Fringed Gentian: Genetics, Techniques, and Adventures

Could it be a formerly more widespread species of rich wet prairies and woodlands - that now survives mostly in specialized, alternate, or degraded habitats? 

This post explores how we at Somme have thought about a challenging, uncommon but not Endangered or Threatened species – fringed gentian (Gentianopsis crinita).

We spent hardly any time on it in the early decades of our work. We were somewhat prejudiced against it, as an “Oh My!” plant, too beautiful and unusual. We didn’t want to be distracted from, say, Leiberg’s panic grass, bastard toadflax, and hundreds of other species that seemed more central to our mission. Yes, we threw some gentian seeds around in 1979 and 1981. But subsequently, we focused our minds and resources on what we considered higher priorities: species on the Endangered lists and, our highest priority, figuring out what it takes to restore diverse ecosystem quality. (See Endnote 1.)

But fringed gentian turned out to be more interesting and, indeed, rarer than we thought. That’s especially so for black soil prairie and open woodland populations of the tallgrass region. (See Endnote 2.)

NatureServe map of fringed gentian populations is shown below:

The U.S. Dept. of Ag. maps occurrences of fringed gentian in the tallgrass region – by county:

Fringed gentian seems to survive in just one county each in Virginia and Georgia, two counties in North Carolina, but in ten to twenty counties per state in the tallgrass region. Yet this map may be misleading:

In 1994, Swink and Wilhelm's "Plants of the Chicago Region" showed similar counties but provided this comment on their “western sector” (the book's Wisconsin and Illinois counties): “The map suggests this plant is common in our western sector, but it is actually rare there.”  

Then in 2017, Wilhelm and Rericha's "Flora of the Chicago Region" lists Gentianopsis crinita for only five Illinois counties, pointing out that they could not confirm the earlier records for two counties. And black soil populations? So far as I could determine, the only black soil prairie or savanna in our region that retained fringed gentian was the one (not surprisingly) said to be the finest black soil prairie remaining in Illinois, forty magnificent acres on unincorporated land between Wheeling and Buffalo Grove. Sadly, tragically, immorally, this site, called the Chevy Chase Prairie after a nearby golf course, was intentionally bulldozed in 1977.

Destroyed, but there was a message: fringed gentian may have been a species of our tallgrass prairie. Finding no seed elsewhere, we of the North Branch got six pathetic seed capsules from the “only somewhat sandy” Gensburg-Markham prairie in 1979 (see http://vestalgrove.blogspot.com/2017/10/a-second-chance-for-fringed-gentian.html ). For years, all the genetic heritage surviving at Somme descended from those six capsules. Later we were excited to find that some Chevy Chase seed had been rescued from the bulldozers and a few plants bloomed in most years on protected land in nearby Long Grove. We got a little seed from there too – and broadcast it in the gentian habitat at Somme.

Still, the breadth of the gene pool represented by our plants seemed dismally narrow. As a rule, for most other species, we gathered seed in ways designed to maximize how much of the local gene pool would have the potential to contribute to the new populations. We did this by a) gathering seeds from as many as possible local sites (with similar soils), b) gathering seeds from those sites over multiple years, and c) gathering diverse components at those sites. For example, as much as we could, we sought to collect seed form the early-ripening plants, late-ripening plants, plants from drier and wetter areas, more-shady and less shady situations, etc. When we propagated seed in gardens, we sought to replace existing plants from time to time with plants from newly collected wild seed. We rejected seed from plants that "volunteered" in our production beds, as we were concerned that they could represent "cultivars" to some extent. Support for these approaches is suggested by later studies like that of Espeland et al. (2016) who wrote: 

Seed collection from wild populations is a first step in propagation of restoration materials (Basey, Fant & Kramer 2015). By taking a relatively small sample from a relatively large population, seed collection can cause genetic drift … Genetic drift can lead to an overall reduction in genetic variation and a greater risk of future inbreeding through mating between genetically similar individuals…

Genetic diversity (Ne) and phenotypic diversity have also been shown to confer stability at the ecosystem level... Key biotic and abiotic interactions that drive community structure and ecosystem patterns and processes are deeply affected by intraspecific genetic variation in foundation plant species. For example, the amount of genetic diversity within populations can influence competitive interactions between species and ultimately alter plant community composition … Genetic diversity can also drive community structure … and can sometimes be more important than interspecific diversity within the plant community.

Thus, for, say, compass plant, wild hyacinth, and dropseed grass, the Somme populations started with just a handful of original plants in a small area or two – but now represent gene pools from a dozen or more larger populations and a diversity of habitats at those sites. We wished that could be true for all species. If we tried harder, could we find more nearby gentian sources to draw on?

We had an additional concern when we began to restore savannas and woodlands. Like many older sources, in 1913 Britton and Brown characterized the habitat of fringed gentian as “moist woods and meadows.” Might “the gentians of the woods” represent other possibly vanished or vanishing genetic alleles?

As we started taking this species more seriously, we searched the scientific literature for clues but found relatively little help until the publication of a 193-page study in 1992 – a Ph.D. dissertation by Heather Jane Robertson. We learned a great deal from her impressive research along with her illustrations, below:

Robertson’s diagram above taught us how to recognize seedlings and first-year rosettes.

On the other hand, our overall conservation strategy was very different from the one suggested by Robertson. She treated this gentian as a single species conservation problem and therefore drew conclusions unlike ours. We were being coached to envision our species restored as part of complex and long-evolved natural communities, managed as much as possible by nature. (Even today, a lot of conservation takes that more limited, single species approach.)

Robertson may have been handicapped by working in a region where the surviving prairies and woodlands were much further degraded than even ours. She considered this gentian a species that “can only survive through a short part of a successional change from bare ground to forest.” She visited 26 populations – “almost all known sites in New York state.” Of those, only one seemed to be a surviving remnant of a natural grassland or woodland. All the others (except “landslips” were being managed by mowing or grazing or had been mined. (see Endnote 4). Thus, in her “SUMMARY OF CONSERVATION RECOMMENDATIONS,” she writes:

“Sites which are not kept open naturally, for example old fields or pastures (in contrast to landslips and other naturally open habitats), need continued, active, management to prevent encroachment by woody plants and development of a closed shrub and tree cover … Mowing or grazing vegetation to ensure that herbaceous plants predominate will allow G. crinita to survive.”

Robertson doubted the reports of fringed gentian growing in woodlands. As she put it:

“G. crinita requires unforested conditions. Plants were sometimes observed growing close to scrub edges or at the borders of open woodland that had few shrubs in the understory. If this is a general feature throughout G. crinita's range, it might explain the occasional published references to "thickets" and woods as habitats (e.g. Gleason 1952, Scoggan 1957). Alternatively there may be more shade-tolerant ecotypes in some localities.”

Or, as an additional alternative, perhaps there once were woodlands that had a great deal more sun than our “natural” woodlands do today – occurring as part of the fire-adapted landscape that included prairie, savanna, and open oak woodlands in all eastern states. As Robertson acknowledges:

“Fragments of prairie, or "oak openings," which now support G. crinita populations in Ohio (Easterley 1979) and western New York (my study) could have been significant for the survival of G. crinita in the forest period. Native Americans may have played a part in keeping such fragments open, for instance by burning them to encourage game (Seve ringhaus & Brown 1956).”

Still, when she gets to recommendations for conserving this species, she mentions mowing and grazing, but not fire.

At Somme, we have seen enormous fluctuations in gentian numbers from year to year. (See Figure 1.) Dr. Betz first described such fluctuations to us, in the more mature prairie at Markham. In one year, there’d be a big stand of gentians in a certain small area. Betz would check that area the following year and find none – but would find a big stand of them 100 yards away, in a place where he had found none the previous year. Perhaps, we thought, at Markham great numbers of seeds waited in the soil for many years, somehow deciding which year would be right to germinate at that spot (perhaps a north-facing slope, or south-facing, or with relatively more sandy soil, or silty, or with competition recently lessened by brush removal, or by the death of some short-lived plant). Later, the Robertson paper gave evidence suggesting no long-term gentian seed bank. Thus, another riddle.

Figure 1. 34 years of fringed gentian data at Somme Prairie Grove

Blow up this graph, and you can see that in some years there is actually a bit of red down low, showing that a few gentians bloomed. For example: in 2003, Somme had six blooming plants. In years that show nothing at all, perhaps there were none; perhaps there were some here and there, but we never found them tucked away in Somme’s 80+ acres; or perhaps we were just too busy to look.

If you’re interested in patterns and puzzles represented by the graph, you’ll find some of them discussed in this long paragraph. We got our six capsules of this biennial plant in 1979 and planted them in Miami Prairie. Two years later, we collected seed from the plants that bloomed there, and broadcast some of those seeds at Somme. So, the seven plants that bloomed in 1983 started the Somme population, which then had to wait another two years for 149 to bloom in 1985. Then comes another low year; a few plants emerged from 1983 seeds that perhaps had lain dormant for a year. The spectacular 900 plants counted in 1987 show an every-two-years exponential increase. But why were there so few between 1987 and 1996? Perhaps the ’85 and ’87 numbers had been flukes attributable to especially good gentian weather. Perhaps our average Somme conditions aren’t so good for this species? Or was it the deer? We do know from monitoring many other species that an over-population of white-tailed deer peaked in 1993. Those deer devastated many species that, like this gentian, were especially sought by the deer. Deer control programs by the Village and the Forest Preserve, beginning in 1994, could help explain the upswing that, on the gentian’s biennial schedule, resulted in the explosion in 1997. And the “Moratorium” on all management including fire for a few years subsequently (see http://woodsandprairie.blogspot.com/2016/05/after-miracle.html ) could help explain the drought for the next decade. A few years of stewardship by Lisa Culp Musgrave, specifically to help the gentians (see http://vestalgrove.blogspot.com/2017/10/a-second-chance-for-fringed-gentian.html ), may explain the surge and then drop from 2008 to 2012. The good numbers in 2017 rise may reflect the efforts of steward Eriko Kojima, who was an eager new seed-picker in fall 2015. She resumed gentian caging and seed collecting, and the increase in seed has allowed us to broadcast in many additional areas.

Perhaps, one of our experiments might be to stop assisting these gentians in some of the dozens of sub-populations in various parts of the site, to see how they’d do with no help.

Bi-modal Associations

One variable not illuminated by our counts of plants is the apparent bi-modal nature of this species habitat at Somme. We find it in two very different situations. It blooms in some of the highest quality areas – and some of the lowest. It’s not surprising that a biennial species might thrive in the low competition of areas newly freed from dense brush. Some of these “recent restoration” areas produce large numbers of plants for a few years and then dwindle to no plants, at least for decades. Perhaps "a seed bank will express itself" once a "healthy" conservative turf has established. Young restoration areas often pass from the “much bare ground” state through a “teenager” period where a few aggressive mid-conservative species demonstrate an “irrational exuberance” so ferocious that only the strongest survive. We do not find fringed gentian during this stage. But we do find it in later stages where conservative diversity has begun to restrain the mid-conservatives.

Since deer and voles wipe out some unprotected populations, we stewards collect seed from protected plants and distribute it where needed. We now skip the areas of aggressive mid-conservatives, as we’ve found it does not succeed there. But we broadcast seed in wet-mesic areas that seem to have available niches either because the more-restrained high conservatives are running the show or because brush or weeds have been controlled, and there’s plenty of bare ground. When we have collected and broadcast seed, we have mixed gentian seed from both habitats together. Perhaps we should encourage the development of populations adapted to the more sustainable high-quality areas by segregating the seed we gather in the high-quality areas and re-broadcasting that seed just in those areas. Or maybe our current seed mixing is the best way to give the Somme population(s) every opportunity to assemble the richest and best gene pool?

Lots of issues lurk in this photo, surrounding at least 60 blooms. 

On the left are the wide leaves of buckthorn, reminding us that without fire, this habitat would soon be gone. Most common other plants here are tall goldenrod and big-tooth sunflower – aggressive plants that can wipe out habitat for quality species. 

But also, down on the bottom left is cut-leaved water horehound. This species plus Dudley’s rush suggest that, despite the tall goldenrod, this area may be ripe for broadcasting conservatives including swamp betony, cowbane, winged loosestrife, and turtlehead. The "at least sixty" blooms suggest a plant that could produce 38,000 seeds, if the deer, voles, and insect larvae don’t eat them (see Endnote 8). Only one of those seeds has to triumph as another seed producing plant two years from now, for a stable population. But as we know, in many situations, none do succeed, and another population of this increasingly rare plant winks out for good. 

Finding More Diverse Seed

At first we feared that all natural, fire-dependent, black-soil tallgrass prairie and woodland populations of fringed gentian in our area (and all areas?) had been lost. So we started with the best we could get from “somewhat sandy” Markham Prairie. Later we were thrilled to get a few seeds from the very high quality, now-mostly-destroyed Chevy Chase Prairie (see http://vestalgrove.blogspot.com/2017/10/a-second-chance-for-fringed-gentian.html ).

But that’s a thin gene pool. Recently we’ve looked to expand it. It turns out that a lot of “beating the bushes” among conservationists turned up a few more survivors of original black soil prairie and woodland populations (See Endnotes 5 and 6). Thus, in fall 2017, we are able to expand the Somme gene pool with seed from three sites including likely black soil prairie, savanna, and woodland origins.

We’ve been recording associated species in our varied gentian populations. Will they provide clues over the years that will help with “conservation management” (or “sustainability building”)? And we are considering various experiments (see Endnote 7) and what monitoring would most effectively help us learn from them.

Another milestone: We broadcast seed in recovering wet open woodlands for the first time in fall 2015. Eriko Kojima reports fringed gentians there, in nearby Somme Woods, in summer 2017. One plant was in the sedgy apron of a woodland pond, two were in a sedgy meadow among the swamp white oaks, and “like five maybe” were in a drier restored savanna with bur and Hill’s oaks and an original population of the endangered dog violet (Viola conspersa) for that matter. The adventure continues.

Endnotes

Endnote 1. To give credit where credit is due, it was our great privilege as volunteers to be coached to experiment with an important, new, largely unexplored discipline which may well prove to have global importance – ecosystem restoration. In our early years, our principal supervisors, advisors, and mentors were the Forest Preserve District (FPD) staff (especially Chuck Westcott and Paul Strand), Professor Robert F. Betz (Northeastern Illinois University), and Ray Schulenberg (Morton Arboretum). Later, in response to our dedication and effectiveness, we were “adopted” by the Illinois Nature Preserves Commission (INPC) and The Nature Conservancy – and the breadth of our mentoring expanded to a great many universities and then-cutting-edge professionals in government and not-for-profit agencies. Still, we were the people working on these questions, day-to-day on the ground, as a volunteer community. We listened to advice, kept current on our authorizations from FPD staff, made our decisions, and did our work.

Initially, our vision and goals came mostly from Dr. Betz and George Fell (INPC). We wanted to rescue and restore what had been almost lost. But soon (thanks to the influence of younger conservationists) our fundamental goal became biodiversity conservation. We wanted to save natural communities with all their species and ecotypes – or alleles. Simply put, an allele is a variant of a gene. For example, as humans, we all have the same chromosomes, but one person’s chromosomes have the allele for, say, blue eyes while another has the allele for brown. In plants, varied alleles determine cold hardiness, drought response, disease resistance, defense against some insect or another, etc. An individual plant has only one or two variants of a given allele. In contrast, a population of that plant may have a great many variants.

As we worked, we had to translate the evolving scientific consensus into on-the-ground action. In the process, we became part of the development of new ways of thinking about the ecosystem. Yes, we were saving species, but we understood that the best and really only way to do so was as part of complex, long-evolved, and still-evolving natural communities, managed as much as possible by nature.

In our early days, “prairie restoration” seemed quite separate from “natural areas conservation.” But soon – because we were the only existing force that the INPC could enlist to manage many neglected preserves – we began to apply our invasives control and prescribed burning expertise to some of the most important ecosystem preserves in the Illinois (for example Shoe Factory Road Prairie, Nelson Lake Marsh, Thornton-Lansing Road Nature Preserve, Bluff Spring Fen and many others). As we did so, we naturally noticed that the little fragments of high quality were just pathetic scraps of survival surrounded by large “buffer” areas. It was obvious that the species of the “natural areas” would have much improved prospects if they could double or quadruple their population sizes by re-invading the invasive deserts that then surrounded them. Thus began our development of “First Aid” recovery techniques for natural areas, based on what we’d been learning on the more degraded “incipient prairies” along the North Branch. Our work on prairies soon expanded to savannas, woodlands, and wetlands as it became obvious that they too required restoration thinking and techniques.

Endnote 2. Not finding a conservative plant species in a prairie or woodland today may indicate little about whether that species was there before ecosystem degradation. Few black-soil sites today have prairie lilies, white-fringed orchids, or white prairie clover. Yet in the very finest such conservative species can be common.

The greater fringed gentian (Gentianopsis crinita or, in older books, Gentiana crinita) can be abundant today in sand the tallgrass region’s higher quality sand prairies and sand savannas. People report that the largest and highest quality black soil prairie in Illinois was rich with orchids and fringed gentians when it was destroyed in 1977. Even in sand areas, the fringed gentian is rare enough to rate monitoring by the Chicago Botanic Garden’s Plants of Concern program. But our rich soil prairie and woodland populations – if they once existed – are vanishingly rare today

A similar species, lesser fringed gentian (Gentianopsis procera or virgata) is more typical of pannes and fens.

Endnote 3.

This endnote starts with some genetics:

“Seed collection from wild populations is a first step in propagation of restoration materials (Basey, Fant & Kramer 2015). By taking a relatively small sample from a relatively large population, seed collection can cause genetic drift, that is, a change in the frequency of gene variants due to sampling, affecting population genetic and phenotypic variation and sometimes means. Genetic drift can lead to an overall reduction in genetic variation and a greater risk of future inbreeding through mating between genetically similar individuals.” 

(Espeland, Erin K. et al. 2016). 

A fundamental principle of biodiversity conservation is that we seek to save – not just all the species – but all the gene pool. If there once were fringed gentians in black soil prairie and associated woodlands, they likely had genetic differences from the sand populations. Sand prairies, fens, and other specialized habitats are precious and wonderful. But the rich soil prairies and woodlands were by far the largest (and thus most genetically developed?) ecosystems in the region. They’re now the most diminished. Fragmentation may be more problematic for them, compared to the sites and populations that were more fragmented on the natural landscape. Those genes may just want to flow and have fun.

Endnote 4.

Robertson writes about the single “prairie” habitat that she found in New York:

“Remnant prairie sites are also known as "oak openings" in New York State (Shanks 1966). The G. crinita locality was dominated by species typical of tall grass prairies of the mid - west (Shanks 1966), principally Sorghastrum nutans , Andropogon gerardii , and Schizachyrium scoparium . Other characteristic species included Asclepias tuberosa and Monarda fistulosa.”

Robertson found five gentian populations in “non-anthropogenic” habitats that Robertson called “landslips” which consisted of massive erosion areas on steep slopes:

“These were on unstable sloping ground, usually below earthy cliffs in glacial deposits, and were dissected with gullies. The sites had been colonized by the same species, both native and introduced, that were also present in most of the habitats resulting from human disturbance and management, i.e. the old fields and roadsides. For example Aster lateriflorus , Solidago canadensis , and Euthamia graminifolia were recorded at both kinds of site. Other less common species found on the landslips included Sheperdia canadensis and Lonicera dioica, and in wet areas Parnassia glauca and Equisetum variegatum.”

The International Union for the Conservation of Nature list the habitat for fringed gentian as “anthropogenic (man-made or disturbed habitats), meadows and fields (New England Wild Flower Society 2011-2015).”

Endnote 5.

Our original six capsules from Markham probably held about 300 seeds. We got fewer than that from the “black soil” Chevy Chase seeds. When we started thinking more seriously about Gentianopsis crinita, we were reminded of how thin the starting gene pool was. We reached out to people who might know of other populations.

Jim Steffen of the Chicago Botanic Garden alerted us to a small population near Lyons Woods – a black soil area that was originally mostly savanna and oak woodland. We learned that Lake County volunteer steward Joyce Proper in 1998 found some plants growing with other uncommon natives in an original savanna region south of Fox Lake near Grant High School (about 20 miles from Somme). She gathered seed of those gentians annually for six years and broadcast them in nine areas of a Lake County Forest Preserve where she is steward. It turns out that FP staff knew about that Lyons Woods population and authorized her to expand her gene pool with some of those seeds as well as others from a third nearby preserve with a more sandy soil. In 2017, Joyce sent us 2.5 tablespoons of the seed that resulted from those three populations.

Not surprisingly, most or all of the populations started from Chevy Chase seed invested in people’s backyard restorations are no more. But in trying to track them down, we discovered that Tom Vanderpoel of Citizens for Conservation secured seed from Chevy Chase, and healthy populations thrive in two of the CFC prairies. CFC generously donated about a tablespoon of CFC seed to Somme in 2017.

We also heard from Sarah Schultz, amanuensis for the veteran steward Barbara Turner, currently well into her eighties. Sarah wrote “Barbara and Timmie Clemetsen  ...  made several trips to the (Chevy Chase) prairie, only able to take as many plants as they could carry each time.  Parking was not close and Barbara remembers having to walk quite a distance, lugging bucketfuls of plants.  Bulldozers were ripping up the prairie as the ladies were rescuing plants.  More than once they were chased away by the police.  Timmie mentioned the property owner started to poison the plants to deter the rescuers.  They both said it was a stunningly beautiful prairie, such a shame that it was destroyed!”

Thus, thanks to Barbara Turner, Joyce Proper, and many others, the Somme populations of fringed gentian now include at least some of the gene pool that survived in black soil prairie and non-sandy oak (savanna or woodland) ecosystems. Thank you, all. We hope to retrieve more.

Endnote 6.

Part of our problem with the fringed gentian was that we were embarrassed by its history with us. It was a bit of a skeleton in our closet because it violated three of our principles: 1) it had come from far beyond our 15-mile seed source limit; 2) it came from somewhat sandy soil, and 3) it was illicit. When two new and important volunteers presented us with those original six seed capsules from a dedicated Illinois Nature Preserve, we did not (yet) have approval to gather them. That last sentence was an attempt at a polite way to say that they were kind of pilfered. It was our deeply held principle that we were to be ethical about all this. Personally, I was especially embarrassed that the seed came from the cherished remnant managed by our beloved mentor Professor Robert F. Betz. I was also torn about how to respond to the wonderful people who had gathered the seed, with best intentions. In the end, I called Dr. Betz and explained the situation. He was not happy. With heartfelt sincerity, I assured him that we wanted to recover from this and suggested that a) he approve it retroactively, b) that we spread the word that, as always, this seed was gathered with approval, and c) that we repay the seed to Markham (from our first harvest) with interest. He agreed, and we proceeded. On the other hand, we didn’t gather any more seed there so our gentians, for what they were worth, represented a very narrow gene pool.    

As for the problem of "beyond our 15-mile limit" - we later, as advised by our mentors, established exceptions to it. One such exception was for species that no longer survived within 15 miles - if they once were present within it. We'd seek seed in the closest places where they survived. The genes at Somme now represent three populations, one of which was originally within that 15 mile limit, and the other two were close. 

Endnote 7

Possible experiments: Really? Do we stewards have to do our own science?

Perhaps if I spent more time studying the scientific literature, I’d find scientific research results that would help me make on-the-ground decisions for ecosystem restoration and conservation. But I fear that time might not be well spent.

So – we sometimes ask: what experiments can we indeed do in a living ecosystem – that would help conservation? (And, for that matter, what might we do as “pure science” – because we just have a burning desire to know)

Below are six possible fringed gentian experiments. Most will take many years and will not likely ever be covered by a Ph.D. study or “official, funded science.” Do you, dear reader, have any recommendations? Thoughts?

1. Is it true that there’s no seed bank in nature? Leave some areas unseeded for many years, and see if gentians show up after long absence?

Challenges: This experiment may not be practical. It’s so easy to miss one or two plants in acres of dense vegetation. One plant with one flower can produce 600 seeds. An “explosion of plants where there had been none” could represent the progeny of such a single plant. Also gentian seeds can easily be spread when mud containing seeds congeals for a while on the feet of various birds and mammals.

Implication: If there’s no seed bank, then widely broadcast seed in prior habitat to help maintain a sufficiently large population to be viable. If there is none, refrain from seed broadcast to preserve whatever may be special about the genotype and seed bank of a given population.

2. What happens after the rise and fall of large populations of dodder (Cuscuta), dogwood (Cornus), sandbar willow (Salix), or the various diseases and other disturbances that have their impacts on high quality vegetation? Cycling among conservatives. Smooth white lettuce: similar questions. Are all conservatives long-lived, or are there some that cycle among each other (perhaps using up certain nutrients or attracting disease organisms when they’re too abundant). How might such changes impact the fringed gentian?

Implication: If a conservation site and population is too small to take advantage of such processes, knowledge of how they work could allow managers to move gentian seed to make up for the lack.

3. Fringed gentian currently grows at Somme in more than twenty widely scattered stations. Annually monitor each for gentian numbers and associated plant species. See if any group of species seems to correlate with increasing or decreasing numbers. 

Implications: Unclear, but useful hypotheses might emerge once we were to study the associates that emerged, and their order of appearance as populations rose or fell.

4. Are the genetics different for a gentian population assembled from many remnant populations compared to one un-ammended remnant population? If so, what do the differences mean? This would be a lot of work, but Nora Gavin-Smith is currently doing something like this with Somme and other sites’ populations of forked aster (Aster furcatus) Perhaps, all we need to do as stewards is to stick to our various and varied protocols and keep good records.

5. Might this species function at times as a monocarpic perennial?  Do lots of fringed gentians germinate every year – and then die back above ground when conditions aren’t right? We see a version of that with the short-lived prairie orchid (Platanthera leucophaea). It may emerge with a few leaves, or even flower buds, and then, if the weather is a bit too dry, wither above ground, sending resources back to its roots, and trying again the next year. (The orchid most often dies after first producing seed, but apparently some plants can produce seed for years – thus it’s not strictly monocarpic.) In the gentian’s case, the question is whether seedlings and roots might be able to survive for years, in nature? Thus, even without a long-term seed bank, the species might be able to wait for years for best conditions.

Note: Silvertown (1984) has argued (and to some extent demonstrated) that many monocarpic perennials have been misunderstood as biennials.

Challenges: Finding large numbers of first year seedlings and following them for years in the wild is indeed a challenge.

Implication: Similar to those in experiment 1.

6. Broadcast seed in high quality areas – using two approaches. For some areas, broadcast seed from where it’s easiest to get the most (large populations in degraded areas).  For other areas, broadcast the smaller amount of seed that can be “borrowed” or “pilfered” from the smaller populations in high quality areas.

Implication:  Managers could follow the approach that led to the best conservation result.

Overall Comment: These experiments may not be the highest priority for conservationists. But thinking them through a bit seemed at least a useful thought experiment. Perhaps it might be more important to do such experiments with Leiberg’s panic grass or bastard toadflax or other species which may be more important to the recovery of a sustainable (high quality) habitat for biodiversity conservation generally. Or maybe some people would be inspired to do this work on fringed gentian because it’s more fun and quicker. (Given that gentian is short lived, a ten-year gentian experiment might be equivalent to a hundred-year experiment on bastard toadflax.)

Endnote 8

It has long been known (e.g. Britton 1924) that scattering fringed gentian seeds in appropriate habitat will sometimes result, at least temporarily, in a new population. Unfortunately, we also hear that many of those populations die out over the decades. In our attempts to launch populations as self-sustainable as possible on the current landscape, such as it is, we found our standard ecosystem management (invasives control and prescribed fire) was not enough. We also needed to counter three types of animals. 

Careful monitoring revealed that deer sometimes eat every plant. For an annual or biennial with no long-term seed bank like fringed gentian, that is very dangerous. Our solution here was to protect a few plants in each population with wire fencing (see, for example, http://woodsandprairie.blogspot.com/2017/07/ted-talk-part-2-politics-and-science.html ). Since a single plant can produce tens of thousands of seeds (and perhaps receive pollen from all nearby plants?), we find that plant numbers often increase dramatically when some are protected from deer. (Citizens for Conservation has successfully sprayed vulnerable species with deer repellent.)

On the other hand, in some cases we found that many or all caged plants were eaten by meadow voles or white-footed mice. Voles (which can be reluctant to leave their grassy tunnels) are often deterred by ten-inch tubes of “hardware cloth” (see http://vestalgrove.blogspot.com/2012/12/wild-and-crazy-foxglove.html ). White-footed mice, which are great climbers, scramble over and through our cages, but tend to harvest much less than the voles, so, at least so far, we’ve just absorbed their impact.

On the other hand, insect larvae are even more insidious. In the case of Somme’s prairie gentians (Gentiana puberulenta), larvae sometimes seem to eat every seed before any substantial number ripen. (What kind of insect? In one case where we checked, the culprits were larval sawflies. Another attempt to identify the larvae in the seed capsules led us to the moth genus, Endothenia. The two types of larvae we find in the seed heads differ in one having a pointed head and the other rather a blunt head.) But with the fringed gentian, we find that if we harvest seed capsules as they ripen, we can pull them apart, find the nasty larvae, and remove them before major damage. 

Can any biologist can offer any info or guidance? 

We wonder if we could increase seed production by treating some of the seed heads with an insecticide at some point later than pollination time but before major damage has been done. So far, we haven't gotten any further with that than asking the question. We would hesitate to kill insects that were part of the natural ecosystem. On the other hand, increasing the currently pathetically small population of prairie gentians would much increase the populations of these malignant (?) or natural (?) insects. With increased populations, the gentians could likely cope on their own. 

References:

Basey, A.C., Fant, J.B. & Kramer, A.T. (2015) Producing native plant materials for restoration: 10 rules to collect and maintain genetic diversity. Native Plants Journal, 16, 37–53.

Britton, N.L. and Addison Brown, An Illustrated Flora of the United States etc., 1913

Britton, E. G. (1924). The fringed gentian - Gentiana crinita Froel. Torreya, 24, 102-103.

Espeland, Erin K., Nancy C. Emery, Kristin L. Mercer, Scott A. Woolbright, Karin M. Kettenring, Paul Gepts, and Julie R. Etterson. Evolution of plant materials for ecological restoration: insights from the applied and basic literature. Journal of Applied Ecology. 2016

 http://onlinelibrary.wiley.com/doi/10.1111/1365-2664.12739/full.

Robertson , Heather Jane. A LIFE HISTORY APPROACH TO THE STUDY OF PLANT SPECIES RARITY: Gentianopsis crinita IN NEW YORK STATE. Cornell University, 1992.

https://core.ac.uk/download/pdf/6103648.pdf

Silvertown, J. W. (1984). Death of the elusive biennial. Nature, 310, 271.

Swink, Floyd and Gerould Wilhelm, Plants of the Chicago Region, Morton Arboretum, 1994

Wilhelm, Gerould and Laura Rericha, Flora of the Chicago Region, Indiana Academy of Science, 2017

Acknowledgements

For help tracking down old publications, thanks to Gina Cordovi and Stacey Stoldt of the Lenhardt Library at the Chicago Botanic Garden.

For helpful editing and comments, thanks to Kathy Garness, Mark Kluge, and Eriko Kojima.