What do Wisconsin Oak Woodlands Look Like?

Oak woodlands and prairies are related. In a broad sense, oak woodlands are also grasslands (or graminoid-lands), often supporting rich sods of herbaceous plants set in a matrix that includes grasses and sedges (and often common wood rush). In Wisconsin both oak woodlands and oak openings are lumped together under broader savanna, but oak woodlands are deserve special attention. They are communities of dappled light filtered through oakneither dark forest nor fully exposed. They are as defined by their herbaceous vegetation as they are by their trees, but very seldom do oaks still coincide with intact, old-growth woodland sod. Are truly intact woodland sods as rare or rarer than prairie sods? Perhaps. Three very common and widespread historical factors have driven the decline of oak woodlandgrazing, fire exclusion, and forestry practices. The best remnants are found where one or more of these factors was muted various factors–access, wind blowing leaf litter clear. All too often, opportunities to restore woodlands go unrecognized in favor more open savanna types or management of closed forests. In this post my aim is to show some small fragments of oak woodland, mostly degraded but still recognizable as such. One thing to notice is that the vegetation is low and grassy, regardless of time of year. I’ll be adding to this post over time.

This remnant oak woodland at the Army Lake Boat Launch in Walworth County (the foreground is paved now) is / was truly remarkable. Located on a knoll surrounded by open water and peatland, it was likely minimally disturbed before an access was created in the 1950s. It’s possible that the topography and openness to the lake exported leaf litter that would have otherwise smothered its sod. Mesic and situated on silt loam soils, it supports huckleberry and velvet-leaf blueberry.

An image of the old growth sod of the Army Lake Woodland–a matrix of common wood rush, savanna running sedge, Pennsylvania sedge, Robin’s plantain, wood betony, yellow stargrass, and common blue-eyed grass. Other areas are co-dominated by species including bastard toadflax, forked aster, Carolina vetch, pale vetchling, New Jersey Tea, and midland shooting star.

Another bit of Army Lake Woodland sod, here full of two-flowered Cynthia, Carolina vetch, and bastard toadflax.

This is Summit Bog Island in Waukesha County, a knoll of silt loam soils surrounded by peatlands. It is moderately compositionally and structurally degraded, but unlike most areas, the understory has not yet become choked with invasive shrubs. It remains graminoid-dominated. The main issue is the slow encroachment of ironwood, black cherry, and shagbark hickory. Here too, at least some potentially smothering leaf litter is exported by wind.

A view of the sod at Summit Bog Island. Visible are velvet-leaf blueberry, Pennsylvania sedge, savanna running sedge, red vine honeysuckle, Parlin’s field cat’s-foot, shining bedstraw, and grove sandwort. Carolina vetch, pale vetchling, Maryland black snakeroot, bastard toadflax, showy goldenrod, arrow-leaved aster, and poverty oatgrass, northern hawkweed, common wood rush, rough hawkweed, and broad-leaved panic-grass, are among the other species present, but much appears suppressed here due to conspicuous severe deer browse. The “island” knoll is a hub connecting all the deer paths through the surrounding peatlands.

This oak woodland on a northwest-oriented ridgetop dolostone point in the Trempealeau County. Here Pennsylvania sedge, savanna running sedge, poverty oatgrass, and broad-leaved panic-grass are among the graminoids. Yellow pimpernel, Carolina vetch, and northern bedstraw are abundant. Woodland sunflowers are atypically benign. A more red oak-domianted north slope supports low bush honeysuckle, broad-leaved panic-grass, poke milkweed, yellow lady’s slipper, and northern bedstraw.

This Iowa County oak woodland over sandstone suffers somewhat from excessive leaf litter accumulation, but Pennsylvania sedge and Swan’s sedge are both present. Forbs include midland shooting star, northern hawkweed, rough hawkweed, hoary frostweed, stiff aster, showy goldenrod, and bastard toadflax. White oak grubs/seedlings are abundant, as they often are under a high oak canopy where the understory hasn’t become too full of brush and small trees.

Oak woodland in historically heavily grazed area at the toe of an esker in Walworth County. Nonetheless, the graminoid structure is retained and there is much white oak regeneration. Midland shooting star, alumroot, Pennsylvania sedge, Swan’s sedge, and common wood rush are present.

Woodland on south slope under white and red oak (canopy was present in 1940 as well) at another “island” woodland remnant near Army Lake in Walworth County. This island is a kame or kame-like structure and consists of rocky-domomitic till. Prominent graminoids are savanna running sedge, Leiberg’s panic-grass, Pennsylvania sedge, poverty oat grass, slender wheatgrass, and common wood rush. Large yellow false-foxglove, lead plant, bastard toadflax, showy goldenrod, sky-blue aster, shining bedstraw, northern bedstraw, kittentails, midland shooting star, Robin’s plantain, and early goldenrod are also present.

Historically heavily grazed oak woodland over sandstone in Richland County. Pennsylvania sedge, poverty oat grass, savanna running sedge, hoary frostweed, prairie pinweed, rough hawkweed, and northern hawkweed are among the remaining flora. White oak seedlings/grubs are dense.

An open portion of an “island” (thicketed areas were historically more open) between Lulu and Eagle Spring Lake in Walworth County. Carolina vetch, grove sandwort, alumroot, and broad-leaved panic-grass are among the species present.

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What Does Long-Term Bison-Grazed Prairie Look Like?

Bison-grazed pastures tend to have higher forb cover and vascular plant diversity in prairie (bison have been there now for 35 years), but what does this look like. I have some pictures from quadrats from field work at in Konza’s N2B watershed (Bison + Fire every other year) taken nine years ago. It’s worth noting that spring burning at Konza is usually conducted between late March to early May, which is mostly/usually well into the growing season there (I used to volunteer, and Baptisa australis was often flowering at burn time), and that large swathes of bison watersheds lack enough fuel to burn when fire is applied (every other year is the frequency of fire application, not actual burning).

The below photos were taken in August. I’m not going to say here whether I like what I see or not. It should be pretty obvious. These are from a reference area of “intact” prairie used for a woody removal study that is in preparation. Another grad-student colleague and I helped by collecting baseline vegetation data. The woody removal did not work in the long-term, because TNC didn’t want cut woody vegetation treated near the stream. It was simply cut and left to resprout. …and woody vegetation removed included a few open-grown chinkapin and bur oaks about 150 years old (I counted rings on the stumps), which had green dragon and wild coffee under their canopies. That’s a tangent, but sometimes the big picture in science misses some of the nuance of what is being studied.

This area is indeed forbier and more diverse than frequently burned Konza watersheds that aren’t grazed, which are over-dominated by the big warm-season grasses, because burning is late (within the growing season) and probably also due to legacies of past broad-leaf herbicide application that would have occurred for warm-season pasture management. Here, the most prominent forbs are western ragweed (Ambrosia psylostachya), Canada goldendrod (Solidago canadensis; or tall goldenrod, Solidago altissima. The former is on the Konza list and I didn’t know the difference in the early 2010s when I did this work), Baldwin’s ironweed (Vernonia baldwinii), stiff goldenrod (Solidago rigida), and hoary vervain (Verbena stricta). These were easy quadrats to do!

Konza is just one site (even if subdivided into pseudo-replicates, which are reasonable at that scale), and results, I’m sure, will vary with duration, seasonality, stocking rates, and geography.

I distinctly remember getting out of the truck in a bison watershed on my first tour of Konza before my graduate program began and being struck that this was more or less the vegetation, and I haven’t seen a case yet that struck me differently. This could be Minneopa State Park in Minnesota, for instance. Bison are appropriate at Konza and elsewhere in the western tallgrass and on the Great Plains where they were an important historical presence, but the devil is in the details of fencing them in.

This links to Konza’s bison fact sheet.

Looking into the bison enclosure at Minneopa State Park near Mankato, MN. This is also has a lot of forbs–Erigeron and Artemisia.

A few decades ago there was a debate between Konza researchers and those working on more eastern prairies about what the context of and results from Konza mean for prairie management–and simply what maintains prairie. See the Bioscience article and response. It’s worth a look.

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Botanists are NOT Ruining Prairies

Wait, what?!

More than a decade ago Prairie Ecologist asked, “Are botanists ruining prairies?” I’d met the author, worked with him to set up a portion of my dissertation research. I’d come west from Iowa in 2008 with an open mind, drawn by the larger landscape prairies in Kansas, Nebraska, and Oklahoma. If anything, Prairie Ecologist was a role model, someone who had my attention, and whose career I would have been happy to mirror.

But with all the time I spent walking prairies, between the western margins of the tallgrass and its heart in Iowa, an uneasiness crept in. Then Prairie Ecologist posed the question, and I didn’t actually find the post for a while, but after I read a few paragraphs and had to step away. I put it out of my mind.

Recently the post showed up in my Google search results, so I read the whole thing. I’m thankful to my past self for sparing me the exasperation. The post is framed as lighthearted, a prod, but it’s a hot fallacious mess that reveals a lot of underlying biases and assumptions and both caricatures and minimizes the work and dedication of the people we have to thank for the prairies we still have today.

Prairie Ecologist claims that the prevailing dogma is that high quality prairies have a lot of “conservative plants,” and that these plants are defined as being rare in most prairies and…perhaps even “fragile.” FRAGILE. What follows is a free-wheeling essay on why it might not be the best thing that the botanists are so adamant about protecting small patches for Fabergé plants.

For starters, conservative plants are defined quite differently. If you are standing in the field looking at a very conservative plant, indeed, you are probably not standing on an old slag heap or in a recently fallowed field—but much more likely a remnant natural community that Europeans haven’t screwed up with novel disturbance or exclusion of essential indigenous disturbance. Are conservative species fragile if they lose ground or disappear in response to being fenced in with livestock, turned under by the plow, bulldozed? Are we really going to call any organism fragile and ignore the course of its entire evolutionary history and biogeography up to the present? Fragile? It’d be silly. Had we succeeded in eliminating the bison, would it be fragile? If ever there was a strawman put up, setting up conservative plants as fragile is one.

Four acres of fragility.

The post goes on to say “A compass plant is usually considered to be a conservative wildflower in prairies,” and “so, a prairie filled with lots of fragile plants is considered to be a high quality prairie.” A compass plant is fragile? The same compass plants that have pushed back up along county roads after multiple rounds of grading, withstood severe droughts, fires, and deep frost to live lord knows how long? Fragile, just because they’d have died if they stood on the same side of the fence as the cattle? On initial reading I was still hoping that the author wasn’t serious. …waiting for the punchline.

The post goes on to say “a prairie filled with prairie plant species that are tough and scrappy is considered to be degraded.” In another post he derides prairies packed with conservative species as “calendar prairies.” All this while every one of those calendar prairies species still has its suite of “scrappy” species—it’s black-eyed Susans, biennial evening primroses, wedgegrass, rough dropseed, and prairie thistles in addition to those “fragile,” conservative ones. Those scrappy species are not considered conservative, because they also grow in fallow fields, along roadsides…on slagheaps. It’s wonderful that they do! But crossing paths with them doesn’t tell you that you’re standing in an in an old growth prairie. It also doesn’t tell you that you’re not standing in one. …but that would be a more difficult concept to parlay into the question of whether botanists are ruining prairies. That said, I won’t dispute that the scrappies in an old-growth prairie are pushed to the margins by the “fragile” species whose resource use efficiency and complex and mutual interactions force them to the week spots in the sod—the gopher mounds and abandoned ant hills.

Leiberg’s panic grass, a conservative species sensitive to grazing and excessive litter accumulation.

Prairie Ecologist said “we tend to think about human society in much the same way…society consists of fragile people with clean fingernails and uncalloused hands who have to hire low-society people to cook, clean, garden, and take care of their fancy cars,” and “low-society people work hard to feed themselves and their families, wear functional clothes (without designer labels)….” What fresh projection is this? So the species that don’t stand and cheer after the cattle move on to the next pasture are the rich takers? Do-nothings? A Silphium stem borer or a phlox moth might beg to differ. Look at your hands. I hope they’re calloused (mine are). Phew.

Prairie ecologist further caricatures champions of “fragile” plants, “It’s certainly understandable that people who dedicate their lives to plants would be concerned about preserving those plant species that are the most difficult to preserve.” Is there a point? Perhaps unintentional, this feels like a minimization of the work of dedicated botanists, and also stewards and ecologists that see things differently. I’m often called a botanist, though my undergraduate and graduate training gave me no formal training as such. My training was a broad biological, ecological, and statistical one. But I learned long ago that the flora is a powerful lens through which to view the world, so I’ve become a passably good field botanist that can say a lot about a place based on the plants I see. There are other lenses, sure. My first biological loves were reptiles, amphibians, and fish. It’s easier to dismiss a point of view if you can claim the competing perspective is a narrower one than yours. If the botanists were out there irrationally dedicating their lives to plants, why would it even cross their minds to assign them scores that indicate affinity to old-growth natural communities?

Prairie’s gotta earn a living. “Most grasslands in today’s landscapes have to earn their keep, and are managed in ways that tend to favor species that are tough and scrappy, rather than those that are fragile.” Well, the first third is true. We continue to force the land into our Old World ways of doing things. We value hard workers. After all, they feed the world, right?

Pieris rapae? Strong as an ox. Papaipema beeriana? Soft bean counter. Prairie Ecologist would never say that. It’s preposterous. I wouldn’t either.

I will concede that in the world we live in, the only way to get more surrogate grassland on the landscape is if it somehow generates wealth. I would argue, however, that for conservation’s sake we can hold some some apart from servitude.

“The question of whether conservative plants were distributed in similar ways historically or were more widespread is a topic of much debate in prairie conservation circles.” We (Europeans who basically stepped in it upon arriving on the scene) eliminated them by the plow and with our confined pasturage of livestock. It’s true that the extent of this is hard to fathom. But it’s really quite the opposite. This is a question I’ve only heard posed from people trying to justify grazing in the context of conservation as though painting over rust fixes things. The reliability of our ability to track “fragile” species down based on how far they are from the barn, what side of the fence cattle weren’t on, and other modes of separation from livestock and the plow makes no sense if these species were not once generally the typical ones. Their persistence at all, given their life histories, wouldn’t make sense otherwise.

“Two groups of Illinois entomologists have each developed their own index of prairie quality based on “conservative” insect species,” and “both of them have found that there is often little correlation between the number of conservative insect species and the number of conservative plant species in a prairie.” Why should there be? Anyone that dabbles in floristics knows that the pitfalls are misuse and misinterpretation are rampant. It’s the worst with richness and evenness. It’s still pretty bad with FQI. Mean coefficients of conservatism are better, and weighted coefficients perhaps better, but where prairie is degraded by a long history of mid-spring burning or broadleaf herbicide application and grasses with moderate coefficients are over-dominant, it can buffer against discernment of the real story (another chapter there). …but number of conservative species? Hmph. So let’s square the potential misinterpretation!

Prairie Ecologist writes at length about there still being a lot of Regal Fritillaries, Gorgone Checkerspots, and grassland birds on Kansas and Nebraska prairies as though that proves something. Regal fritillaries need their host violets. Their host violets avoid grazing by virtue of their low stature. Those violets remain on eastern prairies infested with “fragile” plants, and so do Regals in the rare cases that there is enough landscape. I sincerely doubt regals would fair any better on prairie fragments with “scrappy,” “hard-working” plants in Nebraska if 99.9% of the land was turned under by the plow, taken over by thicket, and developed. But the problem is that darn, regal-killing, “fragile” plant management! We don’t have big prairies, but the small ones we still have support rich, conservative flora…so at least we maintain the possibility of expanding those prairies in all their fragile richness from the species and genes that remain. How to do this is the frontier of ecological restoration in the Upper Midwest.

Maybe easy street is still having landscapes to work with, which are part of a prevailing agricultural economy rather than the opposite.

Prairie landscapes like this still support relatively high numbers of grassland birds, including greater prairie chickens, but that’s not because they are used for pasture, it’s because they are large, open landscapes.

Let’s pause for a moment to pose two questions.

1) Does one native species have more fundamental right to exist or importance than another? If so, where does the logic extend? Once you put a price on a species, wealth can always pay to remove it. This is true even when we put the value on something with no clear economic relevance. Ecosystem services are the biggest conservation own-goal of all time…in my opinion.

2) How many of the “fragile” species that are often abundant on less abused eastern prairies find their range edges eastern Nebraska and Kansas or farther east? The answer is many. Wood betony. Compass plant. Prairie dock. Leiberg’s panic grass. Senega snakeroot. Rattlesnake master. Prairie blazingstar. Prairie coreopsis. Sky blue aster. MANY more. …and many different, more western species come onto the scene. Historical importance of bison as consumers ramps up east to west. …so maybe it’s all a big misunderstanding?

A prairie ecologist said, “High quality prairies – using the botanists’ definition – tend to be small.” What?! Attribution please! Oh yeah, we’re under cover of thought experiment. I’ve never met someone that didn’t desperately want to buffer and expand a small, high quality prairie remnant by reconstructing prairie or at least promoting maintenance of grassland around it. We (and by we I mean botanists, ecologists, stewards) dream about big prairies! We look out over the corn and see a lost landscape! Exhibit A would be the Mounds View Grassland. Those darn Midwest-easterners are just full of surprises.

Talking about prairies full of “fragile” species, Prairie Ecologist says “it’s also clear that those prairies can’t be the sole focus of conservation if we’re going to preserve the entirety of prairie species diversity.” Well clearly, but are we preserving it by minimizing elements of prairie diversity with dire conservation needs, old growth grasslands that don’t recover from disturbance on human time-scales? We can’t preserve prairie species diversity without those small, remaining prairies, and what is the entirety of prairie diversity? Prairie chicken reintroductions? Wolves? Cougars? Repatriation of land to American Indian people? These things tend not enter discussions of working prairies, but ungulates sure do!

The crescendo, “If some of those prairies were managed for more heterogeneous vegetation structure they might become more valuable to many insect and wildlife species.” Is this just a case of all eastern tallgrass looking the same to someone coming from the western margin? Heterogeneity abounds. Wood betony creeps across the prairie like an amoeba, lowering the vegetation height. Gradients abound in soils and drainage with even subtle topographic undulations, but you can see them in the plants and their structure. And the prairies are calendar displays, different in every month, not just in bloom, but also form. Species relative abundances and flowering ebb and flow across years in response to fire and weather. The heterogeneity is there in space in time. It looks different. Maybe it’s just all the green out here. But Prairie Ecologist continues, “It seems to me that some of those larger prairies could accommodate some experimentation with summer fire, fire-driven grazing, and/or other less traditional management strategies by testing those strategies on a portion of each prairie.”  Why would we sacrifice something that is rare and just about as close to irreplaceable as you can get to manage for “scrappy” species in the name of heterogeneity? These are scrappy species. They are easy to establish. We could just put in prairie plantings to poke and prod at will. Why would we burn in summer or fence in large ungulates when those weren’t the driving factors behind the assembly of tallgrass prairies, and it’s not clear that anything is broken that needs fixing beyond our greed for exploiting land (other topics, but the most numerous large herbivore out this way historically was a familiar one, deer). Sometimes experimentation is held up as science, when it’s really implementation. And this is happening. Take the patch-burn graze debacle at Taberville Prairie in Missouri as an example. And it’s a threat, because having big ungulates on grass is truthy. People like it. Sounds right. Alan Savory gave a Ted Talk. Never mind it was a load of bull (not that we’re talking about that graft here). To many laypeople, it’s all the same. Calves romping in the grass in front of the sunset on humid summer evening? It’s happy nature. It’s a win-win as far as dinner is concerned. It sells. Green is green, so never mind that we’ve lost some grasses and wildflowers.

Prairie Ecologist rightly says, “Regardless of answers to the above questions, there is one thing I feel very strongly about:  Good prairie managers consider more than just their favorite plant species as they think about how to manage their prairies.” I have never met one whose goal is prairie conservation that doesn’t. This extends beyond plants though, and plenty of mediocre managers consider a lot. Good land management more than anything comes from listening to what the land has to say.

The post ends rather magnanimously. I’m used to people talking and writing this way, having grown up in Iowa. In saying things that might offend, here making a long list of assertions and painting with a broad brush, claiming it’s in good fun and appealing for open minds are tactics to disarm and deflect those that would disagree head on. This is innate rather than intentional. I’ll consciously end more abruptly. It’s not the botanists that threaten any of the prairies I know. That prize goes to neglect, and the silver goes to the bulldozer. Save Bell Bowl Prairie! Even if it’s small collection of fragile organisms.

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