I am Sibylla Brown. I was born in Germany in 1940. In 1946 my father, a German Operation Overcast scientist, was brought to the U.S. My family followed him to the U.S. in 1947, settling in Cedar Rapids Iowa in 1950. I married my husband, Bill in 1962. Bill practiced dentistry in Des Moines for over 40 years. In 1993 we sold our house in Des Moines and moved to a 200 acre farm in Decatur County, Iowa. Except for a small vineyard we had no plans to farm our land. But we did want to take care of it, particularly the overgrown oak and hickory woodlands. We began timber stand improvement in 1993. When we learned our land was actually a rare oak savanna remnant we implemented prescribed fire. These posts share how we found the land and how we made the transition from city-dwellers to country folk.
(This growing season Bill and I are documenting as many breeding resident butterflies and moths as we can find and identify. In order to assess how our prescribed burn impacts the Lepidoptera we are comparing the Timberhill collections to what we find on adjacent unburned woodland, wetland, and meadows. This will not be a list of all the species we see. It will be our observations of habitat sensitive species that spend their entire life cycle here. Neither of us is an expert lepidopterist but we hope to learn by doing. We identify our specimens by referencing various field guides and websites such as Insects of Iowa.)
The Timberhill butterfly season began on March 30, a sunny and breezy day with the thermometer reaching 72’ F. , when Bill and I saw a mourning cloak, a breeding resident that overwinters as an adult. He flew out of the managed woodland east of the trail as we walked south through Butterfly Alley, the trail that separates our southeast woodland from the neighbor’s unmanaged woodland. Broad and sunny, Butterfly Alley is always a good spot for butterflies, especially in early spring.
Our next sighting was on April 11, another warm and sunny day with 73’F. Pairs of spring azures flew overheard while single specimens settled on the rue anemone and spring beauty blooming east of the trail. Near a clump of gooseberry bushes bordering the unmanaged woodland we saw a gray comma. Another breeding resident this species also overwinters as an adult. I saw another specimen in the Timberhill south meadow the following day.
It was April 29 before we saw the first skipper – a Silver spotted skipper on the south portion of the trail with unmanaged woodland on both sides. As we walked north we saw a Juvenal’s duskywing perched on a dead plant stalk at the edge of the unmanaged woodland. Juvenal’s is an uncommon breeding resident of open oak woodlands and adjacent areas. (Oak is its larval food source.) Further north was a Common sooty wing, a common breeding resident.
The rest of the week we moved our butterfly search to Timberhill. We had seen silver spotted skippers there but would we find any Juvenal’s duskywings? We began our search in the prairie just south of the Hickory Grove. Like all of our prairie openings it is surrounded by mixed oak-hickory woodlands. On May 6 we saw four Juvenals and one Silver spotted skipper in this prairie remnant. Despite intermittent rain and strong wind gusts we saw two Juvenal’s and two silver spotted skippers in the east savanna ridgetop oak opening on May 7. We found a similar pattern in the Hidden Prairie where we saw four Juvenal’s and one Silver spotted skipper on May 8.
Our last sighting of the Juvenal’s skippers was on May 13 in the East Savanna ridge top. Bill noticed movement among the scrub oak in the center of the oak opening. Carefully Bill stalked and netted one of the specimens so we could identify the species. Instead of one specimen we found two Juvenals in the net. When we released them one settled on an oak leaf in front of us and the other flew swiftly away. A mating pair? Was she was laying her eggs in the scrub?
As we headed back to the house a giant swallowtail flew swiftly overhead. The summer season is about to begin.
Brock, Jim P. and Kenn Kaufman, Butterflies of North America.
Schlicht, Dennis W., John C. Downey, and Jeffrey C. Nekola, The Butterflies of Iowa.
In January 2009 there was a discussion on this list serve of the decline of habitat dependent invertebrates on Iowa prairies. Dennis Schlicht’s s “Prairie Paradigms “ paper* was specifically noted. I disagreed with paradigm 5 that “invertebrates that reside in any life stage above the ground do not survive dormant season fire.” Although we use dormant annual fire to manage our restoration we have not found this to be true of ants, native bees, or beetles. Lists of these invertebrates that were compiled here by experts include not only habitat dependent species but several Decatur County records as well.
In that discussion I was strongly criticized after I wrote a post expressing the belief that annual dormant season fire leaves much invertebrate habitat because the fire is always going upward, “burning the fine standing fuels of the season.” I also stated that annual burns such as we conduct are much less destructive to habitat specialist invertebrates than occasional burns. In annual burns the fire is always going upward scudding through the fine fuels of the season. It leaves a patchwork of burned, partially burned, and unburned ground.
It didn’t take long for someone to respond that that “insects, eggs, or immature stages within the plants and the thatch cannot survive such a burn regimen.” My chief critic then asked me, “What skipper species were there before you started burning? Are they still there? You are conducting a scientific experiment-burning an ecosystem which has been unburned for years-without a control.”
I am not a scientist nor are Bill and I conducting a scientific experiment at Timberhill. We are simply landowners who have learned that fire is the most effective means of restoring the overgrown woodlands, prairie openings and wetlands on our 200 acre property. Ever since that discussion, however, I knew that I would have to document the Timberhill Lepidoptera and determine how our fire regimen impacts them.
That is easier said than done. In 2009 I could recognize the common butterfly species but knew nothing about skippers and other habitat dependent species. Thanks to the kindness of a couple experts I have since learned to identify more species. And there are numerous Internet resources such as the Insects of Iowa website and the Iowa Insects list serve when I need help with identification. I have also found two lists of Decatur County butterflies. So during 2015 growing season Bill and I plan to identify as many Timberhill Lepidoptera as possible. And we have permission from a neighbor who has neither burned nor thinned his woodland and prairie to look for butterflies on his property.
One of our favorite butterfly spots is a trail we call butterfly alley. It is where we always see the first mourning cloak of the season, where spring azures flit through the spring ephemerals and tiger and giant swallowtails glide among the treetops. The trail separates our southeast woodland from the unmanaged adjacent property. The two photos above demonstrate the difference in ground cover ephemerals between the burned and unburned woodland. This is where we will begin our survey.
*Dennis Schlicht, Iowa Lepidoptera Project, 1108 First Ave. Center Point, IA 52213 (First Presented in public lecture in Iowa City, IA on October 3 1993
April is birthday month at Timberhill. Our son Alex and I were both born in April. It has become our custom to combine our celebrations on the same day. This year our celebration coincided with the beginning of the morel mushroom season.
A choice edible these fungi have a limited season, fruiting for only a few weeks in April and May. From early April I watch for the signs that morel season is about to begin. I listen for the constant singing of the tree frogs, watch for the first asparagus spears in the vegetable garden, for the leaves of the silver maple trees to emerge, and the mayapple leaves to open. When the woodlands are fully carpeted with spring beauty, trout lilies, toothwort, and other spring ephemerals I know the time is near.
We never know where the first morels will fruit. Will we find them under the dead cottonwood in our West Creek unit? Or under the silver maple and elms along Brush Creek? In 2011 we harvested early morels in the hickory grove west of our house. Last year we also found them associated with river birch in the West 40. The only sure thing about morels is that they always surprise us.
On April 16 Bill and I found the first specimens fruiting in a patch of mayapples in the hickory grove. But we waited until April 18, the day of our birthday celebration to harvest them. Our sons Chris and Alex were both here. After a breakfast of fruit compote and asparagus and mushroom frittata we walked to the hickory grove and harvested twelve yellow morels fruiting there. (After the first morels appear it usually takes another week for the main crop to fruit.)
We began our birthday celebration dinner with a fresh asparagus appetizer and Champagne J. Lasalle. For the main course I combined the fresh morels with reconstituted dried morels (from last year’s harvest) in a pan sauce for veal chops. We served the the veal chops smothered with morels and pommes de terre macaire. To accompany our spring feast Bill poured a bottle of Saint-Romain Cote d’Or burgundy wine.
My guardian angel must have been looking after me on June 1, 2003. That’s the day that Wayne Peterson and Chris Bair brought Gerould Wilhelm to Timberhill. In the ten years since my husband Bill and I began actively restoring our property we had been searching for someone to advise us. We wanted to know what the mosaic of savanna, open woodland, prairie, and wetland that comprised our property should look like. We attended field trips sponsored by the Iowa Prairie Network, Iowa Native Plant Society, and other groups but nothing we saw looked like Timberhill. We could find no models to emulate.
We also attended prairie and savanna restoration workshops. There we learned that we were not following accepted practices: that we should be burning every three to five years, not annually, that we should stagger our dormant season burns with spring and summer burns, and that we should be planting oak savanna indicator species. We should also be herbiciding non-native plants.
Yet our experience contradicted this dogma. Annual fire was restoring our landscape. Conservative plants were out competing the less conservative. Fire had even restored the yellow lady’s slipper orchids and round stemmed false foxglove. Countless red-headed woodpeckers, a species threatened by habitat loss, had made Timberhill their home. And multiflora rose was dying.
On May 10, 2003 I sponsored a native plant society field trip to Timberhill. Wayne and Chris made the trip from eastern Iowa. They liked what they saw and asked if they could come back with Gerould. The three of them returned on June 1, 2003.
As we meandered through the East Savanna where leadplant, purple milkweed, and prairie coreopsis were just coming into bloom and admired the yellow lady’s slippers clinging to a steep hillside in the south east woodland Gerould wrote down all the plants he saw. I found out later that he noted 206 native vascular plant species that morning. This compared with the best natural areas in Illinois, Indiana, and Iowa.
After the East Savanna meander we drove through the W40 in our utility vehicle. As we followed the trail through the white and bur oak savanna Gerould looked around and said, “Nobody’s doing this kind of thing.”
After we sat down to lunch I was able to ask my questions. “I’ve been told that we shouldn’t burn annually. That we’re doing irreparable damage to the invertebrate community.”
“You’ve got to have fire because fire is what sustains the ground cover matrix. If you look when you burn annually at the scale of an insect, the scale at which they are most likely to be found, the fine fuel is held elevated above the ground. Annual fires are fires that scud, not like the grinding, parboiling occasional fires. The available fuel is always above ground and the heat is always going upward. So the most salubrious circumstance for this woods is to every year burn during the dormant season. That will leave thousands and thousands of unburned patches on the scale of an ant or a beetle.”
“Should I do more thinning? How will I know that enough light is reaching the ground?”
”The plants will talk to you. They will tell you. As long as you’re burning and your biota is coming back and sustaining and you see fecundity it’s okay.” He explained that no one knows what the optimum canopy density should be. “You can have a closed canopy of bur oak get all the light you want. Ecologists come up with a kind of archetypical theory of a savanna and then say this is how a perfect savanna looks. And then they manage towards that goal when it has nothing to do with goals. It’s what is here. The template that’s present. Just study the thing as you have it before you.”
“What about the non-natives? Should we be spraying them with herbicide?”
“The weeds will give up. They will be outcompeted by natives.
Three months later he returned with biologist Laura Rericha. Not only did Laura know all the plants, but she was also an expert ornithologist and noted authority on Midwestern ants and native pollinators. On her first visit to Timberhill she recorded 22 native ant species, an exceptionally high number in a single plant community. I was determined to have them back. Here finally were two people who could tell us what we had and how best to manage it. These were the experts Bill and I had been looking for.
Through the Southern Iowa RC&D we applied for an EPA grant to study the impact of annual fire and thinning on the birds, ants, and vegetation of the remnant woodlands at Timberhill. Our application was accepted. The Wilhelm-Rericha Timberhill report can be found here.
A psychologist once told me that my biggest failing is my inability to see the forest for the trees. Working with Laura and Gerould made me see the forest and realized that our focus should be to document as many flora and fauna as possible. Thanks to Laura and Gerould the Timberhill species lists now include 460 vascular plants, 43 native bees, 57 ants and 86 birds. In 2010 & 2011 Edwin Freese collected beetles and stoneflies adding many more species. Bill and I are currently documenting the butterflies and moths. Anyone out there who would can show me how to find the salamanders?
Over the next three years Dan and Vicki thinned the remaining woodlands and Bill and I continued our prescribed burns, burning most of the east woodland, the prairie openings, and the lower fields each winter. Each successive burn doubled the effect of the previous fire increasing the ground layer plant cover. Fire was maintaining an open midstory, controlling resprouts, stimulating expansion and reproduction of herbaceous plants, and providing germination sites by removing surface litter. As the land continued to heal we were overwhelmed by the natural beauty unfolding before us.
From early spring through late fall there was continuous bloom in the savanna, open woodland, and prairie openings. The growing season opened in late March when rue anemone, bloodroot, and trout lily came into bloom. Virginia bluebells and wild geraniums cascading down moist woodland slopes soon followed. In May hundreds of wild hyacinths and cream wild indigo indicated that spring ephemeral bloom had reached its peak.
June became the month for orchids, milkweeds and butterflies. Large clusters of purple twayblade orchids, strong indicators of a healthy, fully functioning ecosystem, bloomed on every ridge. Even the yellow lady’s slipper orchids bloomed again on the steep moss covered hillsides of the southeast woodland. (My neighbor told me that they hadn’t bloomed since 1925.) Purple milkweeds at the woodland borders were covered with great spangled fritillary and swallowtail butterflies ingesting the sweet nectar. Monarchs nectared and deposited eggs on patches of common milkweed in the south meadow and old fields. Leadplant, pale purple coneflower, and coreopsis completed the June tableau.
July brought scaly blazing star, clumps of blooming June grass, and many colorful ectomycorrhizal fungi including bright red Russulas, yellow Amanitas and blue indigo milky caps. If rainfall continued a variety of bolete mushrooms began fruiting two to three weeks after the gilled fungi. Even on hot, dry summer days one could see the plants respirating, as fine morning mist rose through the open woodland. Plants flourished in dry weather because they were now able to tap into the ground water stored in the rich porous soil. White prairie clover, slender and violet bush clovers, and rough blazing star looked fresh despite the heat and lack of rain.
Fall became the season for false foxgloves including the rare round-stemmed false foxglove and yellow false foxglove. As the temperatures dropped and plants became dormant the delicate sky blue asters signaled winter to come.
Yet we were uncomfortable with the changes. Logic and reason told us we should be controlling/managing the changes. But the changes weren’t logical. There were only lots of surprises. On our daily walks Bill and I often found wildflowers blooming and mushrooms fruiting in unexpected places.
The hard edge of wild plums and hawthorns that had separated the woodlands from the grasslands disappeared, the difference between prairie and woodland becoming less distinct as they coalesced. The land had become a mosaic of heterogeneous plant communities that melded into one another. One certainly couldn’t tell the difference by looking at the plants. Prairie species such as big bluestem were becoming established in the dappled sunlight under the oak trees. Even rattlesnake master, leadplant and blazing star bloomed on the wooded ridges.
Our forester wasn’t much help. On a spring visit after our third burn he looked at the bright green carpet of pen sedge that carpeted the woodland floor and exclaimed,
“Grass! You’re not supposed to have grass in the woods.”
I told him about our prescribed burns. “You should never burn woodlands. Burning can ruin a good woodland. You’re perverting reproduction – fire will kill all the saplings. Besides, it’s too hard to control and you might burn down some valuable trees.” After that visit he began sending “Smokey the Bear” fire prevention leaflets with his annual report.
But we persisted. Annual dormant season fire had become our primary management tool. As long as the diversity of mushrooms, plants, and birds increased each year we were content. With no background in restoration ecology we were hesitant to do more and settled for whatever regenerated from the seed bank and suppressed plants.
As Gregory Cajete advises in his book, Native Science: Natural Laws of Interdependence, “Intervention in a natural process is taken on only with great care and much consideration. Continual emphasis is placed on ‘being of nature’ or working with its natural flow; listening and looking closely are consistently practiced.” (p. 65-66)