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Saturday, August 29, 2015

Does "Fire Pink" Make Much of a Difference?

Is it practical? … or is it even a good idea at all? … to restore an uncooperative plant to Somme?

We had tried in various ways with fire pink (Silene virginica) from time to time since the 1980s. But how much time was it worth? We had hundreds of species to deal with. Indeed, at this point Somme Prairie Grove has more than 480 native plant species (about twice the number that survived on this mostly beat-up site when we started). We concentrated our restoration efforts on the species where we got the best return for x amount of input. (Okay, we also put extra effort into endangered species or those, like bur oak and hazel, which had some obviously critical role to play.)

So, ho hum. Fire pink is pretty. But we didn’t see it as having any crucial importance. Also working against this species, seed was hard to find – and then it led to little success from the few seeds we did get. Occasionally we did notice a plant popping up here or there from the few seeds we did broadcast, but the species didn’t seem to “take.” Other species exploded from a good deal less work – including many rare and conservative ones[1].

(That number at the end of the last paragraph indicates an “end note.”)

Then unexpectedly in 2015, despite years of failure, fire pink (Silene virginica) began to demand another look. One new advocate turned out to be the ruby-throated hummingbird. Some rare species of butterflies, mushrooms, snakes, and birds were returning to Somme as the restoration proceeded. One of these in recent years was the hummingbird (a regular migrant, but rare as a breeding bird here). A tiny predator of small insects and valuable pollinator of certain flowers, it seemed to deserve help.
Beginning in 2014, male and female humming birds were seen at Somme all summer long, performing their
spectacular mating flights, and most likely nesting. In this photo the young male is nectaring on cardinal flower.
But hummingbirds search in vain during late spring for co-adapted red flowers. Where’s the fire pink?!
Because insects generally don’t perceive the color red, hummingbirds are the principal pollinators of red flowers. Those flowers and this bird are adapted to each other. Our ecosystems don’t have many red flowers, but where hummingbirds live there is a progression of red species that bloom in turn throughout the growing season. The list for us includes scarlet painted cup, columbine, fire pink, Michigan lily, figwort, and cardinal flower. Perhaps it would strengthen the resilience and sustainability of Somme’s oak ecosystem if the hummingbird/red-flower component were to be completed such that these “cogs and wheels”[2] were restored to functionality.

Three fire pinks do live in a little “nursery strip” alongside the garage at Linda’s and my house in a subdivision on the edge of the preserve. This nursery is unlike the seed-production gardens for Somme restoration that sprawl over much of our yard, where all the rare plants fight it out and compete more or less as in nature.

In contrast, the nursery strip is for species (many of them characteristic of very high quality ecosystems) that just don’t compete in our yard. For these pampered few, like two-flowered Cynthia and rue anemone, we very carefully weed out most other plants. The strip is a refuge for the temporarily[3] needy. A plant or two of fire pink has bloomed in that strip most years, alongside maybe a couple of juveniles, but we hadn’t given them as much help as they would have needed to graduate from “surviving” to become “thriving seed producers.”

Partly we hadn’t paid attention because they produced little seed, and what they did produce mostly just fell on the ground. It’s hard to harvest. Fire pink seed doesn’t turn brown to tell you when it’s ready. Ripe seed also doesn’t stay long on the plant. The green seed capsule just turns down and drops seeds on the ground clunk.

But this year, they’d increased to three blooming plants, and we said, “Okay, finally, let’s try harder.” That meant we had to spend a few minutes every day kneeling in front of fire pinks, carefully searching for capsules that were starting to droop. Those quiet zen moments led to our next surprise. Repeatedly, as we “prayed” before these plants, we’d hear a “whirr.” Then, turning slowly to that side, we’d come nose to bill with a hummingbird giving a look that seemed to say:

Isolated "nursery garden" for a few "special care" species.

“What are you doing in front of my flowers!? These are on my route, and I’m making my rounds. Get out of the way!”

If the hummer goes to such trouble to get these plants pollinated, how can we not help it and move this species up the priority list? Of course, that flip and frivolous question begs a more serious one: what is our purpose restoring all these species to Somme?

The answer below is not meant to dismiss the value of other types of restorations. The people who make restoration decisions have many legitimate goals. They may include: Pollution control. Endangered species recovery. General recreation. Better hunting and fishing. Shoreline protection. Biodiversity conservation. Aesthetics. Historical re-creation. Education.

Most of those do not much apply to Somme. To review our goals, we need to go back to decisions made in the 1970s and 80s when this long-term experiment began. The decision-making team was headed by Forest Preserve District officials (especially Superintendent of Conservation Roland Eisenbeis, Chief Landscape Architect Richard Buck, and Crabtree Nature Center Director Charles Westcott). They decided basic principles and relied for many details on advice from the best experts they could find, especially Prof. Robert F. Betz of Northeastern Illinois University as well as the staff of the Illinois Nature Preserves Commission. The decision-making also included the people who were to implement the plan; it was a good process. Thus the team included local staff people and the volunteers of the North Branch Restoration Project. The volunteers may have been fun-loving, but they were also serious, intelligent, curious, receptive people who put great dedication and creativity into finding ways to implement the Forest Preserves mission[4]. They were so generously ambitious in part because they were respected and empowered by the staff. It was a good relationship.
Fire pink seeds and the green capsules they fall from. The stewards at Somme choose seed to gather and sow
according to plans and goals carefully chosen by Forest Preserve staff and collaborators.

One phenomenon that Dr. Betz and many others had noticed is that when you find a very high quality site and give it a few controlled burns, the diversity is astounding. Researchers said, again and again, “I wouldn’t have expected all those species to pop up;” yet there they were. Very “high quality” sites are so rich because they had been “evolving their diversity” over thousands of years and during that time species had found niches where we wouldn’t have expected them. After a few burns, nearly every prairie species would show up on a fine 100-acre site; nearly every woodland species would show up on a fine 100-acre woods (at least all those adapted to the site’s wetness and soil types, and usually quite a few more).

In the case of high quality remnants, the “prescription” was to burn, control invasives, and otherwise leave them alone. For most of the largely degraded North Branch sites, the prescription that seemed to have the best chance to restore full natural diversity was to put back all the species that were likely to have been there, and then let them fight it out. But there was a complicating factor. Many rare species that thrive in the complex diversity of a healthy ecosystem would, it turned out, not compete well or even survive among the rank, aggressive species of a young restoration. They could be restored later. We’ve watched for decades as areas being restored gradually became more and more able to support the highest quality plants. 

If we had perfect knowledge and unlimited resources, it might have been a good idea to wait years or decades before broadcasting the seeds of some of the most rare plants. But it was impossible to predict which would survive where. And we had a deadline. The sites where we were finding and
In the darkening understory of unburned oak woods, thousands of rare plant populations
were being lost forever, along with any locally-adapted genetics.
gathering the seeds were rapidly being lost. Most seed sources would not be around ten or twenty years hence. That was sometimes because prairies and woods were being bulldozed for “progress.”  But it was also because some of seed-source plants lived in “preserves” that were not yet being cared for. Their “most conservative” species were often the first to die out as the degradation set in. Our challenge, at that time, was to conserve what we could. We had to find seeds from vanishing populations, choose recipient sites, and develop successful techniques – while we had the opportunity. Otherwise whatever was unique to those vanishing gene pools would be lost forever.

Fire pink is conservative. In conservation, “conservative” is a term for species that are rarely found outside a high quality natural ecosystem. Dr. Betz made one of the first lists of such species, for prairies. Later Gerould Wilhelm also ranked the wetland and woodland flora according to its conservativeness (Swink and Wilhelm 1979). Similar rankings have subsequently been made for states and regions across the continent. A fundamental goal of biodiversity conservation, gradually becoming understood, is to restore and maintain sufficient ecosystem quality that conservative plants and animals can survive. Wilhelm gives fire pink the highest rank – a ten. A perfect ten.

The Other Spring Flora

Most Illinois forests have lost most of their species in the last 200 years[5]. A few woodlands are prized for their spring wildflower displays. Those in the know often talk about “spring ephemerals.” These are the species that deal with excess shade by emerging in early spring and closing up shop when the leaves come on the trees. They finish their entire growing season in a month or two (in many cases going dormant for the rest of the year even before spring itself is half over).

But there’s another component of spring flora – at least as important and wonderful, but little considered. That’s the spring flora that is not ephemeral. Some spring-blooming species go on to function as a part of the ecosystem all growing season long. Rich associations of these species survive in but few places. Fire pink is one of these. Among many others are grove sandwort, woodland phlox, hepatica, robin plantain, bellwort, two-flowered Cynthia, and woodland blue-eyed grass. This kind of spring flora, the kind that requires ample light all summer, has an even more difficult challenge than the “ephemerals.” They, along with the flora that blooms in summer and fall, are largely gone from most woods. Shade kills.
Conservative plants do well together. Here early meadow rue, hepatica, wild geranium and Penn sedge make a turf. We wondered, would fire pink do better planted here than it did on bare ground in typical woodland restoration? 

When we studied the sites where fire pink was surviving, we noticed it had some great company. A plant’s “associates” are important. Very high quality (very healthy) natural woods, prairies, and wetlands have a look that surprises most people. These truly natural ecosystems often look “civilized,” restrained, neat – the opposite of “rank.” Many of the plants are short. Sunlight gets all the way down to the “understory” species. Fire pink lives among such companions. It pals around with conservatives. Associated species listed by Swink include rue anemone, woodland fescue, wild licorice, shining bedstraw, hepatica, wide-leaved panic grass, woodland phlox, Jacob’s ladder, and bloodroot[6]. A place where masses of these grow together is a special place. Very few if any “restored” preserves have reached such a state. Many experts think they never will. Others believe that figuring out how to maintain or bring back that level of quality and health is one of our top forest conservation challenges. If we don’t, many plant and animal species will likely die out or never return to most sites.   

In summary, at least new three ways of looking at fire pink convinced us that they needed more special care:
1.     They support the ruby-throated hummingbird (and associated species).
2.     They help fill out the “non-ephemeral spring flora” niche.
3.     They interact with other rare species to consolidate a conservative turf.

So here’s what we did

We originally found fire pink at two places within our 25-mile limit for local woodland seed. The first was Deer Grove (twelve miles) and the second was Reed-Turner Woodland (ten miles). As approved by the owners, we tried to collect seed. It wasn’t easy[7].

On a very few occasions we found a very few seeds. Following our usual practice for hard decisions, we’d split the little haul in two, throw half the seeds into a seemingly receptive part of the Somme ecosystem, and plant the other half in propagation gardens. I remember the little garden I maintained in back of my apartment building near Ashland and Irving Park in Chicago. I also “remember” that I forgot about putting pink seeds there. Then one year I noticed a few little plants in that garden that I didn’t recognize. The plants were “rosettes,” circles of prostrate leaves, lying low, building up energy in their roots, to make more of themselves later. I remember wondering what species those little newcomers might be. Having invested many kinds of rare seed in that garden, I suspected that whatever they were, they were likely special. I kept my eye on them. Finally one year they put up flower stalks, and one day out popped the dazzling red of fire pink. Rejoice.     

I got few seeds from those beauties though. First the seed would be unripe, and then they’d be gone. When my building went condo, we brought the plants to our new house by the forest preserve. (Linda often tells people that I planted the plants before I unpacked any belongings. Well, of course I did.) It was here that we learned the need to prospect for ripe seed capsules so carefully that we’d hear the whirr of hummingbirds while harvesting.



The photo shows how many seeds we got in 2015, our first substantial harvest. This little saucer-full might not look like much to you; it looked fabulous to us. Shouldn’t we have gotten better at this faster? Yes. But we had other stuff to do. How many seeds did we get in 2015? It would be fun to know. (If anyone takes the pains to count them in the photo, put a comment on this post.) Perhaps 1,000?

Now for the first time we have to take seriously the next question, where should these precious embryos go? Tossing them out at random would a waste at this point. We’d done that in the past to the few seeds we got, with little success [8].

Perhaps we were sowing in the wrong places. Perhaps the mistake had been to invest seeds in new restorations. Much of our annual wild harvest gets planted in recent brush-cut areas. True, that’s where we need vegetation the most, and many species do especially well “getting in on the ground floor” of the restored ecosystem. But many other species (that will ultimately be the heart of the ecosystem) do not. As Dr. Betz encouraged for prairie plantings, we learned to withhold much of our finest (conservative) seed for what we came to call the “Turf Mix.” We first used that mix for former grazed-out pasture that consisted of thin stands of poverty oats, bluegrass, oxeye daisy, etc. Later we used Turf Mix in “settled down” restoration areas, ten or twenty years after the original planting.

What would be the equivalent for woods? From studying the literature and the sites where our fire pink seeds came from, it seemed like a good hypothesis that fire pink does best in the intense competition of diverse, short woodland conservatives. We had few such spots in Somme. We searched out the spots where some of the most demanding conservatives were doing well: hepatica, rue anemone, wild licorice, and the others mentioned above. We mapped those areas, thought about them, studied them. Then we invested our saucer of seed in the little spots that seemed best[9].

It is not our intent or hope that those spots will be the “final” home for fire pink. We expect plants (and whole communities) to move around over time (in response to droughts, fire, disease, and all else the ecosystem faces). Many areas are obviously becoming “more conservative” or “higher quality” or just “healthier” over time. A species that fits well in an area during one phase of the restoration process may not fit there years or decades later. But while it was successfully competing, that little population made tens of thousands to millions of seeds, and all those little embryos scattered themselves far and wide to prospect for new opportunities. Some species may thrive for a while and then vanish from the site forever. Fine. Others may wander as refugees from place to place and eventually find their perfect niches. That’s nature.

It will likely be years before we know whether or not we’ll be able to celebrate the success of fire pink at Somme. We’ll be sure to tell you when we find out.

PHOTO CREDITS
Fire pink by Carol Freeman
Hummingbird by Lisa Culp


END NOTES


[1] Many species have hovered in small numbers for years, only to explode decades later, often after considerable “intensive care.” For example, for the first sixteen years, the prairie white-fringed orchid never totaled more than ten plants per year. In recent years there have consistently been hundreds, indeed, more than any other site on the planet, and they’re spreading widely around the site on their own. A few of the others that have followed this “slow starter” pattern are eared false foxglove, savanna blazing star, Leiberg’s panic grass, and violet bush clover. Scientific names for the species just mentioned are, respectively, Platanthera leucophaea, Tomanthera auriculata, Liatris scariosa, Panicum leibergii, and Lespedeza violacea.  

[2] Aldo Leopold: “The last word in ignorance is the man who says of an animal or plant, "What good is it?" If the land mechanism as a whole is good, then every part is good, whether we understand it or not. If the biota, in the course of eons, has built something we like but do not understand, then who but a fool would discard seemingly useless parts? To keep every cog and wheel is the first precaution of intelligent tinkering.”

[3] Temporarily in that we keep few species there for very long. Our goal is to amass enough seeds to broadcast them widely so that they can find the niche that they’ll thrive in. Once they’re reproducing on their own in the natural ecosystem, we ruthlessly weed them out of the gardens and “nursery strip” to make space for the more needy.

[4] The 1915 charter of the Forest Preserves sets a high bar: “to restore and restock, protect and preserve the natural forests and such lands together with their flora and fauna as nearly as may be, in their natural state and condition.” With the advances of knowledge in subsequent decades, Betz, Eisenbeis, and others saw that mandate to be essentially “biodiversity conservation for public benefit.” In other words, our woodlands were for recreation, but a recreation that would preserve nature. It was increasingly clear that nature needed a lot of help if it were to be truly “protected,” “restored” and “restocked.” Even the healthiest remnants of woods and prairies, argued Betz, had been subject to grievous degradation in the years since European settlement (the 1830s for Somme). In respect for Betz’ influence, we all focused first on prairies, but soon wetlands, savannas, and woodlands were seen to need the same conservation efforts.

[5] For the first hundred years they lost them mostly to overgrazing by cows, pigs, and other livestock. Later they suffered even more from excessive shade, as lack of fire and an influx of invasive species stole their sunlight. In recent years, overpopulated white-tailed deer have become an increasing problem for some surviving species.

[6] Fire pink associate species (with their coefficient numbers in parentheses) are given below. None of them are “perfect tens” like fire pink. But the list below describes about as conservative classic woodland community as you can get: rue anemone (7), woodland fescue (5), wild licorice (7), shining bedstraw (5), hepatica (6), wide-leaved panic grass (5), woodland phlox (5), Jacob’s ladder (5), and bloodroot (6).

[7] To collect a rare seed like fire pink normally requires a bare minimum of two trips. Before the first one, try to determine when the plants are likely to be in flower. Then go there, find them, and mark them in some way (flagging, sketch map, GPS, whatever works). When fire pink is bright red, it’s easy to spot them. When they’re just green, finding a few plants in a big preserve is nearly hopeless. Next, try to determine when the seeds will be ripe. If you’re lucky you’ll hit it on your first trip. But more likely by your second trip you’ll find that deer or rabbits ate all the plants, or they were
Fire pink seeds are precious. What is all that dramatic ornamentation about?
Every new detail we learn has the potential to help us be better stewards. 

trampled, or a drought caused them to abort their seeds, or you waited too long and they just fell, clunk. In other words, this mission requires an investment of time. It’s work. And you can’t devote time to species A if you spend too much time on species B. So you prioritize. 

[8] Well, not exactly at random: we put them in the “wet-mesic” and “mesic” woodland mixes, and planted them with the rest of our seeds. One or two flowering fire pinks would appear, but they wouldn’t persist. (The species seems possibly, from my garden experience, to be short-lived plants.) More importantly, they wouldn’t reproduce and spread.

[9] We seeded our pinks in Somme Prairie Grove and Somme Woods Forest Preserves in accord with our approved plans. We tried to find open turfs of conservatives for them. Good luck, little seeds.

20 comments:

  1. Impatiens capensis is another species that is heavily used by hummingbirds in late summer. Seed collection of this species is fun. If people reading this comment have collected seed of Impatiens capensis then they will understand how it got the common name spotted touch-me-not.

    As you know, I collected seed of Silene virginica years ago. Pete Jackson spread the seed in an area where they would be likely to thrive after invasive species had been removed. However, I do not know if anything ever resulted from this effort. Maybe Pete will comment on the results.

    I have noticed that Silene virginica is partial to slopes. Consequently, I am not sure good habitat for Silene virginica is available at Somme.

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    1. James, thanks for thoughtful comments. How can you resist checking how those seeds you planted are doing?
      As for slopes, you may be right, but the stands I found at Deer Grove, Reed-turner, and Palos were all on fairly level ground, so it may have a variety of niches that work for it.

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    2. I checked the area where the seeds were sown for a few years afterwards, but I have not followed up recently. One of the problems is I only collected the seed and did not personally sow it. I am not sure exactly where to look. Stewards often insist on sowing seeds or planting plugs personally, or with a select group, which makes evaluating the results of my efforts very difficult.

      I think one of the reasons most of the Silene virginica plants I have seen are partial to slopes is because these areas have maintained a more open condition and the ground is less covered with leaves than the more level areas. I know Dale Shields established some plants from seed on less sloping ground just upslope of an intermittent stream. Dale likely was successful because the area where he sowed his seed was receiving management that was not yet occurring in other areas.

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    3. I noticed on my rural southern Tennessee gravel/chirt steep driveway, that a few of these “fire-pinks” are growing there along my side of the hill-driveway.

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    4. As Dr. Peoples suggests, this species may have differences from place to place, with varied adaptations and niches. For conservation strategics, they may be conserved in some areas as just another plant in the ecosystem, without any special considerations. But where they seem to be dying out, they may deserve special attention. Does that specialized population have genetic alleles that may be important in the future? No one can say without study. If we can save what's vanishing, without harming some other priority, perhaps it's a good idea.

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  2. A thought just came to me, regarding counting seed... In the microbiology world, counting bacterial colonies on an agar plate is among the most important, but most tedious tasks. so much so that there are numerous very expensive photographic counting machines...

    of late, with the ubiquity of the smartphone, lightweight free alternatives are becoming available. among them, https://itunes.apple.com/us/app/id620431249?mt=8

    I have no idea whether this will work for seeds, but it stands to reason that any reasonably small, granular objects against a contrasting background should work..

    let me know if you try it!

    -Byron

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  3. On my Southern Ohio property, Silene virginica is found in the floodplains of small, high gradient headwater tributaries. Associate species include most of those you listed as belonging to the conservative classic woodland community. Population numbers have remained relatively constant over the past 30 years. Except for the removal of invasives from the property, most of my management activities have been directed toward the more open prairies and barrens. Now that those areas are beginning to manage on their own, it may be wise for me to pay more attention to Fire Pink and its associates. Thanks for an interesting article.

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    1. Steve, I'd suspect that attention to fire pink in those headwaters would be interesting. I wonder if those floodplains need management beyond removing invasives. Are the trees oaks? If so, are they reproducing? Do you burn them?

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    2. The floodplains contain a mix of deciduous species and Eastern Red Cedar. Sycamore and Sugar Maple are common near the creek. Oaks become more common as you head up the slopes away from the floodplain. The oaks are reproducing and are rapidly increasing their numbers. They have no trouble becoming established in the open fields. When fallen trees create a woodland opening, I manually control competing maple and ash in order to give the oaks a chance to become established.

      In 30 years of management, I have not used fire on this property. My management techniques are tailored to private landowners who deal with limited time, finances and labor force. In Ohio, a landowner cannot legally just go out and burn his field. The burning laws require that any field burn be conducted by a trained burn team under the direction of a certified burn leader. The logistics and expense of conducting a burn under these constraints makes it impractical for a landowner to use this type of management.

      I am also not convinced that burning results in the maximum diversity of native flora and fauna in the type of habitats found in this area. What we have here is not the same as the expansive deep soiled prairies to the west. Burning our local prairie patches certainly changes the floristic expression on a site in a way that mimics the response to fire of an overgrown Northern Illinois prairie, but there are a number of species endemic to our local sites that are not found in the west. I have learned that many of these are intolerant of fire and are being eliminated from some sites. It has also not been proven that fire played an historical role in maintaining Southern Ohio prairies and barrens. Representatives from state agencies and conservation organizations have argued that I should burn, despite my apparent success in using other methods. I argue that since they are using fire on all of their sites, it is of little consequence if I exclude fire on my own small property.

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    3. I cannot imagine trying to manually control the maple and ash trees from over taking the oak forests in our local forest preserves and parks. For us the only economical way to maintain the ecosystem is by returning the historic fire regime.

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    4. Steve Wilson and James McGee both make compelling points about fire. Certainly it's valuable to compare a variety of management regimes. It would be so good to compare long-term studies of different management regimes for similar sites. People assume that "institutions" or "funded scientists" will do them. But often professionals have less ability to do "pure" and long-term ecosystem research than do plain, dedicated, curious individuals.
      I was actually impressed to hear from Steve that "Representatives from state agencies and conservation organizations have argued that I should burn." I can remember when little stewardship burning was done in southern Ohio. Thirty years ago there was strong prejudice against it from many. I'd love to learn more about what results have been, especially in the southern Ohio oak woods.

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  4. Thanks for sharing! This incredibly human story is so inspiring, and it brings me hope the we human beings can fulfill our own niche, just like the hummingbird.

    I performed a "visual calculation" of your photo, and I think you have between 4,000 to 5,000 seeds.

    One think I have heard about the pink family (and also the brassicas) is that these plant families eschew mycorrhizal association - implying they might tend to grow in microbially sparse soils. Maybe this plays some role in the eco-equation. It would be interesting to compare this aspect for the other associate plants you mention. Perhaps these woodland species also intermingle with tree species that foster a leaner microbiology? Juniperus, Juglans, Carya? Now I am purely speculating.

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    1. Michael, I appreciate your speculation because I know that you move from speculation to research and experimentation at the drop of a hat, or quicker. Let us know what you find. Many people suspect that some of the impressive patchy diversity of healthy nature reflects unseen patchy diversity of soil organisms.

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  5. When we lived in Indiana, we had a stand of fire pink living among a grove of chinkapin oak on a north facing slope overlooking a wetland. That site had outstanding spring flora diversity. We never burned it. It would a been a spotty burn at best given all the sugar maple, basswood and other tree species whose leaves don’t burn well.

    Contrast this to the site we now own in Wisconsin. The first spring after ownership was a huge disappointment as there was no spring flora! Now fourteen years later, we have outstanding displays of flowers all season long. All it took to turn it around was massive efforts with chainsaw and lots of fire.

    Thanks for the inspirational story Stephen!

    David

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  6. Cranberry Slough NP has moderate (more than 10 blooming individuals) populations in at least four locations. Most but not all on >5% slopes. Fire pinks respond positively to fire. The developing seed pods are eaten by deer, making collection of ripe seed difficult when deer present. At CSNP the species seems to be most successful near (in the shade of) barberry and honeysuckle.. A population of over a dozen plants had increased blooms after shrub removal but now seems in decline as species tolerant of more sun increase. Agree to James' addition of Impatiens as a humingbird favorite.

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    1. I'm interested. Do those slopes face in similar directions? Do the populations consistently stay in the same places for years? or decades? Do you happen to remember what plant associates the Cranberry Slough populations had?

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    2. The aspect of the slopes is not consistent. Two places has had a population for >12 years. A couple of locations are only known for 6 or less years (but I am not positive they are only that old.) The associates are not consistent. The Big Bend site is moderately weedy (Polygonum sp., common milkweed, Celastrus), but the Faber ridge site has conservative associates (Dioscorea, Anemonella, CAMSCI, PANLAT). Faber ridge is the slope that was brush cut in 2008 and saw the increase for a couple years but in last couple years has shown decreased abundance. I have seen SILVIR is flood plains along middle fork of Vermillion river and in rocky outcrops in IN (Portland Arch). I consider it's ecology mysterious, but was happy to find it does will in the limestone gravel which dominates my Hegewisch backyard. Two years ago I focused on SILVIR and this year I produced 30 g of seed in my yard. (Ripe pods were collected each day for about a week and then I cut all remainimng stems and let the pods 'mature' in a bag.) Most of that seed already return to FPCC, and time will tell if it generated new populations. Fire pinks are a beautiful species that adds immpressive color about the time of the solstice. Good luck with your efforts to generate healthy populations at Somme and other NB sites.

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    3. The largest populations at Deer Grove seem to be on ridge crests and clay slopes that become very dry in summer. Aspect seems less important than an availability of light and lack of heavy competition. However, I have not observed Silene virginica on the steepest Northern facing slopes which receive no direct sunlight. Silene virginica may be found with the rich assemblage of associates mentioned or be in rather depauperate situations of dry clay banks. Other interesting stations are individual plants along trails and at the edge of a clearing at the base of a tree that had tipped over. Like fire, floods, and dry conditions the last two situations had some disturbance that limited competition and increased available light.

      Rather than immediate associates, what is likely most important for Silene virginica is an abundance of species that bloom throughout the season which support a healthy population of hummingbirds.

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  7. This:
    >3. They interact with other rare species to consolidate a conservative turf.

    is a really interesting thought that I can't remembering seeing expressed directly here.

    It gives me a better sense of the potential resilience of these seemingly fragile ecosystems, but they may need to be (re)made whole first.

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