soil chemistry as a result of their different substrates. Floristically, dolomite glades exhibit a high degree of diversity relative to other glade types.

The term “glade” is derived from the Old English “glad,” meaning a shining place – perhaps the early settlers found their open landscapes a welcome respite after emerging from the confining vastness of the eastern deciduous forest. Whatever the meaning, the glades of Jefferson County hold a special place in my heart, for I “grew up,” entomologically speaking, in those glades. As a young entomologist, fresh out of school, I spent many a day scrambling through the glades and surrounding woodlands. It was here where my interest in beetles, especially woodboring beetles, was born and later grew into a passion. For eight years I visited these glades often – attracted by the extraordinary diversity of insects living within the glades and congregating around its edges. My earliest buprestid and cerambycid papers contain numerous records from “Victoria Glades” and “Valley View Glades” – the two best-preserved examples of the glades that once occurred extensively throughout the area (more on this later). My visits to these glades ended in 1990 when I moved to California, and although I moved back to the St. Louis area in 1995, the focus of my beetle research has more often taken me to places outside of Missouri. It had, in fact, been some 10 years since my last visit to these glades until last week, when I was able to once again spend some time in them.

Ozark glades differ from the true cedar glades of the southeastern U.S. in that they are not a climax habitat – they depend upon periodic fires to prevent succession to forest. Some recent authors have suggested the term “xeric dolomite/limestone prairie” be used to distinguish the fire-dependent glades of the Ozarks from the edaphic climax cedar glades of the southeast (Baskin & Baskin 2000, Baskin et al. 2007). Fires have been largely suppressed throughout Missouri since European settlement, leading to encroachment upon the glades by eastern red-cedar (Juniperus virginiana). Pure stands of red-cedar have developed on many former glades, crowding out the herbaceous plants that depend upon full sun and leading to soil formation that supports further encroachment by additional woody plant species such as post oak (Quercus stellata), blackjack oak (Q. marilandica), flowering dogwood (Cornus florida), and fragrant sumac (Rhus aromatica) from the surrounding woodlands. Fire has returned to many of the Ozark glades situated on lands owned or managed by state and federal agencies such as the Missouri Department of Conservation, Missouri Department of Natural Resources, and U.S. Forest Service, as well as private conservation-minded organizations such as The Nature Conservancy. These agencies have begun adopting cedar removal and fire management techniques to bring back the pre-settlement look and diversity of the Ozark Glades. This is particularly true at Victoria Glades and Valley View Glades, the two largest and most pristine examples of the Jefferson County dolomite glade complex. Fires have been used to kill small red-cedars in the glades, as well as rejuvenate their herbaceous plant communities. Larger red-cedar trees are not killed outright by fire and must be removed by chainsaws. This above distant view of the TNC parcel at Victoria Glades shows many such burned red-cedars. The glades themselves are not the only habitat to benefit from this aggressive management – when I was doing my fieldwork here in the 1980’s the surrounding woodlands were a closed post oak forest bordered by fragrant sumac and with little or no understory in the interior. The photo at right now shows an open savanna with a rich understory of not only sumac and other shrubs, but also many herbaceous plants as well such as black-eyed susan (Rudbeckia hirta) and American feverfew (Parthenium integrifolium). Such open woodland more closely resembles what Schoolcraft saw across much of the Ozarks during his journey almost two centuries ago.

Victoria and Valley View Glades are dominated by little bluestem (Schizachyrium scoparium), Indian grass (Sorghastrum nutans), big bluestem (Andropogon gerardii) and prairie dropseed (Sporobolus heterolepis). A smaller but highly charismatic non-grass flora is also found on the glades – species such as Missouri evening primrose (Oenethera macrocarpa) (left), pale purple coneflower (Echinacea simulata) (pictured above and below), and prairie dock (Silphium terebinthinaceum) not only add beautiful color but also support both vertebrate and invertebrate wildlife. The Fremont’s leather flower (Clematis fremontii) is a true endemic, occurring only in this part of Missouri and entirely dependent upon these glades for its survival. Less well studied is the vast insect fauna associated with the glades. It is here where I first discovered the occurrence of Acmaeodera neglecta in Missouri. This small jewel beetle is similar to the broadly occurring A. tubulus but at the time was known only from Texas and surrounding states. In collecting what I thought were adults of A. tubulus on various flowers in the glades, I noticed that some of them were less shining, more strongly punctate, and exhibited elytral patterning that was often coalesced into longitudinal “C-shaped” markings rather than the scattered small spots typical of A. tubulus. These proved to be A. neglecta, which I have since found on many glade habitats throughout the Ozark Highlands. Both species can be seen in this photo feeding on a flower of hairy wild petunia (Ruellia humilis) – the lower individual is A. neglecta, while the upper individual and two inside the flower are A. tubulus. Another interesting insect-plant association I discovered at these glades was the strikingly beautiful Dicerca pugionata – another species of jewel beetle – and its host plant ninebark (Physocarpus opulifolius). Only a single Missouri occurrence had been reported for D. pugionata, despite the common occurrence of its host plant along rocky streams and rivers throughout the Ozark Highlands. This plant also grows at Victoria and Valley View Glades along the intermittent streams that drain the glades and in the moist toeslopes along the lower edges of the glades where water that has percolated through the rocks and down the slopes is forced to the surface by an impermeable layer of bedrock. Unlike the tall, robust, lush plants that can be found in more optimal streamside habitats with good moisture availability, the ninebark plants of Victoria and Valley View Glades are small and scraggly, usually with some dieback that results from suboptimal growing conditions. I surmise these plants have reduced capabilities for fending off attacks by insects, including D. pugionata, and as a result a healthy population of the insect thrives at these glades. Some might be inclined to call this beetle a pest, threatening the health of one of the glade’s plants. In reality, the insect finds refuge in these glades – unable to effectively colonize the vast reserves of healthy plants that grow along streams throughout the rest of the Ozarks, it strikes a tenuous balance with plants that are themselves on the edge of survival.

Despite the success in moving Victoria and Valley View Glades closer to their pre-settlement character, the integrity of these areas continues to be challenged. Poachers take anything of real or perceived value, and ATV enthusiasts view the open spaces as nothing more than tarmac. Pale purple coneflower occurs abundantly on these Jefferson County glades (but sparingly in other habitats – primarily rocky roadsides), where they provide a stunning floral display during June and sustain innumerable insect pollinators. Plants in the genus Echinacea also have perceived medicinal value, as herbalists believe their roots contain an effective blood purifier and antibiotic. There are no conclusive human clinical trials to date that fully substantiate this purported immune stimulating effect (McKeown 1999). Nevertheless, demand for herbal use has skyrocketed in recent decades, prompting widespread illegal harvesting of several coneflower species throughout their collective range across the Great Plains and Ozark Highlands. I witnessed massive removals of this plant from both Victoria and Valley View Glades during the 1980’s, but the pictures I took this year suggest that such illegal harvests have been suppressed and that the populations at both sites are recovering nicely.

The same cannot be said for the practice of rock flipping. This was a problem I witnessed back in the 1980’s, and I saw fresh evidence of its continued occurrence at both sites. The thin soils and sloping terrain leave successive layers of dolomite bedrock exposed, the edges of which shatter from repeated freeze-thaw cycles to create rows of loose, flat rocks along the bedrock strata. Lizards, snakes, tarantulas, and scorpions find refuge under these loose rocks, only to be ripped from their homes by flippers and transferred to a dark, cold terrarium to endure a slow, lingering death. As if poaching the glade’s fauna and watching them slowly die isn’t bad enough, the flippers add insult to injury by not even bothering to replace the rock in its original position after stealing its inhabitant, amounting to habitat destruction three times greater than the area of the rock itself. Firstly, the habitat under the rock is destroyed by sudden exposure of the diverse and formerly sheltered microfauna to deadly sunlight. Next, the habitat onto which the rock is flipped is also destroyed, as the plants growing there begin a slow, smothering death. Lastly, the upper surface of the rock, sometimes colonized by mosses and lichens that might have required decades or longer to grow, usually ends up against the ground – its white, sterile underside becoming the new upper surface. Rock flipper scars take years to heal, and nearly all of the flat, loose rocks seen in the more accessible areas of the glades exhibit scars of varying ages next to them. If a scar is fresh (first photo), I generally return to the rock to its original position – the former inhabitants cannot be brought back, but at least the original habitats are saved and can recover quickly. However, if a scar is too old (2nd photo) it is best to leave the rock in its new position – replacing it only prolongs the time required for recovery.

Even more damaging is ATV use. Herbaceous plants and thin soils are no match for the aggressive tread of ATV tires, and it doesn’t take too many passes over an area before the delicate plants are killed and loose soils ripped apart. I witnessed this become a big problem particularly on Victoria Glades during the 1980’s – actually finding myself once in a face-to-face confrontation with an ATV’er. Fortunately, he turned tail and ran, and it appears (for now) that such abuses have stopped, as I saw no evidence of more recent tracks during this visit. But the scars of those tracks laid down more than two decades ago still remain painfully visible. I expect several more decades will pass before they are healed completely.

My return to Victoria and Valley View Glades was a homecoming of sorts, and I was genuinely pleased to see the progress that has been made in managing these areas while revisiting the sites where my love affair with beetles was first kindled. Sadly, however, the larger glade complex of Jefferson County continues to deteriorate. Restoration acreage aside, red-cedar encroachment continues unabated on many of the remaining glade parcels – large and small – that dot the south and southwest facing slopes in this area. It has been conservatively estimated that as much as 70% of the original high quality glades in Missouri are now covered in red-cedar. Many of these are privately held – their owners either do not recognize their ecological significance or are loathe to set fire to them. An example can be seen in the picture here – this small parcel is part of the Victoria Glades complex but lies on private land in red-cedar choked contrast to the Nature Conservancy parcel immediately to the south. Small numbers of herbaceous plants persist here, but without intervention by fire or chainsaw their numbers will continue to dwindle and the glade will die. Aside from the loss of these glades, the continuing reduction of glade habitat complicates management options for preserved glades as well. Many glade associated invertebrates are “fire-sensitive” – i.e., they overwinter in the duff and leaf litter above the soil and are thus vulnerable to spring or fall fires. While these fires are profoundly useful for invigorating the herbaceous flora, they can lead to local extirpation of fire-sensitive invertebrate species within the burn area. Recolonization normally occurs quickly from unburned glades in proximity to the burned areas but can be hampered if source habitat exists as small, highly-fragmented remnants separated by extensive tracts of hostile environment. Grazing also continues to threaten existing remnants in the Jefferson County complex. Grazing rates are higher now than ever before, with greater negative impact due to the use of fencing that prevents grazers from moving to “greener pastures”. Over-grazing eliminates native vegetation through constant depletion of nutrient reserves and disturbance of the delicate soil structure, leading to invasion and establishment of undesirable plant species. Eventually, the glade becomes unproductive for pasture and is abandoned – coupled with fire suppression this leads to rapid woody encroachment. It is truly depressing to drive through Jefferson County and recognize these cedar-choked glades for what they were, able to do nothing but watch in dismay as yet another aspect of Missouri’s natural heritage gradually disappears. The continued loss of these remnant glades makes careful use of fire management on Victoria and Valley View Glades all the more critical – ensuring that a patchwork of unburned, lightly burned, and more heavily burned areas exists at a given time will be critical for preventing invertebrate extirpations within these managed areas.

I close by sharing with you a few more of the many photographs I took during this visit – stiff tickseed (Coreopsis palmata), three-toed box turtle (Terrapene carolina triunguis), climbing milkweed (Matelea decipiens – see the excellent post about this plant on Ozark Highlands of Missouri), downy phlox (Phlox pilosa), green milkweed (Asclepias viridiflora), and a “deerly” departed native browser.

Pipestone National Monument

Grandson, do not expect to accomplish much in this lifetime, for no one shares your vision… – The Oracle


Wednesday was my birthday, and it has been my custom for many years now to take the day off and go hiking/bugging somewhere. Coming as it does in early spring, it is usually the first real bug collecting trip of the year. This year, however, I was roped into a short business trip to visit a USDA lab in Brookings, South Dakota, so tradition would have to take a back seat. My visit at the lab ended early, though, and my flight back home from Sioux Falls didn’t leave until that evening, so I studied the map to look for any possible nearby points of interest in this landscape that has, for the most part, been unforgivingly converted to fields of corn, soybean, and wheat. I quickly noted a place called Pipestone National Monument just over the border into Minnesota. I love stopping at national monuments while traveling – they usually have some significant historical or geological interest, and their typically (though not always) small size means one can fully explore the area in a relatively short time. I did not know or had never heard of this place, but what I found was a charming little jewel tucked within a remnant of tallgrass prairie. At this far northern latitude, spring is still in its earliest of states. Few insects would be seen, but nevertheless I felt thankful for the chance to spend time outdoors and in a place of beauty where I could reflect on the years gone by and those (hopefully) still to come.

The area is named for a thin layer of catlinite – pipestone – exposed in this small area that has been quarried for centuries by Native Americans for carving into pipes (both war and peace). Quarrying within the monument continues to this day, with permission to do so reserved by law only to registered Native Americans. The area is identified as a sacred site associated with Native American spiritual beliefs and is preserved as a significant cultural and ethnographic landscape. Of particular interest to me was the site’s distinct hydrologic/geologic landscape and the native tallgrass prairie associated with it. A short ¾-mile trail loops through the area, providing a diverse glimpse of the area’s unique features. Pipestone may have provided the area’s namesake, but a narrow exposure of Sioux quartzite is the area’s most prominent geologic feature. Sioux quartzite is derived from billion and a half year-old layers of sand/silt sediments deposited thickly on the floors of ancient, Precambrian seas and compressed over the vastness of time into a hard, reddish metamorphic rock. Normally covered in this area by glacial till, the layers at this site are tilted upward 5–10 degrees towards the west and break through the surface to form a jagged, mile-long west-facing escarpment 23-30 feet high. Underneath the quartzite is the pipestone, a thin layer of metamorphosed shale. This fine-grained rock is derived from clay deposits, thus it is much softer and redder than the harder-than-steel quartzite. Pipestone Creek bisects the escarpment, giving rise to the lovely Winnewissa Falls, flowing over the escarpment and running down to a small, natural empoundment (Hiawatha Lake) before continuing its journey back into the glacial till and tallgrass prairie (for anybody surprised that there should be “falls” in this part of the country, it is interesting to note that nearby Sioux Falls is named after a grander example of of such flowing over quartzite exposures in its downtown).

Precious little remains of the expansive tallgrass prairie that once extended from horizon to horizon in this area. A few small parcels managed to escape the plow, but even in those tiny remnants dramatic alterations in plant communities have occurred due to fire suppression and the introduction of more than 70 non-native plant species. Prescribed burning programs are now being used at the Monument to restore the prairie’s native plant composition and appearance. Looking out over the tallgrass prairie remnants above and below the quartzite escarpment, it I was tempted to visualize circles of teepees on the higher ground away from the quarries (all Native American tribes worshipped this site and would never camp directly within it), with herds of American bison dotting the landscape in the distance. Contrasting with the openness of the prairie, the escarpment itself is densely studded with trees – American elm (Ulmus americana) along the top edge, and bur oak (Quercus macrocarpa) in the escarpment itself. Unlike the large, sometimes towering examples of their kind found further to the east, the trees here are dwarfed and spreading, almost gnarled. Below the escarpment, woodland quickly gives way to pure stands of smooth sumac (Rhus glabra) and choke cherry (Prunus sp.), which just as quickly yield to the surrounding sea of prairie. Along Pipestone Creek below the escarpment, lower layers of exposed quartzite provide nooks and crannys where enough moisture collects to support the growth of green ash (Fraxinus pennsylvanica) trees, until glacial till once again covers the quartzite, and riparian woodland yields to grasses and forbes. It’s not hard to imagine why this became a special place to the Native Americans, even before they discovered the pipestone that was to become so important to their culture.

The pipestone quarries are located a short distance to the west of the escarpment – where the hard quartzite layer is thin enough to break through – and, thus, have had little impact on altering the physical appearance of the escarpment itself. Winnewissa Falls (meaning “Jealous Maiden” in the Dakota language), lies at the center of the escarpment, providing a stunning centerpiece. Despite its beauty, it is but a shadow of what it was before early settlers in the area blasted away the top 18 feet of the ledge to create a reservoir for drinking water. A century of weathering and recolonization by lichens and mosses have softened the scars on the rocks, leaving little to indicate that such a dramatic alteration took place. However, standing in front of the falls, finding that “zone” where the temperature suddenly drops and cool wet mist blows on the face, and thinking about the significance of this place to the Native American tribes who held it so sacred, I was left feeling bewildered at how such drastic measures could have been contemplated for so beautiful a place.

In addition to the falls, nature has created some striking sculptures in the rock. “Old Stone Face” can hardly be mistaken for anything else – despite its human likeness, it was created entirely by natural forces. “The Oracle” is another naturally-formed human likeness found (though not as easily as Old Stone Face) in the outlines of the rocks. Tribal Shamans (Medicine Men) believed it served as a guardian of the valley and that voices issued from it’s cold stone lips. I stared for awhile and strained to listen, trying to imagine what words it might have spoken. At first, it seemed as if all was silent. Then I noticed the sound of the wind rolling over the prairie and twirling through the gnarled oaks. I heard the falls in the distance. I heard birds in the midst of frantic early-spring songs. I thought perhaps these might be the voices that guided the Shamans – spoken so loudly, yet so easily unheard.

The first U.S. government expedition to the quarry occurred in 1838 with Joseph Nicollet, a French scientist who was sent to map the upper Mississippi country. He and the members of his expedition carved their names in the rocks atop the escarpment, as did many of the early pioneers that first settled in the area. In studying the surface of these rocks, I couldn’t help but notice the incredible diversity of lichens to be found. Around 75 species are known from the area, and as shown in the photos I share below they come in a fantastic array of forms and colors. Lichens are primary colonizers of rock surfaces, able to do so as a result of their nutritional autonomy. Lichens are merely fungi that have evolved a specialised mode of nutrition: symbiosis with photosynthetic microalgae or cyanobacteria. Often, the algal component is capable of fixing nitrogen from the atmosphere, while the fungal organism attacks the rock with organic acids to release minerals. This is the basis of soil formation. Over time, enough soil accumulates in small depressions to allow mosses to colonize the rock surface. As successive generations of moss grow and die, more and more organic material accumulates on the rock surface, eventually supporting the growth of vascular plants (which extract nitrogen from the soil, rather than from atmospheric sources). These cycles of growth and death act in concert with the forces of erosion to ultimately convert barren rock to tallgrass prairie, hardwood forest, or other climax habitat. Mind you, this is an extraordinarily slow process – it can take a full century for a lichen to grow one inch! As I looked at the abundance and diversity of lichens on the rock surfaces, I tried to visualize the breadth of time encompassed by what was before me and quickly became lost in eternity.

While the trail that loops through the area is less than a mile in length, it took me an hour and a half to complete it. What started out as a few hours to kill ended as a hurried rush through the museum and interpretive center, trying to cram a few last morsels of knowledge into my head in those final moments before I would have to submit to the drive back to Sioux Falls. As I left the area, I noticed these oddly out-of-place boulders known as “The Three Maidens.”
Native Americans believe that these boulders shelter the spirits of maidens who demand offerings before permitting them to quarry the pipestone. Science tells us that the boulders are composed of granite and were likely carried here by glaciers during the past 1 million to 10,000 years ago. Originally a single boulder some 50 feet in diameter, repeated freezing and thawing over the millenia since it was dropped here have split the boulder into the several pieces seen here. Perhaps only The Oracle knows which is true.

For a more detailed, yet highly readable account of the geology of this area, please consult Minnesota Geology, Field Trip, Summer 2000 and Other MN DNR Workshops, by Arlyn DeBruyckere.

Muir Woods National Monument

This is the best tree-lovers monument that could possibly be found in all the forests of the world. – John Muir

Coastal redwood (Sequoia sempervirens) is the tallest type of tree in the world, with maximum recorded heights approaching 380 feet. This majestic conifer grows only along the Pacific Coast in a narrow strip from Monterey to Oregon. Most of the estimated 2 million acres of original redwood forest are now gone — victims of the saw! One of the small groves that managed to escape this fate due to its relative inaccessibility grows along Redwood Creek and adjacent slopes in what is now Muir Woods National Monument. At heights approaching 260 feet, the redwoods growing here are not the tallest to be found; however, their proximity to San Francisco (just 15 miles from the Golden Gate Bridge) makes them the most heavily viewed examples of this ancient tree. Lynne and I visited Muir Woods a few times in the 90’s after moving to Sacramento — today (3/20) was our first visit since then, and the first ever for Mollie and Madison. In addition to getting to see these marvelous trees once again, we were also treated to a spectacular display of spring wildflowers.

We began our hike on the main paved trail. This is where most visitors confine themselves during a visit to this place, so the picture here documents a rare sight — no people! I apologize for its lack of focus, a consequence of the limitations of my little point-and-shoot camera in the limited amount of light that makes it through these towering trees during late afternoon.

Standing beneath one of these trees and looking up is a lesson in insignificance — the feeling one gets looking straight up the trunk of one of these giants cannot be adequately captured on film (er… microchip).

We quickly tired of the crowds and decided to hike up the Ocean View Trail, which climbs quite steeply up the east side of the valley. This marvelous trail was nearly devoid of people, and we found ourselves winding through thick, dark, cool forest with numerous side ravines. The lower elevations of the trail were dominated by redwood trees and a spectacular array of spring wildflowers. Among the most common was California toothwort (Cardamine  californica [=Dentaria californica]), a member of the mustard family (Brassicaceae). I noticed that the leaves at the base of the plant were broad and oval, while those arising from the flower stalk were slender and lanceolate, often divided into 3 leaflets.

Wake robins (genus Trillium), belonging to the lily family (Liliaceae, sometimes separated into the lily-of-the-valley family, Convallariaceae), are among my favorite wildflowers. We soon noticed Western wake robin (Trillium ovatum) growing commonly in shaded areas along the trail. We were also seeing some purple-flowered wake robins — at first I thought they were a different species, but it soon became apparent that these were older Western wake robin flowers, which change color from white to purple as they age.

A little further up the trail we began encountering small patches of Mountain iris (Iris douglasiana, family Iridaceae). Flower color for this native species ranges from cream-white to lavender, but all of the flowers we saw were of the white variety.

We saw this fat Solomon’s seal (Maianthemum racemosum ssp. amplexicaule [=Smilacina racemosa var. amplexicaulis]) growing in one of the cool, moist, side ravines. This is another member of the Liliaceae (sometimes separated into the Convallariaceae). The large, oval leaves clasping around the distinct, unbranched stem were almost as attractive as the flowers, which apparently give rise to bright scarlet berries in the summer.

In the middle elevations the redwood forest transitioned to drier oak woodland containing a mixture of Douglas-fir (Pseudotsuga menziesii), Pacific madrone (Arbutus menziesii), bigleaf maple (Acer macrophyllum), and tan oak (Lithocarpus densiflorus). Some of the Douglas-firs were enormous.


Indian warrior (Pedicularis densiflora) is a member of the figwort family (Scrophulariaceae, sometimes separated into the Orobanchaceae). This plant, with its striking bright red flowers and finely divided, fern-like leaves, is a facultative parasite on the roots of other plants. Apparently, the genus name refers to an old superstition that sheep could become infested with lice if they ate this plant.


The juncture of the Ocean View Trail with the Lost Trail was closed, so we backtracked down the 1+ miles back to the main paved trail. By now it was fairly late in the afternoon, and the crowds had thinned considerably. Having gotten lots of good views of the giant trees, we began turning our attention downwards to the smaller understory flora. Ferns, of course, are a dominant component of this understory, especially along Redwood Creek. This large specimen may represent Western sword fern (Polystichum munitum) (family Dryopteridaceae), which can apparently be distinguished by small hilt-like projections from the base of the pinnae (leaflets), but I couldn’t get close enough to see for sure.


Abundant on the ground in the valley was redwood sorrell (Oxalis oregana), a member of the family Oxalidaceae. In places this plant covered the ground in thick carpets.


Among the more interesting plants we saw in the valley was California fetid adder’s tongue (Scoliopus bigelovii), yet another member of the Liliaceae or Convallariaceae. I wasn’t sure what this plant was at first, despite its highly distinctive, glossy, mottled foliage. We were too late to see the blooms, which apparently have a fetid odor to attract flies for pollination, but did find the maturing pods on their slender, drooping stems.


Close to the creek’s edge we saw this colony of horsetails (Equisetum sp.), primitive plants in the family Equisetaceae. Members of this group belong to one of the most ancient lineages of vascular plants, dating back to the Devonian period (416-359 million years ago). Their Paleozoic ancestors (Calamitaceae and Archaeocalamitaceae) were giants, reaching heights of 50 ft or more, and were major components of the Carboniferous swamplands. Along with lycopod trees (Lepidodendrales), they were important contributors to coal formation and, like the lycopods, became extinct by the mid-Permian (~270 million years ago). The genus Equisetum represents the only surviving descendants of this lineage. Unlike their extinct progenitors, these small, herbaceous plants rarely exceed 4 ft in height; however, they share many of the same characters such as articulate stems with microphylls arranged in whorls. Recent phylogenetic studies, using both molecular and morphological characters, suggest that horsetails, together with ferns, form a clade representing one of the three major lineages of vascular plants (Pryer et al. 2001).


Nearby we saw a patch of Giant wake robin (Trillium chloropetalum) in flower. These were taller than the California wake robins we saw on the slopes of the Ocean View Trail but similarly characterized by a whorl of 3 leaves and flowers composed of 3 erect petals. Mature flowers darken to a deep red purple, so it seems these plants had just begun flowering. Muir Woods appears to be a good place for observing a diversity of Convallariaceae!


Also along Redwood Creek we found this bigleaf maple (Acer macrophyllum) in full bloom. As its specific epithet suggests, this maple has the largest leaves of any member of the genus — in this example the newly-expanded leaves were distinctly purplish. The picture below shows the greenish-yellow flowers (petals inconspicuous) produced on long, pendulous racemes.


Interpretive signs along the paved main trail pointed out a redwood “family group,” formed by sprouts growing from the base of a larger tree. Eventually, the central “mother” tree died and decayed away, leaving a ring of offspring that mature into an enormous, characteristic circle of trees. This apparently also happens with other types of trees, though on a smaller scale, as demonstrated in this picture of an oak (Quercus sp.) family group.


As the day drew to a close we found ourselves back in the parking lot, where this California icon, a clump of Coast live oak (Quercus agrifolia), was spreading its wide, majestic crown from multiple, twisted trunks and gnarled branches.


Much too soon, it was time to leave this beautiful valley, but before heading back to Sacramento we stopped to take one last look down towards the valley and out to the Pacific Ocean from the Panoramic Highway.

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 😉


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°F, 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.