Sunday, August 06, 2017

Somme Prairie Grove tour: Early August

The Somme ecosystem explodes in mid-summer. Back in early July, the vegetation was rich, but compact. Before we look at today's photos, let's look at two from mid July:
July 10: the flowers and grasses were mostly knee-high.
In bloom here: butterflyweed, leadplant, wild quinine, and black-eyed Susan.


July 28: the gayfeather (spiked blazing star) is in full bloom with rattlesnake master, Culver's root,
and sweet black-eyed Susan - all twice as tall as the flowers on July 10. But the explosion is just starting. 

The points discussed below:
Point 1. On August 6, the big bluestem grass is well over the head of co-steward Eriko Kojima.
The blazing stars, Culver's roots, and rattlesnake masters are well down underneath the grass. 

Point 1 
A month ago, the prairie grasses were up to our waists. Today in some places, they’ll be well over our heads. The main tall grasses in this section will be big bluestem (turkey foot top) and switchgrass (delicate, wide-spreading heads).



Point 2 
Bright ribbons around trees here show where the Illinois Natural History Survey and Forest Preserve District staff are studying Somme Prairie Grove as a model for the Next Century Conservation Plan
This area has too many pole trees. (More and better woods photos later.)

Point 3 
Seeds are forming on some of early-season bloomers. Notice here, seeds from New Jersey tea, white false indigo, meadow parsnip (Thaspium), and golden Alexanders. 
We’ll soon gather, prep, and broadcast these seeds to spread them to needy areas.

Point 4 
Our youngest ecologist spotted a snake sunning in the bush here. Good job, Cormick.
This is a good place to look at the major habitats at SPG: thickets (here), prairie-like openings, woodlands, savanna, wetlands

This thicket is becoming more “natural” through a lot of work. Is that "gardening" or ecological restoration? We discuss.

Think about this area: 2,000 years ago. The bison and wolves were in the prairies. Deer, elk, and mountain lions were mostly in the woods and savannas. The bison prefer the prairie because they eat mostly grass. The deer in the summer eat mostly wildflowers; in the winter they eat mostly the live bark of twigs (browse). The elk ate all those categories.

Point 5 
Parts of Somme have been utterly degraded, ecologically. This area was clear-cut and plowed. All the trees are young. But many species survived in nearby remnants (like the woods edges we've just passed though and the too-wet-to-plow swale edge just north of us). So when the Forest Preserve District bought the land, the species of these remnant areas started to spread. Later the stewards brought in seed of the species that hadn't survived here.

The historic larger trees in this savanna were mostly bur oaks. Today the trees in this disturbed area are mostly scarlet oaks. That's because the scarlets are dispersed over distances by blue jays. (Heavy bur oak acorns aren’t. Squirrels disperse these bigger, heavier ones. But squirrels don't venture far out into the prairies or pastures. Thus, bur oak doesn't get restored by squirrels until other trees are established -to serve as highways for the squirrels.) But bur oaks are needed here. They are the heart of the savanna. They have the thick bark that withstands enough fire to make the savanna. We already see the thinner barked scarlet and white oaks being burned down. So we help out the recovery of the few bur oak saplings that we do find (see below), and we help the squirrels move acorns.
The bur oak “recruits” you see here were protected from the deer in cages until they were tall enough to escape (both mouths and antlers).
More basswood here should be cut, but we didn’t want to lose too much shade too early.
Distinctive plants here: starry campion, Kalm’s brome, pale Indian plantain.
Note the cage that helped this bur oak get tall enough to be above deer browse height.
 The controlled burn this spring was hot enough to "cook" its finer branches.
But, despite natural setbacks, this tree is vigorously becoming part of the structure of the savanna.
Don't be impatient, just give it one hundred years or so.
In this area, notice many caged oaks and many more un-caged burned scarlet and bur oaks down in the grass. Re-sprouting, burned-off oaks are a natural part of the savanna. 

This is one of the areas where Forest Preserve staff ecologists have been collecting scientific data.
To the left is Deborah Antlitz, and to the right is Monica Mueller.

The data will help set standards for more ambitious restoration initiatives. 
Point 6. Summit: Coyote Knob – good and gravelly reminder of the glacier. This gravel hill was deposited here by the glacier - about 12,000 years ago.

In the cages are now-rare prairie gentians (which need protection from deer and voles if they are to make enough seed to recover their numbers).

In bloom here also is: Solidago (or Aster) ptarmacoides. It it an aster or a goldenrod? Scientific knowledge of the ecosystem is so rudimentary that we haven’t even known which genus to put this plant into.

Our endangered “slender wheat grass” and "bearded wheat grass" (very tall and thin grasses, both of which we've been seeing along the trail) have recently been re-classified twice. A few years ago they were a wheat (Agropyron). When they were made an Illinois Endangered species, they were re-classified as a rye (Elymus). Anyone hungry for rye bread? Then the new Flora of the Chicago Region announced them with a third genus (Roegneria).

We humans know the moon’s geography better than the floor of Earth's ocean. Similarly, our knowledge of space and particle physics has increased vastly more rapidly than our knowledge of the ecosystem. Space has military implications. The ecosystem doesn’t get that kind of attention – though it’s so much more crucial to our lives, futures, and peace. Just a thought.

As we enter the stretch of trail shown by a dashed line of the map, we’ll walk a trail maintained only by feet. Experience the savanna wilderness.

Point 7. The Party Spot: this little area has a great history. When we first started restoring this site, it was littered with old car seats, milk crates, vehicle tracks, and beer bottles and cans. It was a teen party spot. All around it were dense invasive trees and brush. After we cleaned up  and thinned the brush, it was a pretty opening, and we began to notice many rare plants surviving here. It was on the edge of an old fence line, and the "partying" kept the brush at bay to some degree (by trampling and cutting wood for camp fires). That actually helped preserve some species - like the threatened small sundrops, shooting star, violet wood sorrel, poverty oaks, etc. It seems likely that it was open enough to be picked as a party spot because the soil had eroded away.  Thus, it had both challenges and surviving ecological riches. We scattered seed, and it is now one of the botanically richest areas - in part perhaps because the brush never killed off the turf and its soil biota.  

Point 8. Cross the Central Swale again. Notice three more-or-less distinct bands of vegetation:
In the swale (wet prairie): cord grass, sedges, swamp milkweed, Indian hemp, blue vervain
Next band (wet-mesic prairie): saw-tooth sunflower, Culver’s root, big bluestem, switchgrass
Next band (mesic prairie): little bluestem grass, dropseed grass, leadplant, prairie clovers, bush clovers

A beautiful but strange (and temporary?) woods. See below. 
Point 9. The woods along the western edge are all artificial in that the trees consist entirely of invaders and inappropriate species planted long ago by Forest Preserve staff - before restoration and conservation were well understood. Some of the planted trees were birch, pine, black locust and other non-savanna species, which we removed decades ago. But many of the planted trees were white oaks. White oaks are "natural" and make "ecological sense" on the east side of the moraine here. But this area was originally the openest part of the prairie and savanna border - with the only trees being bur and scarlet oaks. When restoration started here, cutting down all these big old white oaks seemed like a lot of work - and a low priority, compared to other needs. So we've restored this area with the understory grasses and wildflowers of woodland – for now. 
Highlights in bloom now (all planted by us): woodland sunflower, Joe-Pye weed, starry campion, bottlebrush grass, wide-leaved panic grass, long-awned woodgrass.

Point 10. Prairie swale. There is remnant prairie here, but the wetland is artificial - its wetness resulting from the railroad making a dam here.

One of our many mistakes and disappointments, as stewards, is that the original prairie here was neglected. We thought a conservative approach was best. We should mostly leave it alone, we thought. That turned out to be a mistake. Over forty years, while we weren't paying as much attention as we should, it lost much of its quality to shade of the slowly growing white oaks and brush. The oaks, brush, and artificial wetland (dammed by railroad) discouraged fire. The prairie remnant here needed more care; without it, its richness declined substantially. Now it’s getting some of the help it deserved.

Point 11. Southwest Meadow.
Very beautiful – at this time of year – at this stage of its restoration. This open meadow was solid buckthorn and ash with understory of bare ground. It was formerly prairie. The oak savanna started up hill, where the morainal slope begins, according the the 1839 Public Land Survey. We had some group workdays here, but most of the brush was cut in the summer of 2008 by Rett Donnelley who was looking for a new job in the mornings and expending his excess energies on buckthorn in the afternoons.

Point 11. Grasses among the flowers: cord grass, switchgrass, and Canada wild rye. Hard to make out? See discussion below.
Wildflowers here include ironweed, sweet black-eyed Susan, gayfeather, and rattlesnake master.
The grasses are the foundation of a grassland ecosystem. Every quality bit of prairie or savanna is thick with them. The wildflowers catch your eye first. But the elegance of the grasses sneak up on you. In this photo you can just make out a cord grass head (to the right of the two dead tree trunks); a long leaf of cord grass arches away from it to the right. Canada wild rye can be seen as a shaggy green head arching under the cord grass leaf (and seeming to come out of a purple ironweed head). The arcing grass leaves are symphonic in grace and complexity.

Switch grass is even more obscure here, yet covering most of the photo; it's the little reddish brown dots everywhere. If you can expand this photo, you can get a look at the structure of switchgrass head against the dark trees in the upper left - just above another purple iron weed.
Point 11. A wrecked elm (left) and basswood (right) remind us that the former, dense pole buckthorns
and other invaders are doomed as nature recovers here. 
We saved some of the elms and basswoods. But over time, they're not making it. Why did we save them? In part because cutting them would be too much work for too little reward. We had more important work to do. Also, dead elms makes great woodpecker, and they mostly die before too long from Dutch elm disease. The basswood was huge, with five of six substantial trunks. All of them were gradually blown down except the skinny pathetic pole on the right. The bushy mess on the left is trying to recover; the top two thirds of a big trunk was snapped off by wind. Pole trees are often blown down when the supporting other pole trees are cut away.

This area was originally the edge of the prairie that stretched from here to the horizon. The savanna started fifty or a hundred yards or so to the east, where the morainal slope starts to rise. An argument could be made to restore savanna here. A little patch of restored prairie wouldn't amount to much here, as there is no prairie adjacent, and the savanna would be more sustainable for its animals (and for many ecological processes including the evolution of plants to adapt to changing conditions) if it were bigger.

On the other hand, an argument could be made to restore prairie - if the Somme Prairie to the west could be expanded this far. That however would be a long time from now, if ever.

The dense patch of willow aster in the foreground of the above photo is a reminder of our indecision here. We planted little seed, as we didn't know whether to restore as "prairie" or "savanna" - and we didn't want to waste precious seed. Interestingly, the willow aster - a quality plant - is taking over from the weedy tall goldenrod that was dense here for the first few years after cutting the brush. The quality plants that are gradually taking over in this area help us decide what else to plant now.  
Point 12. Big old limb, bigger than many whole trees, stretches west from the edge of Vestal Grove.
It once stretched over pasture, but perhaps not the prairie that preceded the farm.
The much larger original prairie fires would have burned it off. 
Point 12. Stepping into Vestal Grove

Big old bur oaks. Some with huge limbs reaching out to the west. Probably not a feature of the pre-European times, but a feature of pasture, after the fires stopped. (Are those limbs 200 years old, or 100, or what. (Please don’t saw one off to count the rings, but when those trees die, I hope somebody counts the rings.)

One of the best (and one of the world’s first) restored oak groves. Probably was originally savanna rather than the woodland it’s been restored to. But the original savanna is on its edges.

People think of woods as having a spring flora. Most people don’t know that woodlands once had a rich flora all season long. There are distinct floral seasons, all rich with wildflowers, grasses, and sedges:
Early spring (toothwort, spring beauty, trout lily, false mermaid), late spring (trilliums, bellwort, rue anemone, starry false Solomon’s seal, wood betony), early summer (wild hyacinth, golden Alexanders, Solomon’s seal, wild columbine, doll’s eyes), late summer (tick-tre-foils, woodland sunflower, Joe Pye weed, starry campion), early fall (zigzag goldenrod, elm-leaved goldenrod, Short’s aster) and late fall (elegant seeds and leaves).

Of course, there are whole different seasonal lists for the savanna and prairie, and whole different lists for each of those shade categories according to wet, wet-mesic, etc. There are currently 486 “native species” known from this site. A study of the diversity and conservativeness of the herb flora of Vestal Grove shows that it has been increasing in quality since 1985 and is still increasing today. No one knows how high the scores might be expected to go.

The wildflowers, butterflies, and birds of Vestal Grove are getting more diverse, year by year.
And the prairie, savanna, woodland, and wetland increasingly blend seamlessly into each other. 
Point 13. In the middle of the woods. Here a wet woodland swale runs through it. Don't think that "wetlands" are something different from prairies and woods. There are wooded wetlands and prairie wetlands.

Point 14. Cages are protecting two species of rare plants on this last part of the trail. Please don't knock them over.


The three sections of the tour were led by Eriko Kojima, Linda Masters, and Stephen Packard. Thanks to all participants for joining us and contributing questions, insights, and spirit.

If you'd like to review the July 9th tour of this same area, you can find it at:
http://woodsandprairie.blogspot.com/2017/07/july-9-2017-restoration-tour-of-somme.html

LIST OF THE PLANTS WE SAW ON THE TOUR 

This list gives the common names names of plants - only the first time we see each species. 

Plants at Point 1: wild bergamot, mullein foxglove, yellow giant hyssop, riverbank rye, Virginia rye, bottlebrush grass, sweet black-eyed Susan, purple Joe Pye weed, figwort, blue lettuce, white vervain, wild coffee (no flowers, but people ask about the big green seed capsules).

Plants as we go north from Point 1:
Starting in the wet-mesic prairie: gayfeather, rattlesnake master, big bluestem grass, narrow-leaved mountain mint wild qinine, compass plant, Culver’s root, winged loosestrife, rosinweed, switchgrass, nodding wild onion, prairie dock, early goldenrod, grass-leaved goldenrod.

Plants on the first rise (mesic prairie): purple prairie clover, rigid goldenrod, daisy fleabane, dropseed grass, yellow coneflower, common St. John’s wort.

At the edge of the woods: woodland sunflower and ironweed.

As we walk through the woods: starry campion, woodland brome (in seed), cowbane, forked aster, white grass, dotted St.John’s-wort, purple giant hyssop.

Point 2: No new species, great masses of woodland sunflower and purple Joe Pye weed.

As we exit the woods: smooth tick-trefoil, red-top grass, showy tick-trefoil, heal-all.

Point 3
Focus here on seeds: Note them forming on New Jersey tea, white false indigo, meadow parsnip (Thaspium), and golden Alexanders.
New species in bloom here: Compass plant and leadplant.

Plants in bloom as we walk north: flowering spurge

Point 4: No new species.

Walking west from Point 4: cream gentian and savanna blazing star (both only in bud), milk vetch, round-headed bush clover, wild carrot, pale Indian-plantain, bearded wheat grass.   

Point 5: starry campion, Kalm’s brome, pale Indian plantain.

As we cross Central Swale (a flowing stream after rains): water parsnip, winged loosestrife, wet-prairie obedient plant, cordgrass, mad-dog skullcap, Virginia mountain mint.

On the little rise we call Coyote Knob: stiff white aster (or goldenrod), butterflyweed.

(Here we start skipping points – if there are no new species in bloom.)

Point 8. Again crossing the Central Swale – this time on the west Inner Loop.
Notice three distinct bands of vegetation:
In the center of the swale (wet prairie): cord grass, swamp milkweed, Indian hemp, blue vervain
Next band (wet-mesic prairie): saw-tooth sunflower, Culver’s root, big bluestem, switchgrass
Next band (mesic prairie): little bluestem grass, dropseed grass, leadplant, both purple and white prairie clovers, round-headed bush clover.

Point 9
Here the woodland sunflower, Joe-Pye weed, starry campion, and bottlebrush grass are joined by wide-leaved panic grass, long-awned woodgrass, and silky rye grass.

Point 10
Obedient plant. Turtlehead. Prairie loosestrife, jewelweed.

As we go south from Point 10:  
False sunflower (or “ox-eye”) and wood reed.

Then in a very lightly wooded semi-open area:
Great blue lobelia, white snakeroot, water hemlock, spotted Joe-Pye weed, manna grass. Then ahead, under the white oaks: blue lettuce.

Point 11
Cardinal flower, cut-leaved water horehound, Canada rye grass.

Point 13
Woodland obedient plant.

In the thickets as you emerge from the woods: hedge bindweed, fringed loosestrife, elm-leaved goldenrod.

That’s a lot of plants. Enjoy as many as you can!



3 comments:

James McGee said...

Do you think of savanna which receives periodic fire as being at an equilibrium (climax community) or in a constant state of flux (succeeding to woodland or prairie then back to savanna)?

Stephen Packard said...

Well, James, I don't know if you'd find my perspective helpful. All communities that are "fire adapted" or "fire dependent" seem to go through cycles, long term and short term, and at varied spacial scales. Any "equilibrium" they may have must take into account the fact that trees grow and die and thus change the habitats for all the other species.

As trees grow bigger and wider, of course, shade-adapted species spread. As trees die, blow over, or burn up (wholly or in part), light-dependent species increase. If there area is a big and diverse one, there may consistently over the millennia be enough habitat of the three types you mention that all species survive, evolve, and move around as conditions change. You could say that the "fire climax" versions of these communities achieve stability within a dynamic complex.

For another example, during a few years (or decades) of cooler than average fires, shrub thickets may expand, with the gradual build-up of shade decreasing (or locally eliminating) some plant and animal species while increasing habitat for others. Then a very hot fire top-kills all the shrubs, and the species that need the shade are much diminished or eliminated, locally. At that point, perhaps for a period of years or decades, fires burn through the former thicket area annually, top-killing the surviving shrubs, and the species of open grassland increase. Various factors may result in a long term prairie at this spot, or thicket, or savanna, or woodland. If a given thousand acres for millennia had all those communities - and supported species adapted to each - then the goal for conservation might be for all to continue. It might or might not be part of a needed dynamic for the communities to move around the map a bit (thus requiring successional processes before some species could compete in a new place).

Hmmmm. I thought perhaps I could write something helpful in a quick blog response. Perhaps not? I do agree that there are interesting questions here. I am concerned that definitions might get in the way of thinking helpfully about those questions. In the short run, for me, the most important concern is that we conserve as many as possible of the diverse species of these ecosystems in all their forms (with all their alleles). The more we're able to do that, the more we can learn about these systems over time.

James McGee said...

Considering your comment about squirrels not venturing far out into prairies, I thought you might find the following photo amusing.

https://plus.google.com/u/0/photos/photo/107874019080399894118/6452008491712372130?icm=false