Solomon Gamboa Pioneer Landscapes LLC Pionersprouts.com

Solomon Gamboa
Pioneer Landscapes LLC Pionersprouts.com [email protected]
Caesar Creek-Forests from the Soils Workshop-Recap
Ceasar Creek Gorge Trail, located at the tailwater parking lot
We started with a quick discussion on how ancient valleys carved by rivers and their
tributaries much older than the last glacial period ended (17,000 years ago) have
worn away our Ordovician limestone/shale formations creating slopes too steep for
much of the glacial deposits to stick. These slope conditions preserve our residuum
soil, soil formed in place from weathered bedrock as opposed to soil transported by
glaciers, water, or wind. Due to the shallowness of the soil on these valley hillsides,
likely due to constant natural erosion of soil on slopes so steep, the bedrock is very
much near the surface. We could notice limestone, which breaks down much slower
than our gray shale, laid throughout the surface of the soil, and on upturned trees
you could see much limestone pulled up by the roots. This shallow rocky soil
residuum soil supported circumneutral (6.5PH-7.5Ph) adapted species, you could
also call these our alkaline tolerant species. These were Bur Oak, Chinquapin Oak,
Shumard Oak, Blue Ash, Shellbark Hickory (leaflet of 7 with shaggy bark), and Ohio
Buckeye. PH Generalist such as Red Oak, Bitternut Hickory, Sweet Pignut, Sugar
Maple, Black Maple, and understory species of Hornbeam, Blackhaw viburnum, and
spicebush were present throughout. IF you fallow the rivers of this water shed and
their tributaries and you locate the valley hillsides that run parallel, you can find
different variations but very consistent formations of this above forest type. I call it
our Upland Alkaline Forest Variation, and have written about it extensively on this
blog post. These soils we walked were Eden-Fairmount with an average depth of
12”-36” before hitting either lithic or paralithic bedrock. lihtic in this case inferring
that the bedrock was solid and impenetrable by roots, paralithic inferring less solid
and penetrable by roots.
As we reached the high, flat elevation we initially walked through some acidic
poorly drained glacial till that was in early successional stage of what would be the
Pin Oak-Red Maple-Green Ash forest type. We saw how the high water table on the
acidic soil allowed for saturated soil tolerant specie to thrive, different from our
local flood plain species which dominate in intermittently saturated, alkaline soils.
The water table as we took notice, allowed for the habitat creation of the upland
ponds as one only had to dig a foot or so down to reach water. This poor drainage
was created by the glaciers depositing soils in a flat manner filling drainage ways
developed before the last ice age. So we notice the that creeks/dry runs on top of the
hill were cutting through deep soil deposits with little to no limestone present, but
as the creeks/dry runs flowed down the shallow residuum soil hillsides it exposed
layers of limestone demonstrating the depth of the glacial deposit vs the shallow
rockiness of the residuum hillsides below. These soils were Cincinnati Silt Loams, in
the 5.1 ph range. As we progressed down the trail, we noticed how we were at a
meeting point of 3 different soil conditions, with a mix of poorly drained, and well
drained acidic glacial till on top of the hill allowing mixing of Pin Oaks (Swamp
forest species) with Red Oak and White Oak (Better drained Acidic Soil Species)
with upland alkaline soil forest variation species like Chinquapin Oak and Bur Oak.
That narrow line of great mixing was owed to being at the edge of where the glacial
deposit couldn’t stick so well to the quickly descending valley hillside leaving areas
of more so alkaline, near acidic glacially deposited soil.
Further down the trail, after talking about acidic soil indicators (black gum, Black
Oak, White Oak, and Pignut Hickory) we went out into the man-made tallgrass
prairies growing atop the spill way. Here I pointed out, due to poorly drained
hydrology, the unmowed prairie had progressed into early successional swamp
forest with Arrowwood Viburnum, Pin Oak, Sassafrass, Shagbark Hickory, Green
Ash, and Red Maple pioneering into the unmaintained areas of the prairies that
hadn’t been mowed probably in the last 8 -10 years. This demonstrated how even
after we log a forest, and change the hydrology a bit in some cases, and perhaps
even compact the soil, the prairie can provide an ideal successional habitat to the
former forest types of that soil especially in cases where there is still local genotype
mother trees still near the site. Back into the forest we saw Sweet Pignut with a
leaflet of 7, a highly palatable hickory species that acts as a generalist locally but is
more common in acidic soils, and I commented on how at the ridge of these valley
hillsides the Flowering dogowood finds some kind of light exposure niche and is
able to reproduce abundantly there.
Down the back into the valley hillsides we saw more of the upland alkaline forest
variation, chartaericzed by rock limestone shallow soil with grey clay produced by
our grey shale, and since this hillside faced west, it was stunted by not only shallow
soil, but a hot slope/aspect. This forest was mature, yet it looked very broken due to
the slow growth/inabaility for the canopy species to close the canopy leading to a
very diverse dense understory of prickly ash, and bladdernut at lower elevations,
and flowering dogwood, black haw viburnum, eastern redbud and other midstory
species like hornbeam thriving at higher elevations. This area also had an
abundance of summer forest wildflowers such as Eutrotchium purpureum the
woodland joe pye weed and Desmodium species due to the long periods in which
the canopies are broken letting sun hit the forest floor.
At the bottom of the hill we walked what I hypothesized was the old riverbed of
Caesar Creek that had changed elevation and location over time creating a rocky
bottomland of soil that due to the elevation and likely dam engineering no longer
flooded as often as it may in the past. This flat bottomland topography differed from
the high flat glacial tillplain in that it was alkaline and received water flow from the
uplands where as the high till plains only received water in the form of
precipitation. This promoted Shellbark Hickory, and a dominance of Black walnut
which is a PH generalist that thrives in higher moisture soils, but not saturated soils
also accompanied by Blue Ash, Sycamore, Box elder Maple, Black Maple, Chinquapin
Oak, and Bur Oak. The shallow rocky soil, even though at a flat elevation, still
promoted some light hitting the forest floor allowing fore specie like our Wild
bergamot to thrive in the partial shade created by large gaps in the canopy.
On the way back to the parking lot, we just got close looks at the Blue Ash, Shellbark
hickory, Chinquapin Oak, and smooth hydrangea clinging to the limestone/shale
residuum soils as they meet the river.
Use the provided spreadsheets and this recap, to help extract the lessons from the
lecture. The spreadsheets are key to remembering the different soil PH and parent
soil associations.