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Thursday, February 22, 2024

The "Wild and Crazy" Foxglove Returns

 


 

Too many so-called ecological studies are superficial to the point of uselessness because they focus on one to three species, for one to three years, on one to three acres. The ecosystem doesn’t work that way.

Stuart Pimm

 

We reported on the eared false foxglove in 2012 following a mere two decades of study. One hundred years ago, you had to “ride the crazy train” to find this easy-come/easy-go annual plant, as we then explained. Our study of how to facilitate this plant's recovery continues, and year by year we learn. 


Here's a key element of our thinking: we're not doing this one species at a time. We facilitate certain needy and possibly important species within the flow of life among Somme's nearly 500 plant species as the formerly lost but now recovering, black soil savanna ecosystem changes radically – on the road to recovery, we hope. 

 

In 2012 we had quoted the Center for Plant Conservation on the plant then called Tomanthera auriculata and now called Agalinis auriculata:

 

This species globally has “About 40-50 known occurrences, most with populations of only 25-250 individuals. The largest populations were found in Arkansas, Mississippi, and Missouri. Recently discovered in Kentucky. Presumed extirpated in Michigan, New Jersey and Texas.”

 

Today there are more populations known, in part because people plant this false foxglove in prairie restorations. Is this hemi-parasite sustainable in its restored and original populations for the long term? 

The eared false foxglove is now found in 17 states, although it is imperiled in 15 of those 

and gone entirely from 4 others. At best, it is considered merely "vulnerable" in 2 states 

and secure in none. Map by NatureServe. 

 

We first noticed plants at Somme in 1998 after broadcasting seeds from an original nearby population some years earlier. Then, we have no records, probably meaning we found none, until 2003 when 31 plants appeared near where we'd first found them. We caged some after we noticed deer eating them. Then we noticed that voles were sneaking inside the deer-exclusion cages and cutting down the foxgloves to get their seeds. In 2004, eighteen plants bloomed, but only one survived the deer and voles. 


Dense areas of tall goldenrod and saw-tooth sunflower grew nearby. As we'd found these species sometimes inhibited more conservative vegetation, we began cutting them in hopes of expanding habitat for the foxglove, which seemed to work. We began a program of facilitating grown of the foxglove population by caging, scything, seed harvest, and seed broadcast to see if we could give this new species a better chance of finding niches at Somme.  


Our early monitoring is summarized in the graph below, showing modest numbers during this species’ 16-year long, iffy incubation period in the prairies and savannas of Somme Prairie Grove. Would it survive here? And then in 2011 – apparent success – at least for the short term:

 

Indeed, for three years after that report, numbers remained high. We stopped giving this species “intensive care” and didn't monitor it at all in 2016 and 2017. But when we counted in 2018, we found 54 plants. In 2019 we counted only 20.

 

Perhaps we should have felt fine about those low numbers, as they were in the range of what the Centers for Plant Conservation cited for the size of most populations. But as an “introduced” or “restored” population, it deserved a more skeptical look – especially for this kind of plant. As an annual, this false foxglove has to start over from seed every year, while growing in an ecosystem of highly-competitive perennials, densely packed. 

 

Another troubling sign – we noticed that most of the Somme plants predominantly grew in immature, temporary habitats – the very opposite of what we are working towards at Somme. Yes, perhaps this wild and crazy species has always depended on “disturbances” – but to survive here it would need to find niches in the kinds of disturbances that occur within relatively stable communities. Given where we had been finding most foxgloves, our big numbers did not indicate that it had found those niches yet.

 

Here four foxglove plants grow among slender mountain mint, sweet black-eyed Susan, slender gerardia, gray dogwood, foxglove beardtongue, saw-tooth sunflower, yellow wood sorrel, a few thin whisps of an oval sedge (perhaps Carex tenera), willow herb, Kentucky bluegrass, and a deer-eaten cream gentian. These low- and mid-conservative species comprise an attractive proto-savanna assemblage, but not a long-term stable community. With additional fire, time, and seeding it could develop into a quality prairie or savanna herb community. 

 

Here, five foxglove plants are growing with spotted Joe Pye weed, saw-tooth sunflower, sneezeweed, grass-leaved goldenrod, and narrow-leaved mountain mint. This is an even poorer-quality restoration at this point. No grasses or sedges. Few shorter-statured plants. No conservatives. Far from relatively stable. Our experience has been that such areas increase in quality over time, with regular burning and seed broadcast. If that happens here, will the resulting habitat continue to work for the eared false foxglove? 

Natural communities have evolved over millions of years to be “relatively stable.” They are characterized by highly-competitive, diverse, conservative plant species. They are now rare in the tallgrass region (and most of the temperate world). When, for biodiversity conservation, a formerly extirpated species is restored to a site, there’s a good chance that it could fail because of missing symbiotic pollinators, fungi, bacteria, and other associates. 


Somme Prairie Grove has the potential advantage that it’s partially original savanna and prairie remnants. Some crucial invertebrates, fungi, and other species may be surviving in small numbers. We found that when we broadcast seeds of the federal Endangered prairie white-fringed orchid, the fungus that it totally depends on was still here. A study by U.S. Fish & Wildlife found that very fungus in the restored plants' roots at Somme. Similarly, when we started restoring structure and quality to savanna with fire, thinning, and seeding, entomologist Ron Panzer found the formerly undetectable Edwards Hairstreak butterfly – a savanna specialist – to become the commonest hairstreak on the site. According to Dr. Panzer, it had likely been surviving here in small numbers and responded to restored habitat. 

 

Panzer’s research also found that larger, merely good-quality areas retained populations of remnant-dependent insects that no longer survived in some smaller sites that had been judged to be high-quality on the basis of conservative plants. Are the false foxgloves and other restored species here reestablishing relations with needed fungi or bacteria? We’d like to know.

 

Two periods of intensive care have both worked well for this species at Somme – but principally on the largely bare ground of young plantings. We broadcast vastly more seed in 2022 and 2023 than ever before – mostly in fair to good recovering communities. Thus, we expect to learn a lot more in 2024. 

 

The restoration of the Somme Prairie Grove black-soil savannas is testing a hypothesis. The number of plant species is up from about 250 when we started to about 500 now. How many of those species are here for the long term? Will these methods restore a substantial, high-quality, diverse, conservative community that has otherwise been lost? And might various now-rare species turn out to play a substantial roles? Or not? 

 

In areas with hundreds of big plants, cages somewhat protected some, but hundreds of other uncaged plants fared just fine last year. 


Some might argue that the eared false foxglove doesn’t even belong in the Somme savannas. Many modern sources refer to it as a prairie species. But one possible reason for that is that there’s so little savanna left to study. The standard old floras – Fernald (1950) and Gleason (1952) – both list its habitats as prairies and open woods. Like savannas, open woodlands aren’t what they used to be, but if a species lived in both prairies and woods, it seems likely that it inhabited the savannas too. Wilhelm and Rericha (2017) give today’s habitat only as prairie, but the prairie associates listed include slender gerardia, Canada rye, tall coreopsis, and cream gentian – species that may be less characteristic of prairie than of savanna. 

 

Ecologist Ken Klick with the Lake County Forest Preserves prepared a list of species that “may become extinct within Lake County Forest Preserves within the next decade.” The list included glade mallow (Napea dioica), bearded wheat grass (Elymus trachycaulus), Seneca snakeroot (Polygala senega), and awnless graceful sedge (Carex formosa) – all species that have dramatically increased in Somme’s savanna areas. Because of the way patches of shade and sun vary dynamically in savanna – as trees grow, blow down, burn, and die – it could be that savannas offer special advantages as annual species look for niches where they fit.  

 

Klick expressed concern that some of these species may depend on the restoration of natural conditions that are not today part of most natural areas management regimes. We hope that our “savanna restoration” experiments at Somme might help answer the questions Klick raised and inform biodiversity conservation efforts generally. 

 

As Reed Noss wrote in 1996, “If you think protecting species is hard, just wait until we try to protect whole ecosystems.” Many such efforts are now under way. Some fail. Some seem to be heading towards successes. We can learn from both.

 

References

 

Carter, Dan. Good discussions about similar issues in Wisconsin can be found at: https://prairiebotanist.com/ 

 

Fernald, M. L. Gray’s Manual of Botany. 1950

 

Gleason, H. A. The New Britton and Brown Illustrated Flora 1952 

 

NatureServe info is at: https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.148670/Agalinis_auriculata


Noss, Reed, Ecosystems as conservation targets. 1996. Trends in Ecology & Evolution 11(8):351

 

Ron Panzer, personal communication, 1992

 

Stuart Pimm, personal communication, 1995


Our previous report on this species at Somme can be found here


A good overall conservation summary for this false foxglove can be found at: https://www.dnr.state.mn.us/rsg/profile.html?action=elementDetail&selectedElement=PDSCR01130

 

 

ENDNOTES

 

Endnote 1.

 

What have we learned so far about the eared false foxglove?

 

Although this species often does well where brush was cut, in most such places it goes away after a couple of years and doesn’t come back. Bare ground where brush was cut is not a long-term habitat here. We will not for much longer be cutting dense brush at Somme Prairie Grove. It’s almost gone. 

 

If we give this false foxglove “intensive care” (caging, seed harvest, and seed broadcast), it can increase exponentially. We try not to rely too much on our limited expertise on this plant. While we broadcast some of the seed we harvest in new areas that look similar to where the foxglove has prospered, we also add some of the seed to our wet-mesic prairie and savanna seed mixes, so that it ends up in more "random" places. Often it emerges where we've planted the seed mixes in areas that "didn't look right" for this plant ... and fails to emerge in the areas that seemed "just right." 

 

Little tubular vole exclusion cages can help. Taller ones (10” to 12") work better than shorter ones (6”), but do not work all the time. Indeed, the voles sometimes climb over the top, then down to the bottom, then section stems, gradually pulling seed heads down. (Tying the seeds to the tops of cages prevents the voles from pulling them down.)

 

If we just wait for the seeds to spread, mostly they don’t spread very far.

 

We haven’t yet found this species doing well in any of the higher-quality associations at Somme. But then again, it’s a wet-mesic species, and we have very little wet-mesic high quality so far. (Recovery seems faster in our mesic and drier communities, perhaps because these burn more frequently under today's conditions.) Our goal is to establish high-quality prairie, savanna, and woodland throughout the site, as much as possible. 

 

This false foxglove does well at the edges of saw-tooth sunflower patches – not in the centers of them.

 

Two species of parasitic morning glory called dodder (Cuscuta grovonii and glomerata) seem to help the hemi-parasitic false foxglove. Dodder is a valuable "regulator species" that can dramatically set back over-dense patches of saw-tooth sunflower, slender mountain mint, and others. Where dodder thinned out such species, it seemed to leave intermixed plants of the foxglove mostly alone. 

 

A highly-respected botanical research institution, at our request, recommended scientific experiments to help us better understand our eared false foxgloves. The recommended protocols included carefully counting numbers of seeds and placing them in a wide variety of plots and transects in spots carefully chosen to represent a variety of factors. All seeds were placed in areas of relatively stable vegetation, sometimes near existing false foxglove patches in similar vegetation, but not within them. It was a lot of work, compared to what we usually do. The educational result was that not a single false foxglove emerged from any of the seeds planted for these experiments. We learned that you can’t just pick small areas for it and seed there. It could be that this species, in areas of competition, requires special conditions that we don’t recognize. Thus, we seem to find it succeeding among competitive vegetation only here and there, and only when we broadcast seed to the wind over wide areas.  

 

Endnote 2

 

What do we want to learn?

 

Does the fact that the voles seem to eat all plants of this species in many places reflect a) some artifact of the modern world, b) this species lack of adaptation to this site, or most parts of this site c) the fact that we broadcast its seeds in the wrong places?  Perhaps this foxglove doesn’t normally survive to produce seed in thriving grassland but instead in thin areas where brush recently burned back or bison trampled a lot. Such areas represent both less competition from other plants and less cover for voles.) 

 

Voles tend to get it just as the seeds start to set. Are there approaches to spraying stinky vole repellent that would work better than caging? The repellent does seem to work. Would it also repel pollinators if we spray it too early? 

 

Might this species do better in some other specialized niche – that we’re not recognizing and where we are thus not broadcasting seed?

 

Will it in time adjust and show up sporadically (perhaps in places where brush has burned back or where dodder, fungus or some other stress has reduced competing vegetation)? 

 

Does it not belong here, in the relatively stable communities we are striving to restore? Will it fade out and be gone from Somme without a lot of "horticultural" work, that would violate our current long-term goals here?  

 

Are there better approaches through which we could continue to pamper it for a while and at the same time do a better job in facilitating better adaptation to existing or emerging niches? It’s a globally rare savanna plant that could be another Somme Prairie Grove success story. Or failure story? 

 

Acknowledgements


Thanks to Christos Economou and Eriko Kojima for many helpful edits. 


Graphs by Linda Masters


Most "intensive care" work on the eared false foxglove in recent years has been done by Eriko Kojima and Sai Ramakrishna. 

 

Prescribed burns and overall supervision credit goes to the Cook County Forest Preserves staff including burn manager Steven Ochab and ecologist Anna Braum. . 

Friday, February 2, 2024

Rare Grass vs the Leave-It-Alone Hypothesis

It was growing in the wrong county and the wrong habitat, at least according to the current books.

But tell that to the grass!

And rare? It's certainly rare in the region and habitat where we found it. Wilhelm and Rericha (2017) show it absent from Cook County and all counties north and west. They do show it in all counties to the south and east of Cook - but growing on sand. At Somme Woods, it suddenly turned up under interesting circumstances in rich woodland.

The name of the plant is deer-tongue grass (Panicum or Dichanthelium clandestinum). Wilhelm and Rericha give its habitats as sandy "wet to dry habitats, often in thickets." Their associated species lists cover just two sandy habitats "wet-mesic to mesic woodlands in the dunes region" and "dry-mesic to dry sand prairies."

Unusual for a grass, this species has wide horizontal leaves. Unlike the similar wide-leaved panic grass, the leaf-sheaths of deer-tongue grass are furry, 

The experts are usually right, but not always. And conditions have changed. Older books often have very different reports on where species were found back then. For example, H.S. Pepoon's Flora of the Chicago Region (1927) reported that deer-tongue grass in "woods north and west" (of Chicago) - like where Somme Woods is. He characterized this species as "frequent." 

Many plant species that were once more widespread survive today in some of their former habitats but not in others. One striking example of that emerged from a kind-of-bold experiment by steward Barbara Turner. Her woodland had long been in Turner's family, and she continued to manage it when it was dedicated as Reed-Turner Woodland Nature Preserve in 1980. Until that time no Nature Preserve woodland had ever been recognized as needing fire. Barbara, a careful observer and former student of May Theilgaard Watts, was concerned that some of the rare species (including pale vetchling, on the Illinois Endangered list) seemed to have faded out nearly everywhere. Advisors recommended a burn and, indeed, she received the first ever permit to burn a Nature Preserve woods. That burn had dramatically positive results, but no pale vetchlings emerged. For many species, when they're gone, they're gone.

Barbara's lawn and house were adjacent to the preserve. One day she said, "We call it a lawn. But it's just more woods that happens to have been mowed occasionally. What if we stop mowing?" Indeed, as she stopped mowing and started burning, up popped the pale vetchling as well as another plant, then unknown in Lake County, violet bush clover. (We later found that clover growing nearby with rich savanna associates along the edge of a railroad right-of-way.) These species had survived in the area where mowing kept it sunny - but not the shade of the brush that had build up in the "preserve." Shade kills. And there's little "seed bank" from most species in woodlands. 

Back to deer-tongue grass - at Somme Woods there was a "picnic grove" that had been mowed since the Forest Preserves purchased this land in the 1930s. The mowed area had widely spaced old white and bur oaks, like the adjoining preserve. About two decades ago, steward Linda Masters suggested a switch from mowing that area to restoration and burning. When the mowing stopped, the North Branch woodland seed mix was broadcast there.  

But we didn't then just leave it be. We occasionally selectively scythed tall goldenrod from the area, as that seems sometimes to facilitate the establishment of a desirable conservative turf. And additionally, a couple of years ago we noticed that, from the adjacent never-mowed edge, woodland sunflower seemed to be invading and shading out the otherwise increasingly rich, restored vegetation. So, as we sometimes do, to see if it would help, we started selectively scything that dense sunflower too. Happily, when we did it, we noticed what seemed like a familiar quality plant we hadn't seen here before, wide-leaved panic grass, reaching unusually high toward the sun, in the shade of the woodland sunflower.   

But one day as we passed by in 2023, it just looked seriously wrong. We studied it. It was deer-tongue grass, a species none of us had ever seen. When we looked more carefully, we found another plant of that same species, about 20 feet away, also on the scythed edge between the mowed lawn and the "preserved" woods. We wonder if we would ever have seen it if we hadn't scythed but "just left the place alone." 

But now the question became: how could these plants have gotten there? Was this an example of the Barbara Turner experience, where a species had survived where occasional mowing kept aggressive competitors at bay? Perhaps its partly-mowed stems survived in the brighter sunlight, but the species was lost from the community where the un-mowed woods had grown increasingly dense? Or had it arrived on someone's shoe, or the wheels of a mower, years ago? For a variety of reasons, all three seemed unlikely. But there it was. 

So the questions became: what to think about it, and what to do about it? Should this species just be left alone because we are unsure what to do? Should it be pulled out as a possible invader? Should deer-tongue grass seed be harvested and spread, because that added diversity would restore integrity and benefit the woodland ecosystem restoration? Is this a recovered, nearly lost species here? Or is it somehow spreading north because of global warming? And if seeds of this species go into the Somme seed mixes, should it then be another species shared among all the North Branch Restoration Project seed mixes? 

The Somme Woods work was conceived by its original Forest Preserve staff and volunteers as what has seemed to many to be a noble experiment. The goal here has been much like the Somme Prairie Grove experiment, that is, restore all species that would likely have been there, and let them work it out, after a period of providing biodiversity with various kinds of help for at least the short term. Does deer-tongue grass fit into that vision? For now, we're just watching it to see how it behaves. 

But how should we think about a plant like this? 

Endnotes

Here, the deer-tongue grass in the foreground is joined by diverse other species including three in flower:  nodding wild onion (pinkish white), elm-leaved goldenrod (yellow), and woodland Joe Pye weed (pale purple).  

The upper part of this photo gives a better sense of how dense the now-scythed vegetation had been becoming. The somewhat aggressive species include tall goldenrod, woodland sunflower, woodland Joe Pye weed, and tall coreopsis. 

Deer-tongue panic grass is on the left. Wide-leaved panic grass is on the right.
Notice that the sheathes (that cover the stems beneath the leaves) are furry in deer-tongue and smooth in wide-leaved. These grasses are shown here side by side for comparison, but typically, with us, the deer-tongue is taller and more erect, and wide-leaved is more spreading. 

A person could argue that deer-tongue grass shouldn't get special care because, at C = 4, it is less conservative than many of the species increasing here, including wide-leaved panic grass at C = 8. Someone else might argue that diversity is key, including the full range of species of the natural ecosystem from C = 0 to C = 10.  

Acknowledgements

Thanks for comments and suggestions to Becky Collings, Christos Economou, and Eriko Kojima.

Friday, January 26, 2024

Destructive Herbicide in the Ecosystem

Course Correction: From being “Invasives Killers” to “Biodiversity Conservationists”

 

Wake-up Call

Most of what we conservation land managers do works well and is profoundly important. But we also have to look at the parts that need fixing. Conservation land management can be wasteful, destructive, and incompetent. 

 

Both staff and volunteers want our work to be successful. On paper, it looks good for hard-working professionals to secure grant funds, have contractors work on X number of acres, and put that in a report, as if that's a sufficient measurable accomplishment. But such measures – of dollars spent, acres covered, and percent successful invasives control – leave out what’s most important. How much did the long-term integrity or health of the ecosystem improve, or deteriorate?

 

Most of us want to be positive as much as possible – especially when the challenges are so great and the resources so small. But that’s also why it’s important not to waste. The five stories below are true and more common that we wish. We need to think about how to do better. Sites aren’t identified, mostly so the facts can be presented forthrightly, without antagonizing the good people in charge, who are doing their best in most cases.

 

This post is not an “anti herbicide” protest. Wise use of herbicide in biodiversity conservation is utterly essential. Above, buckthorn, which has been re-sprouting here after every fire for decades, has been sprayed efficiently in fall, after most other species have gone dormant. The herbicide, recognized by blue dye, is clearly also damaging some desirable species. There’s often no practical way to avoid some losses. But the adjacent species will quickly fill in where the buckthorn died. It would be possible here to avoid killing any other plant, and some perfectionists feel great angst over this kind of thing. But if we followed their advice, we’d use up too much time, and a great deal of other dearly-needed work would not get done.   

 

Five Examples of Dismal Failure

 

1. Complete death of very high-quality prairie

 

A Grade A (very-high quality) mesic black-soil prairie was deteriorating from brush, mostly gray dogwood. Diverse prairie survived under the dogwood, but diminishingly. Professionals (from a contractor with a rep for taking extra care) painted the stems with the herbicide Garlon in winter. The whole prairie died in the areas where they worked. Next summer the ground was bare, except for small re-sprouts of the dogwood, which had the most vigorous root system. Despite covering a small part of the prairie, the death of a substantial patch of Grade A was a profound tragedy. 


This heartbreak baffled many experts, who evaluated after the fact. Many people assured us that they had done “this kind of thing” without the negative impact. But was it really the same? How carefully had they studied the prairie vegetation before and after? How similar was the weather? How similar were the volumes of herbicide applied? We wish we knew. Many of us are doing more experiments to learn what we can. Fortunately, in a way, few people need to worry about impacts on Grade A prairie, because there’s so little of it. Unfortunately, saving Grade A areas is a highest priority. Do we have insufficient knowledge to do it right? 


Dense stems had been cut and painted in a different, poorer quality area nearby. In that area too, the prairie died, as shown below. 

On the upper left, the dogwood was not cut or herbicided. 

On the lower right it was. But the remnant prairie died. 

For more detail on this incident, click here


2. High-Quality Woodland Loses Diversity from repeated Reed-Canary Mistakes

 

A rich woodland had patches of invasive reed-canary grass here and there. Contractors seem to have recognized the quality of the intermixed herb vegetation and carefully sprayed only that invasive grass. Instead of a grass-specific herbicide, they used Round-up, an herbicide that kills most plants. While they eliminated the reed-canary in the centers of the patches, they failed to spray the reed canary at the perimeter of the patches, which was hidden beneath the quality vegetation. Perhaps they were unable to see it underneath the good plants, as they worked quickly to spray the many patches in the contract area. But the result was that the dead zones where the Round-up had killed the remnant vegetation grew larger and larger over the years. 


A better approach is to carefully and assertively spray the reed canary at the leading edge of the infestation, even at the cost of collateral damage, in order to eliminate the patch once and for all. The staff people in charge said they hadn’t had enough time for more detailed monitoring. It was as bad a loss as if those areas had been plowed … or had a Burger King built on them. We have to do better. 

 

3. Foliar Spray in Good Quality Woodland Kills All – Even the Old Oaks

 

Here’s another case when the supervisors were stumped. How could this happen? 

 

In an oak woods of hundreds of acres, the volunteer stewards made slow progress on invasive brush. Contractors were hired to help out and demonstrate effectiveness on two acres. They cut adult buckthorns and sprayed the dense seedlings. On paper, for the short term, the results looked excellent. Dense patches of seedling and sapling buckthorns were entirely dead. You could walk around the distinct edge of the two sprayed acres and see a sharp line between where buckthorn in the treatment area was brown and dead – and the adjacent area was green with young buckthorn. But by the end of the summer, all the trees had died too. Some were old bur and white oaks, many feet in circumference. 

 

I asked questions about it but didn’t want to push too hard, so as to maintain a good relationship with the owning agency. Staff explained, “Perhaps they put a brush pile in the wrong area.” Clearly they hadn’t looked carefully – or even paid much attention to what happened.

 

A year later, I asked the contractor if they ever figured out what the problem had been. The fellow was surprised by the question. Staff had never asked them about it, and the contractor hadn’t been back to check. He claimed not to know what herbicide his company had used. People clearly hoped the problem would just go away. (See Endnotes 1 and 2 for some expert opinion on what had happened).  

 

At that point, I wondered if I’d made a mistake by not saying more at the time. I’d worried about provoking a backlash that might have had negative impacts on that agency’s overall program. But we need to understand this stuff. And by “we” – I mean to include volunteer stewards and advocates, who can be more willing to say that ‘the Emperor has no clothes’ when needed. Especially at this stage of knowledge, just leaving the evaluations to  overworked staff is not good enough. 

 

4. White-fringed Orchid vs. Canada Thistle

 

The Federal-endangered prairie white-fringed orchid (Platanthera leucophaea) can grow in very high-quality grasslands and sometimes in degraded ones – but very few of them grow anywhere. Last year’s census by the U.S. Fish & Wildlife Service found only 223 plants. It’s a truly rare species.

 

One degraded prairie had scores to hundreds of them blooming every year. Then, saw-tooth sunflower over-ran parts of the orchid’s habitat and mostly eliminated it. We scythed the sunflower for a few years – hoping that this treatment would help quality vegetation recover. Gradually, the orchids returned in good numbers, and other quality vegetation like smooth phlox and yellow stargrass increased. Another problem – the invasive alien, Canada thistle, was a minor presence. A contractor working in a nearby area sprayed it, despite being  asked not to do. Thinking that they knew better, they sprayed it, rather aggressively, with Round-up. The recovering prairie was badly set back. Many aggressive species began shading out the more conservative ones. In recent years, other aggressive species dominated, and few orchids bloomed there.  

 

5. Mighty Mowers followed by Massive Broadcast Spray

There are ferocious machines that can mow mature buckthorn and other brush and turn it into inches-deep “slash.” Top-killed brush resprouts the following spring, and broadcast spraying can control it. This approach can be very helpful for restoring large areas under some conditions.


Dense buckthorn can be controlled by mighty machines followed by heavy herbiciding (as shown above) or by “basal-barking” (as in Dismal Failure example 1.) 

 

What happens in oak woodlands that retained areas of remnant biota? We’ve seen this treatment wipe it out, including endangered species, and very probably much of the symbiotic soil biota as well. 

 

Perhaps a standard practice in such areas should be to set aside some of the best remnant patches for more discriminating approaches. Then the biota of these areas could spread through the rest of the woodland over time. 

 

Comparing Two Approaches 

 

Consider crown vetch, an invasive that can wipe out large areas of good prairie or savanna:

 

Approach 1. We know sites where people have been spraying “the same” crown vetch for decades. It just doesn’t go away. They complain loudly and cynically, but it’s their own fault. 

 

Their strategy? They go after the worst areas first, where they can kill the most with the least effort. Their work becomes endless whack-a-mole.

 

Approach 2. We know sites where crown vetch control was successful. That is, it’s now gone. What was the difference? 

 

The successful folks start with the smaller patches in the highest quality areas and eliminate them. They GPS or mark them on the ground and return every summer for a few years to give the final spritzing to any re-sprouts or seedlings. They search diligently around the former patch edges, as that’s where the vetch will most likely be holding on. In higher-quality areas they use one of the newer herbicides that are somewhat selective about which types of plants they control. Bit by bit, as time and resources permit, they go after the bigger patches in the poorer quality areas until those too are gone. 

 

Who’s In Charge Here?

 

All the concerns implied above are potential problems whether staff, volunteers, or contractors are doing the work. When, instead of a contractor, a staff person does the work, the person who evaluates results is typically that staff person. Given levels of resources, perhaps there’s no alternative. Most academic research doesn’t help with these questions. We need more practical, applied, insightful research by people who understand this field. 

 

At some sites, expert volunteers do the most sensitive and demanding work – often taking more delicate care than it would be possible to pay contractors to do, given current budgets. Some volunteer stewards take time to study the results of extra-detailed care and write up results. At some sites staff do excellent studies and learn from each other. Perhaps there should be some sort of clearinghouse where we all could record what we’ve learned, especially as it concerns the varied approaches that work best according to different soils, ecosystem qualities, weather conditions, etc.? And some knowledgeable editor could make the info easily accessible to practical on-the-ground folks.  

 

There are also broader problems that need discussion, study, and more-detailed best management practices. Remnants and all higher-quality areas need different practices and types of oversight than badly degraded sites. Perhaps a new profession is needed, sort of a “general practice doctor” for the ecosystem, who can recognize needs and recommend expert practitioners. That person wouldn’t mostly do the work but instead would evaluate, prescribe, review, and revise. People with such expertise would likely come from the ranks of on-the-ground restoration practitioners with extensive experience.    


Is killing invasives our goal? Or restoring integrity and health to the ecosystem? Herbicides are needed. But herbicide treatments may solve one problem while ultimately not helping, or even making things worse. Restoration requires a wise overall plan with appropriate sequencing. The work then needs close oversight by someone who has a good working knowledge of the site’s ecology and the long-range impact of possible treatments.

There are too few people capable of providing expert supervision and review. We’re not learning as fast as we could. Contractors (some dedicated and competent, some not) are often hired on the basis of the lowest bid, and no one has time to carefully evaluate the results. Or someone checks only whether target plants died – with little attention to negative impacts. The highest concern in remnants should be for the remnant species.

 

Endnotes

 

Endnote 1. Imazapyr

Dan Carter wrote: Do you know what herbicide they used? This is a common error made with an herbicide called Imazapyr. Milwaukee County Parks staff killed a bunch of trees at Wehr Nature Center by spraying lesser celandine with it. 

 

Endnote 2. What happened to those old oaks?

Another peer reviewer wrote: Since the buckthorn seedlings were densely packed, the same thing may have happened as with the dogwood clones above: too much highly concentrated herbicide migrating in soil directly or with the help of underground fungus, killing oaks by the root.  Herbicide labels have a “maximum use rate” given in amount of herbicide product applied per acre per year.  That is not the same as the maximum rate to control a given weed, which is stated elsewhere in the label.  Max use rates may be related to such failures as this one.  Or did root grafting occur between oaks & buckthorn?  As Dan Carter has said, the decision to use basal bark or foliar when desirable vegetation is present above or below ground is rarely a good idea.  Basal bark may work in such situations with a meticulous applicator & flawless technique, but such people are so rare it doesn’t warrant recommending that practice in general.

 

Acknowledgements

Thanks for helpful suggestions from Dan Carter, Christos Economou, Eriko Kojima, and two anonymous reviewers. This post also benefitted from written exchanges among Don Osmond, Dennis Nyberg, Dan Carter, and others as found here and here:



 



Friday, January 19, 2024

What is a Grade A woodland?

Ignorance kills. New priorities needed. A new tool shows promise.

 

Rare species are important. Rare ecosystems are immeasurably more important. But they’re often ignored (and therefore lost) because conservationists have not yet developed sufficiently practical and effective tools needed to save them. 

 

Perhaps the first point to make in this post is that there seem top be no Grade A woodlands left. All are degraded. Some may be able to recover high quality with good stewardship.


Serious biodiversity conservation began when we first understood that the last high-quality prairies were vanishing. (How important to an ecosystem is "high quality" - and how is it defined? See Endnote 1.) Savanna conservation emerged later, out of what we were learning from the prairies. 

 

Still, nobody much noticed the oak woods. Common? Boring? Obviously ‘disturbed’ (at a time when ‘disturbed’ meant ‘degraded’). To some, the woods seemed to be benefitting from 'natural succession’ – which was seen as a ‘good’ or ‘beneficial’ process, leading inexorably to something better (beech-maple forest). Those people were wrong. The deep-shade-tolerant flora of the maple forest do not return because they'd not been there. The result of increasing shade is not the rich flora and fauna of a forest; the result is degraded woodland, low diversity, and ecological ill health.  


Higher quality woodlands have been losing their species at the rate of 2 or 3% per year. At least, that’s what was happening to the few sites that have been carefully monitored. A few percent may not at first seem like much, but those losses continued to add up. In the 1980s, some of us advocated that oak woodlands, long protected from the ‘destructive’ impacts of fire, actually needed to burn. With trials and careful monitoring, in time a consensus emerged that fire had positive impacts and more and more woodlands gradually benefitted, somewhat. Yet few or no “very high quality” oak woods were being found and celebrated, and the gradual species losses even in Nature Preserves mostly continued. 


A degraded woodland under restoration. Some would say that no truly Grade A oak woodlands survive in the tallgrass region. For photos of one of the best, see here

As for this post, all the photos come from an attempt to restore quality to Vestal Grove. In the photo above, the herb flora is rich and compact but still has a long way to go in comparison with a top quality remnant. The very old trees are bur oaks showing spreading limbs – or the 'amputee stumps' of such limbs. The 'middle age' trees are mostly red oaks and hickories without lower limbs. As trees continue to be thinned and overall light is increased, perhaps we'll see more bur oak reproduction with persistent spreading "woodland grown" limbs on their lower or mid-height trunks. 


One trillium blooms with wood betony, golden Alexanders, and rue anemone. Other species visible include cut-leaved toothwort and starry campion. The tree trunk belongs to one of the many shagbark hickories. It shows fire damage at the bottom. Many woodlands today have excess numbers of red oaks and hickories, as those species reproduce more readily in fire-starved habitats.  


In 2016, a “wake-up call” made a big impact and indeed led to the “new tool” featured in this post. Dan Carter was part of a crew that evaluated an obscure site for a boat launch. Were there “environmental impacts” that needed to be avoided or mitigated? The Wisconsin Department of Natural Resources (DNR) was proposing an improved road, parking spots, handicapped access, and other facilities at Army Lake.

 

The road was to reach the water through an oak woodland which turned out to be “jaw-droppingly intact” – indeed, apparently the highest-quality remnant in southeastern Wisconsin and perhaps in the whole state. (There’s apparently nothing of comparably high quality in northern Illinois.) As requested, that survey team (employed by the Southeastern Wisconsin Regional Planning Commission) checked and found one Endangered species, forked aster (Eurybia furcata) and some wetlands. The write-up called for avoiding or mitigating any loss of those plants and or wetlands. (Why were those two categories thought to be deserving of special care? See Endnote 2.) 

 

The survey team's report identified Army Lake's rare woodland as the site’s most important feature. 

The other concerns paled in comparison with the importance of the remnant oak ecosystem. The Nature Conservancy's ranking shows high-quality oak woodland as “G-1” – globally endangered. (How is quality determined? See Endnote 3.) 


Sadly, the ecosystem didn’t seem to count. The one Endangered plant species and the peripheral wetlands both were recognized as meriting care. But no protocol then existed to authoritatively identify the incomparably more important woodland community as a priority. It didn't fit into any official category of concern. 

 

As it stood then, Army Lake Woods included ¾ acres of very high quality, ½ acre of good quality (very restorable) and in between about ¼ acre of badly disturbed land (ultimately restorable and therefore potentially invaluable to the long term sustainability of such a gem). Thus, we had here a prospective restored globally-endangered woodland of 1.5 acres. But it was not to be. 

 

Official channels function in mysterious ways. Sometimes they succeed in their intended goals. In this case, they did not. Some of the old oaks were cut, and about ¼ acre of the very high-quality natural area was bulldozed. It was a painful loss to Carter. This defeat established a clarity in the minds of Carter and others. The system wasn’t working. 


An important principle is: Never waste a major loss. Transform failure into a ‘teachable moment’ and inspiration for needed change. Carter reported on the disaster and, at their invitation, teamed up with Wisconsin DNR conservation biologists Amy Staffen and Matt Zine (along with Wisconsin Nature Conservancy regional land steward Brian Miner and others) to create the new official and authoritative “Monitoring Protocol for Assessing Baseline Condition and Restoration Progress in Oak Woodland.” See Endnote 4.

 

This inventory and monitoring tool could have a long-term impact. Wisconsin and Illinois (among leading states in natural areas conservation) have been weak in evaluating woodland sites (See Endnote 3.) If this tool is a step in the right direction, it will be for two principal reasons. It could help us recognize what remnants most merit conservation. And it could help us determine whether sites under management are stable, improving, or declining. 


Currently, such evaluations are made for most preserves on the basis of one person’s judgment. Often the judge is the person responsible for management, and of course it can be challenging to declare your professional efforts a failure, even if the reason is lack of resources. Also, the one-person’s-judgment process has no transparency. Government doesn’t work well in areas that no one reviews. Funding for conservation comes only with public backing. Volunteer citizen scientists, advocates, and stewards can be crucial ... if they’re empowered … and if they empower themselves.  

 

Biodiversity conservation is popular in the abstract, but it needs more public understanding and support. One way to get that is through more transparency and public participation. The new tool does not deliver automatic protection for sites like Army Lake, but it can aid our evaluations of high-quality and restorable oak woodlands, an important next step. 


Endnotes

 

Endnote 1. How important is "high quality" and how is it defined?


The future of life on Earth depends on its ecosystems. As we (to some extent necessarily) manipulate and simplify, we may one day desperately need the planet's once most common and now rare species. Certainly, we need their rare genes for agriculture, medicine, and industry, but we also may need some to restore an out-of-balance planet that has begun staggering toward poisonous rain, loss of oxygen, or insanely high temperatures. Ecosystems maintain balance, powered by the sun.  


Natural areas conservation was inspired in part by Grade A prairies. They are so rich. The INAI showed that only 1/100th of 1% of the original prairie survived as high quality. We cannot perceive all the components that constitute ecosystem quality or integrity or health. They certainly include all the interdependent plants, animals, fungi, bacteria, soils and all manner of soil biota. 

 

In the past, conservationists slowly began to realize that ecosystems lose biodiversity in response to over-grazing, plowing, draining, the elimination of predators, and other changes that helped us for some purposes. Aldo Leopold, while employed by the U.S. government to eliminate the threat of wolves, learned that "the mountain fears its deer." As Leopold succeeded and the deer massively increased, many plant and other animal species dropped out. No one at that time checked on how the fungi and bacteria were doing.    

 

Indeed, our overall understanding of the ecosystem is still primitive. But those gorgeous, intact, rich prairies made some people think, and act. A Grade A prairie typically has 20 or more plant species per ¼ square meter - and most of those plants are rare conservatives. A typical degraded prairie may average five common species per ¼ square meter. Conservative plant diversity is believed to be a good indicator of ecosystem health. The hope is that, if a remnant is big enough to sustain them, the other biota will be there too. 


What does "Grade A" mean? The definition changes. The Illinois Natural Areas Inventory defined: 


"Grade A - Very High Quality" as "Relatively stable or undisturbed" and 

"Grade B - High Quality" as "Late successional or lightly disturbed" 


with the more detailed explanations including language like Grade A: "does not show the effects of disturbance by humans" and Grade B: "not disturbed so heavily that the original structure and composition was destroyed." 


But in recent decades it's become increasingly clear how profoundly Native American humans - through fires, hunting, etc. - influenced the "original" nature that Europe-derived science studied. How far back should we consider that "origin" to go. For most of the richest tallgrass area, the ecosystems began to assemble only 12,000 or so years ago when the most recent glacier retreated. But, bless them, scientists have also demonstrated that many of the species and relationships go back hundreds of thousands to millions of years. They can move and re-assemble over time if given the chance. 


So how should "high quality" now be defined? Perhaps the definition could now be: 


A high quality remnant ecosystem is one that has most of its biota surviving in the structure and richness that assembled over thousands of years. 


Perhaps no rich Grade A savannas or woodlands survive. Very few come even close to the plant diversity of the best prairies, but some of the best do. Perhaps high-quality woodlands can be restored from the healthiest remnants?


(Note on soils: The INAI community classification separated areas by soil type. Sand prairies, savannas, and forests are considered separately from those on good soil, which have sometimes been referred to as "black soil savannas" or "rich-soil savannas." But the INAI just called those "savannas." Thus you have to read carefully to determine whether Illinois' savanna remnant heritage amounted to 11.2 acres (INAI Technical Report numbers for dry-mesic and mesic savanna in Table 6) or 1,300 acres (Technical Report's introduction). The difference reflected the much greater survival of sand savannas, as sand areas have not been as intensively used for agriculture and are less vulnerable to many invasive species. The potential for confusion on woodlands is even greater, as the 1978 Inventory did not distinguish between forests and woodlands. For some details of the 2011 revision of the Inventory, see here.)   

 

 


Endnote 2 Who started this?


Much conservation as we now understand it goes back to Silent Spring by Rachel Carson in 1962. Summarizing its impact, historian Jill Lepore credits Silent Spring with launching “environmentalism” as a global force and in the U.S. provoking the efforts that resulted in Clean Air Act (1963), the Wilderness Act (1964), the National Environmental Policy Act (1969), the Environmental Protection Agency (1970), the Clean Water and the Endangered Species Acts (both in 1972). Thus there is now widespread recognition of the importance of  wetlands and endangered species.      

 

Rachel Carson and Jill Lepore “have a way with words.” They’re both worth studying for that reason alone. Lepore praised Silent Spring by saying that, in the history of the planet, books with that much global impact could be counted on the fingers of one hand. Actually, the way Lepore put it reflected Carson’s many previous books, all of which reflected her love of the ocean, its tide pools, and biota. Thus, Lepore actually wrote: “The number of books that have done as much good in the world can be counted on the arms of a starfish.” (from “The Deadline” by Jill Lepore, 2023.)


Endnote 3. How do we Evaluate and Monitor ecosystems?

 

It’s relatively easy to measure Endangered Species numbers and the boundaries of wetlands. But for high quality ecosystems? Some details can be measured. But the vast universe of species and the interrelationships that make up ecosystems are for the foreseeable future beyond our grasp. So we need indicators.

 

Up until now, most people, if they measure or evaluate natural communities at all, use one of two methods: the Natural Areas Inventory method or various Floristic QuaIity methods. Both have advantages and disadvantages. 

 

The Inventory approach was developed in Illinois through the work of John (Jack) White and others in the 1970s (see Endnote 5). Their judgements were based on "lack of disturbance" and richness of conservative species. The resulting Illinois Natural Areas Inventory taught us how to recognize ecosystem remnants and where they were, leading to the acquisition of most of the best ones.  

 

This approach did great on prairies but found little in the way of black-soil savannas. Curtis in 1959 in Wisconsin (under the name Oak Openings) had found savanna to be the most common ecosystem type in the southwestern half of his state. Oak openings were found to have covered an astounding 5.5M acres,  with forests at 3.8M acres, and prairies at 1.5M acres. (These figures for “approximate original area” lump mesic and dry-mesic for forests and prairies, as Curtis lumped mesic and dry-mesic for savannas on rich soil as “oak openings.”) Savannas had been major habitats in Illinois as well, but remnants had been degrading even more quickly than prairies. Indeed, none were surviving with conservative diversity equivalent with what the best prairies exhibited. Had they once had it? As we learned, we began “saving” and “restoring” savanna as best we could. When developing global priorities in the 1980s, The Nature Conservancy gave savannas the highest priority, G1, Globally Endangered.

 

Neither Curtis nor the Inventory recognized mesic oak woodland as a community separate from mesic maple forest. They seem to have been blinded by “succession” theory. Oak woodlands weren’t seen as hallowed eternal nature; they were considered a temporary state, recovering from disturbance, on the way to maple forest. 

 

Yet as biodiversity conservation was studied, we began to recognize that the species of oak woodland were being lost. Species don't evolve over night. Woodlands (like savannas) are ancient communities that depend for their integrity on regular ‘disturbance’ by fire. Some of this history is discussed in Endnote 3. 

 

The Illinois Natural Areas Inventory focused too much on lack of disturbance and, for long term use, depended too much on judgment. Different “experts” had different judgments. Once the highly-trained original team had gone on to other jobs, their work was difficult to replicate.


The Wisconsin approach suffered from their system's Curtis-based approach, which did not recognize the significance of mesic woodlands.  The Coarse-level Monitoring Protocol (2023) presented (and linked to) in Endnote 4 is a new approach that could help conservation practice catch up with the evolving science, in the context of  a less-individual-judgment-based system. 

 

The Floristic Quality approach was developed by Gerould Wilhelm in 1977 for a study of the vegetation of Kane County, Illinois. It became highly influential when it was expanded to cover parts of four states in Plants of the Chicago Region (1994). It had the advantage that all competent experts would arrive at the same results. It had the disadvantage that experts did argue about what those results meant. Summaries of this method and references are here, here, here, and here


Wood betony grows in both woodlands and prairies. In the prairie it tends to be yellow. In woodlands, limited experience suggests that it's often reddish. Millions of years of co-evolution with hummingbirds have resulted in some species evolving red flowers. (For more on that, see here.) Much less-obvious genetic richness may be hemorrhaging from oak woodlands as animal, plant, fungal, bacterial, and other species drop out. Small sites of high quality have better potential for sustainability if nearby land can be restored to sufficient quality to support those species that need it.


Endnote 4. The new protocol.

The new woodland protocol will be posted in the Wisconsin DNR website. It's currently posted in full hereFor comparison with an officially posted protocol for savanna, look here. For a criticism of this sort of approach, see Endnote 6. 

For some excerpts of the new woodland protocol, see below:



Endnote 5

Perhaps we would take our leadership responsibilities and opportunities more seriously if we were to reflect on how greatly our region contributed to the origination of "ecosystem conservation" and "natural areas" stewardship. Henry Chandler Cowles (U. of Chicago) launched ecosystem study in the early 1900s. His student May Theilgaard Watts (Morton Arboretum etc.) wrote the books that raised constituency for it from 1957 to 1975. John C. Curtis (U. of Wisconsin) in 1959 scientifically defined the region's ecosystem types. John (Jack) White (Univ. of Illinois etc.) supervised the Earth's first Natural Areas Inventory in the 1970s. For more see Some History of Biodiversity Conservation.

Endnote 6.

One "peer reviewer" of the draft of this post wrote:

I have to be honest, I don’t really like these checklist scoring sheet type approaches. The scoring calculation seems just as arbitrary and any other approach, and they try and force things into categories too much. 


I understand their appeal (as you’ve outlined), but they aren’t my cup of tea because I have seen so many bad ones that are limited in their utility and are untested and uncalibrated with actual data. They often work in the limited context from which they were created, but when you take them to another site, they don’t apply as well. They are often created, and barely get used, ending up in the dust bins of history.  


But Floristic Quality as an approach remains widely used and increasingly so --- in large part because it is so simple and easy to use. But, it too is not well calibrated with actual data.  And its limitations and strengths aren’t well flushed out.


A few more photos and comments are below: 


The rather dense grass in the top half of this photo is awned wood grass (Brachyelytrum sp.). Perhaps it's so dense that the Coarse Metric would give this area a lower rating. Then again, this grass is not even on the Metric's list of woodland species. Is it naturally more characteristic of maple forest?  The same questions could be asked about large-flowered trillium, big leaf aster, and some of the other species mentioned here. No one really knows the appropriate status of most species in the tallgrass region's oak woodlands. The Metric is based on field knowledge and judgment. It and other methods should improve as we continue to learn more from remnant and restored areas. 


Above, the densest species is big-leaf aster (in bloom). This area in recent years had been increasingly rank with woodland sunflower and dewberry - "Native Indicators of Degradation in Oak Woodland" according to the new Wisconsin protocol. Scything them led to increases in more conservative flora including big-leaf aster (in bloom), zigzag goldenrod, awned wood grass and many others. Will such "facilitated diversity recovery" in time be adequate to control the sunflowers, briars, and other "thugs"? Work and time will tell. It is truly so very much fun to learn how to be good stewards of biodiversity. 


At Somme we have evaluated restoration results using both judgment and FQI. We have experienced such FQI positives as increasing site FQI and mean C, transect FQI and mean C, and average quadrat FQI and mean C. All those measures have consistently improved. Yet we’re far from confident that all proceeds well. Part of the “improvement” may be that woodland sunflower (C = 5) is massively replacing tall goldenrod (C=1). In the early stages, no problem. But over time, there are some indications that this sunflower will shade out (or allopathically reduce or eliminate) many species that had seemed secure. Our four-decades-long experiment definitely seems still in an early stage. 


John Taft pointed out (personal communication) that our species per quadrat and FQI numbers were still rather low compared to a site in southern Illinois that he had been sampling. But that site was substantially drier, more intact, and on much poorer soils, so it was not altogether comparable.


In restoration, different species respond differently to different approaches. Rue anemone (in bloom above) did not establish from our seeding. It was restored only through transplants from quality areas being bulldozed for housing developments. Individual transplants sat there, not reproducing, for decades - but now bloom in some areas by the hundreds. Most species came well from broadcast seed, but some, like big leaf aster, had minor success until more quality developed. Now it thrives in many areas after decades of existence as tiny, scattered leaves here and there. 

Some parts of Vestal Grove have developed a rich spring flora. Prominent above are wild leek, bellwort, and trillium. Will they be reduced as summer-blooming species increase? If so, people may miss the massed flowers of spring flora here. (Notice that there are few spring flora species on the Wisconsin list of woodland indicator species.) But there'll be plenty of rich spring flora elsewhere, for example under maple. 


We considered this area well on the way until, influenced by the new protocol, we noticed that the only trees in this area were hickories, red oaks, and hop hornbeams. A fine woodland may have such areas and such species. But good management should result in bur oaks reproducing here. This recovering ecosystem will probably see its original oaks reproducing and coming to dominate, soon, or decades from now. Our goals are very long term


Acknowledgements 

 

Thanks for helpful comments and edits from Greg Spyreas, Dan Carter, Matt Evans, Fran Harty, Rebeccah Hartz, and Eriko Kojima.