Nachusa’s small creatures help citizen scientists monitor stream quality. Collection, identification, and a tally of macro-invertebrates from the local streams are used as an indicator of stream health. The monitoring is done through a statewide program called Illinois RiverWatch, established to help determine stream water quality throughout the state and provide a warning of potential problems. At Nachusa, the program was started in the spring of 2014 before the bison arrived, so RiverWatch is not only used to monitor stream health, but also to help identify changes due to their introduction. This is the fourth year collecting RiverWatch data in three Nachusa streams: Wade Creek, Clear Creek, and Johnny’s Creek.
Illinois RiverWatch trains citizen scientist volunteers to collect, identify, and preserve important indicator species of macro-invertebrates found in streams throughout Illinois. Macro-invertebrates are invertebrates large enough to see with the naked eye. Examples include insect larva, snails, and aquatic worms. One person in the stream monitoring group is required to have the eight-hour RiverWatch training class; four hours in the classroom and four hours hands on in a stream. At Nachusa, we are fortunate to have several trained monitors and interested volunteers lead by Mary Vieregg. Others that often join in the fun are Cindy Buchholz, Mary Meier, Jan Grainger, Matt Friberg, Tim Ngo and myself. Interested people who have not been trained by RiverWatch can participate in the stream monitor with a trained lead.
A site is selected and the locations are documented and approved by RiverWatch. The same site and locations are used each year, so changes from year to year and over time can be observed. At the site, the first step is to mark off the sampling area with flags 50 feet and 100 feet upstream and downstream from the selected site. Then, a map is sketched marking stream contours, significant features, and the day's sample locations. In addition, water depths, stream velocity, stream color, and temperature are recorded. Lastly, the vegetation around the stream is noted, along with the amount of shade cover; the stream bottom substrate is observed and recorded. Pictures can be taken and included with the sample data. Much of this data is recorded after the dip net hits the water in order to minimize any disturbances to the stream and the macros living in it before the collection.
The preferred collecting tool is the dip net. Designed with a sturdy cloth sleeve and mesh bottom, water can easily pass through and allow macros to collect in the bottom. There are five stream habitat types that RiverWatch samples, using the dip net collecting techniques. In order of preferred use:
Once the samples are collected and placed in buckets, the challenge is to pull the fast-moving macros from their watery homes. This is done using a shallow white pan, forceps, eye droppers, and carbonated water to help slow the critters down. Once captured, the macro makes the ultimate sacrifice, as it is deposited in a vial of pure alcohol for later identification and recording. All the macros taken can be combined into one sample. Once all the macros are pulled from the shallow white pan and put in vials, the gear is packed up and the crew returns to the barn for lunch. After lunch the work of sorting, identifying and counting begins.
Macro invertebrates can be seen with the naked eye, but for identification some of the key differences only become clear under a microscope. For example, mayflies fall into seven categories and key features on the gills, legs, and antennae are more easily seen through a microscope. Damsel fly larva, whether broad-winged or narrow-winged will determine their indicator number. Dragonfly larva are large and don’t need to be identified down to species, only that they are present and the number found. The process of identifying, sorting, counting is continued until the specimens are determined and recorded. The vial containing all the day's collection is labeled and sent to the RiverWatch administrator, who then forwards it on to professionals who double-check identification and the count. Feedback is then provided to the citizen scientist to help improve identification in the future.
Each macro used as an indicator species is assigned a number. The lower the number, the more conservative the species and the less tolerant of pollution and other disturbances. A formula, based on the assigned number of each species, the total count of each species, and the number of organisms found, is used to determine the Macro-Invertebrate Biotic Index (MBI). The lower the MBI number, the higher the stream quality.
Nachusa stream quality is good in Clear Creek and fair in Wade and Johnny’s Creek. It is too early to see a trend in improvement or degradation of water quality. An effort is made to sample the streams close to the same date each year, but an annual variance in weather conditions can account for some difference in the MBI. Only after many years of monitoring are trends likely to be seen. Following the introduction of bison, changes to the stream banks have been observed. In the sample area around Johnny's Creek, the vegetation has been eaten or trampled. Stream banks that were heavily vegetated are now bare. Near Wade Creek bison hair was found on the plants, but no disturbance was noted in the Wade Creek sample area. The changes in streams being made as a result of restoration efforts and the introduction of bison won't be measured in months or even years, but in decades and centuries. Careful observation, good science, sometimes unnerving patience, and prudent management will help restore the portions of these streams that run through Nachusa back to a functioning and evolving ecosystem.
Note: Clear Creek is outside of the bison enclosure.
To volunteer for the RiverWatch program at Nachusa, contact Mary Vieregg. For more information about citizen scientist training, visit the website for Illinois RiverWatch .
The blog today was written by Paul Swanson, a volunteer citizen scientist for Nachusa.
Summer is the busiest time of year on the prairie with seeds ready to harvest and invasive weeds sprouting up. So every May Nachusa hires half a dozen seasonal staff to keep up with the workload. Typically the staff hired are in their twenties and going into careers in ecological restoration/conservation. The crew will spend most of the first half of the summer spraying and spading weeds in the hot sun, and then seeds will be collected throughout the summer and fall as they ripen. In the late summer and fall the crew will plant the seed they collected in a brand new planting that has not seen prairie in recent years. This year's planting is 84 acres! The crew of 2017 has jumped into the summer with great enthusiasm and the prairie is already much improved because of their labors.
Meet this year's seasonal staff:
Kaleb Baker — Crew Leader, on his third season he has been an incredible resource helping with many things, including the new Arc Collector Map service. Kaleb will be with us for a couple more months this summer before he attends NIU this fall to start his Masters’ Degree.
Phil Nagorny — on his second season, he started with Kaleb back in March as our Lead Restoration Technician. He brings a deep skill set and experience operating equipment that we will take advantage of while he is here. He will also be attending NIU this fall to finish his undergraduate degree.
Sebastian Schafer — who came all the way from Germany, has been interning with us since March. He is years ahead of most at his age. He is now heading back home to start his Master’s Degree.
Nathaniel Weickert — from Rockford and recently graduated from NIU. Some of you will recognize him, since he has spent many Saturdays volunteering at Nachusa.
Cody Cassidy — is from Rochelle and recently graduated from University of WI Whitewater. Cody is good with his hands, having grown up working with his dad’s heating and cooling business.
Avery Parmiter — From Connecticut and a recent graduate from Clemson University. She brings an array of recent field experiences to Nachusa.
Sandra Vaughn-Pottorff — Originally from Rockford, she recently returned from Hawaii where she studied environmental sciences. She will be enrolling in NIU to finish her undergraduate degree this upcoming school year.
Leah Kleiman — who we all have seen grow and blossom into a mature young independent woman. She recently completed the second year of her Associate’s Degree at Sauk and is eager to gain more experience working on the crew.
(Bios written by Cody Considine)
Today's blog was brought to you by Leah Kleiman
I have had the opportunity to lead several adult groups on tours of Nachusa and the Tellabs Unit. There is always an abundance of questions and some of the questions asked are the same on each trip. "How many bison are there?", "How big is Nachusa Grasslands", "What is the name of that plant?", "What does 'Nachusa' mean?" On a warm, Sunday evening I accompanied two guests on a romp around the grasslands and the forest. There were no questions, just adventure and play; I even learned a little bit.
A child born near the coast in Washington and a child born in Colorado enjoy the grassland together.
Among the tall oaks and the green herbs broken sticks and sand in the two-track are brushes and easels for young imaginations.
"As a child, one has that magical capacity to move among the many eras of the earth; to see the land as an animal does; to experience the sky from the perspective of a flower or a bee; to feel the earth quiver and breathe beneath us; to know a hundred different smells of mud and listen unselfconsciously to the soughing of the trees." —Valerie Andrews
What I thought could be a lesson on nutrient recycling and fertilization was interrupted so I could be informed that an apatosaurus had accidentally stomped on the egg of a T. Rex.
"We must remain as close to the flowers, the grass, and the butterflies as the child is who is not yet so much taller than they are. We adults, on the other hand, have outgrown them and have to lower ourselves to stoop down to them. It seems to me that the grass hates us when we confess our love for it. Whoever would partake of all good things must understand how to be small at times." —Friedrich Nietzsche
It was a great tour. No scientific names were uttered. No numbers were shared. No ecological concepts were described. Sticks became swords, rocks were thrown, the grass cushioned multiple falls, laughter muted the birds, and a bull bison grazed unconcerned. I encourage you to visit Nachusa and perhaps bring a child instead of a field guide.
"We could have never loved the earth so well if we had had no childhood in it."
Text and photography by Tellabs Steward, Mark Jordan.
We all know Nachusa Grasslands as a place of space. Rolling hills of grasses, seemingly endless skies, and even in the woods or savannas you can see great depths—all tell the spacious story of Nachusa. Looking at things up close tells a very different story. Up close, you see patterns, textures, rhythms that are more abstract. Up close, you see a world more intimate and, conversely, more alien.
A pheasant feather. Though not a bird native to North America, the pheasant is a common sight here. Look at the patterns of lines—lines arrayed as if in motion, branching in multiple directions. The white line down the center, the shaft, like a lightning bolt, gives energy to the feathery lines radiating from it.
The current of Clear Creek molds the sand along the bottom into irregular linear shapes. On the surface, the gold, sinewy lines of sunlight dance across and intersect the darker bottom shapes, forming the warp and woof of a living tapestry.
Focussing now on a feathery image of a different kind, the heads and flowers of Big Bluestem. The photo is framed to capture the more delicate abstract of positive and negative space. The three spikes of the grass, with its dangling yellow flowers form the positive space, while the white, cloudy sky in the background forms the negative.
Even in the most commonplace of subjects, beautiful patterns can be found. This rusted gate at the bison corral may almost seem like an underwater scene, with a school of goldfish swimming in the current. Admittedly, the contrast was pushed a little higher than usual in post-processing this photo to emphasize these patterns, which are really there, but not as visible to the human eye.
A partially burned tree is framed to suggest a kind of rectangular yin/yang symbol. The linear structure, color elements, and burned wood textures all add to the quiet beauty of this rather familiar sight at Nachusa.
To me, ice is endlessly fascinating and I always look for patterns in ice whenever I'm out in winter. The bold abstractions, lines, and movement caused by the ice crystallization has a mesmerizing effect on me. I poetically call this photo: The Heart of Winter. The red "heart" is formed by a fallen oak leaf buried under the ice.
Another undersea view where a goldfish swims over coral and seaweed? No, mosses and lichens exist together in a community on a rock outcrop at Nachusa. This image presents an almost bewildering swirl of color and texture, seemingly in motion, even though every element is securely attached to the underlying rock.
Next time you're visiting Nachusa Grasslands, take a break from bison-watching or cloud gazing and look closely. Look and see. As William Blake said, you can see a world in a grain of sand or heaven in a wildflower.
This blog was written by Charles Larry, volunteer and photographer at Nachusa Grasslands. For more of his images see: charleslarryphotography.zenfolio.com
Milkweeds are a subfamily of the dogbane family (Apocynaceae). Most of us are familiar with the extreme dependency of the Monarch butterflies (Danaus plexippus) on milkweed plants. These native perennials are the only plants that Monarch larvae (caterpillars) will eat. If there were no milkweeds, there would be no Monarchs.
The Monarch butterfly is Illinois’ State Insect. In April and May, Monarchs begin arriving back in Illinois from their winter migration to Mexico. So, this is a good time to take a quick look at a few of the twenty-three species of milkweeds that are known to be native to Illinois. They are a critical part of the habitat needed by Monarchs.
Milkweed is named for its white milky-looking sap, although at least one milkweed species, Butterflyweed (Asclepias tuberosa) has a clear, rather than milky, sap. At one time, various species of milkweeds could be seen growing in most any ditch, vacant lot or fence line; hence the unfortunate “weed” in its name, even though this plant genus has some of the world’s most unique flowers. The botanic name for the milkweed genus is Asclepias. The name was chosen for Asclepius, the Greek god of healing, although some milkweed species are toxic. So much for naming . . .
Let’s look at milkweeds as a group to see what the various Asclepias species have in common. As we proceed, I will begin pointing out some of the characteristics that distinguish one milkweed species from another.
Milkweeds are perennials, generally with leaves in pairs along the stem, or in whorls. The flowers develop in umbels (flower clusters in which all the branches come from a single point).
I’ve chosen to illustrate a couple of milkweed species that have fewer flowers per umbel so that it is easier to really see the typical milkweed umbel structure, as well as the paired leaves on these particular milkweed species.
Once you are aware of the umbel structure, it is much easier to look for and to recognize it, even on the milkweed species that have 25 to 40 or many more flowers per umbel, or that have multiple umbels. See samples in photos below.
Note the slender leaves (about 1 inch wide) of the Swamp Milkweed, as compared to both the Common and the Purple Milkweeds above. The even more slender leaves of the Tall Green Milkweed (slightly over ½ inch wide) are whorled around the stem or alternate, rather than being paired opposites, as is the case with most of our local native milkweed species.
Milkweed flowers are one of the most complex flowers in the plant world, probably second only to orchids. This discussion is limited to the most visible flower parts that are useful in identifying these amazing plants and to see how pollen is transferred.
The flower structure varies somewhat by species, but they all have a vaguely hourglass shape, with each flower having five sepals (that fall back and become hidden by the petals as the bud opens) and five petals that reflex downward when the bud opens (see sketch above).
Most flowers have petals and sepals, but milkweeds are unique in also having a third set of structures just above the petals: five pairs of hoods (where the nectar is) and horns surround the flower column (where the pollen is found in vertical slits there). These hoods and horns are actually modified stamen structures. See the sketches above. The sketch of the Whorled Milkweed shows the flower column that the hoods encircle, the spaces between the hoods and the slits in the flower column. Within the slits, pollinators can encounter the sticky pollen packets through which pollen is delivered to the eggs in the ovary at the base of flower column. In the video below, you can see the orange pollen baskets attached to the bumblebee's back legs; pollen was transferred to these baskets when his legs slipped into those slits in the flower column. Those leg baskets now spread pollen to the subsequent flowers this bee visits.
Fertilized milkweed flowers develop seeds in follicles (pods), with each seed having a coma (cluster of silky hairs) which easily carries the seed on the wind. You are likely familiar with the Common Milkweed pods, which are warty with soft spines, and wider at one end than the other, splitting open when the seeds are ready for the wind to work its magic dispersing them. Showy Milkweed has very similar pods as Common. Other species, such as Purple Milkweed, have pods that are similarly shaped, but downy rather than spiny, or, in the case of Sullivant’s Milkweed, are smoother, with projections only on the upper half. Many milkweed species have slender, smooth pods. All have many seeds packed inside, each with its coma.
As you can see in the previous and following photos, milkweed flower size, color and precise shape all vary by species. These various species also differ in their habitat preferences, from very dry to very wet, from full sun to wooded areas, from sand to heavy clay, from a preference for disturbed soil to an intolerance for it.
The following four species are local native milkweeds that are relatively easy to find if you are interested in seeing them firsthand, and photographing or drawing them (no collecting please). See Recommended Hikes for maps to the search areas I’ve mentioned for each of the species highlighted below.
Many milkweed species are now readily available for purchase at gardening stores or online. If you would like to help to save Monarchs and other pollinators by planting milkweed species in your yard, or at your school, park or business, be sure to purchase species suited to your growing conditions, that are not hybrids,* and that are native to the area where you plan to plant them, ideally within fifty miles. By choosing plants that have co-evolved with pollinators and other insects native to this area, you can be sure you are supporting their life cycles with needed resources.
*In hybrids (and “cultivars”), instead of the simple nectar guides like those of native plants, that can be accessed with a butterfly’s long tongue, “. . . a bloom can be changed enough in scent or shape that butterflies can’t recognize them or access the nectar.” This is just one example of why using native plants is so important. From www.prairienursery.com.
Scientific Name: Asclepias incarnata
General Characteristics & Habitat: typically grows to 3 to 5 feet tall; has deep underground stems; spreads via rhizomes; prefers wet soils (marshes, bogs, ditches). In proper locations, self-seeds prolifically.
Flowers: multiple somewhat flat-topped clusters of flowers at tops of stems and branches; flower petals tend to be pale rose to rose-purple, with whitish hoods.
Bloom time: mid-June to early September
Stem, Leaves, Pods: stems are smooth and branched at the top; leaves are opposite, narrow (about 1 inch wide), oblong or lance-shaped, narrow at the base, and have short stalks. Pods are slender and papery, wrinkled, usually in pairs, terminal on stem.
Finding them to view: along ditches and creeks and other sunny wet areas. At Nachusa Grasslands, areas outside the bison enclosures to look include Meiners Wetlands and Clear Creek Knolls.
See the sketchbook page above for details on habitat, flowers, stems, leaves and pods. How to find them to view? Look in mostly sunny, undisturbed areas, along railroad right-of-ways, typically in drier soils. At Nachusa Grasslands, areas outside the bison enclosures to look include Clear Creek Knolls and Thelma Carpenter Prairie.
If you like a challenge, here are several milkweed species that are much more rare than the above species, that you may be able to locate for viewing and/or decide to purchase to grow yourself. Each is unique, even among milkweed species, in their own way.
The sketchbook page shows details on habitat, flowers, stems, leaves and pods. Where to find the poke milkweed to view? Look in dappled woods or other semi-shaded areas, in rich, moist soil. Don’t give up if you see them one year and not the next — they are known to disappear for years at a time and then reappear in abundance. At Nachusa Grasslands, areas outside the bison enclosures to look include Stone Barn Savanna and Big Jump.
Currently at Nachusa Grasslands, both Sand (above) and Tall Green (below) milkweeds are only known to be within the bison units. Take this as a challenge to find them elsewhere! Sand milkweed is about 2 feet tall, with the flower cluster well above its leaves, in dry, sandy soil where there is sparse vegetation. Tall Green is easy to identify (see below), and seems to like partial shade and soil with good drainage.
Wishing you some happy milkweed exploring!
All photos and video were taken by Betty Higby at Nachusa Grasslands, except the Short Green Milkweed pod, which was taken at Midewin. Text and sketches by Betty Higby, who is a volunteer at Nachusa.
Ephemeral ponds are temporary ponds of springtime, sometimes called vernal pools.
Springtime, melting snow, and spring rains bring water and life to the ephemeral ponds and vernal pools at Nachusa Grasslands. Amphibians and macro invertebrates use these ponds as a nursery for their young. These small bodies of water flourish in the spring and then quietly, without notice, disappear into the heat of the summer. While they exist, they offer special advantages and challenges for the life that inhabits them.
Plants and animals in ephemeral pools must be adapted to wet conditions in spring and dry conditions by early summer. Plants that thrive in vernal ponds are very often the same plants that one would find on the edge of permanent ponds. Permanent ponds overflow their banks in spring and a shoreline of sedges, grasses, and forbs begin to emerge in the cold water. These same types of plants emerge in the cold water of vernal pools. These plants will continue to thrive on the shores of a permanent pond as the water recedes and in vernal pools as the water fades and the pond dries.
Frogs and salamanders seek out ephemeral ponds as safe breeding pools and nurseries for their young. A pond that dries out part of the year, or freezes entirely, prevents fish from establishing. Fish would eat amphibian eggs, small tadpoles, or small sallywogs*; they would also compete for the macro invertebrates that provide a rich source of food for the adult and juvenile amphibians. The trade-off is the young must grow fast enough to leave the pool before it dries in the summer heat.
Nachusa’s ephemeral ponds have the advantage of being surrounded by a rich and diverse grassland. As the ponds dry, the young that managed to mature enough to leave the watery place of their youth, can venture forward into a land of plenty. Appetite-satisfying insects are plentiful. The tall grasses and abundant flowering plants provide camouflage and shelter. This is a sharp contrast to ponds among row crops, where the plants are a monoculture and are frequently sprayed with pesticide. Or, in the suburbs, where lawns are mowed right up to the waters edge, leaving no place to hide; tasty insects are sparse. Many times ephemeral ponds are filled, drained, or dug deeper to create a permanent pond, ruining the qualities that support unique macro-invertebrate and amphibian life. At Nachusa the challenges of survival in the natural world exist for amphibians, but without many of the artificial challenges that the modern world brings.
Nachusa has many of these wonderful ephemeral ponds. They can often be located this time of year by the sounds of calling frogs. Western chorus frogs and spring peepers are the first to begin calling in late March or early April and are later joined by northern leopard frogs and American toads. Readers of the blog are likely familiar with the sound of the western chorus frog, often described as the sound of a fingernail being dragged across the teeth of a plastic comb; or its contemporary the spring peeper whose call begins with peep, peep, peep. The trill of the American toad is long and carries in the night air. The northern leopard frog with its low rumble, is followed by a bit of chuckle. The copes gray treefrog begins calling around early May; its call is a similar trill to the American toad, but instead of a long steady call, the copes trill comes in quick, short bursts often two or three at a time. Listen for calling frogs after the sun sets, when the winds are calm.
One resident of Nachusa is never heard and seldom seen. The silent, but intriguing tiger salamander with its marbled skin, likely visits these ponds as a refuge and breeding site. Presently the pond waters are filled with eggs of frogs and salamanders. Soon these vernal pools will be filled with tadpoles and sallywogs* competing to be the next generation of amphibian life at Nachusa.
As volunteers and staff at Nachusa restore the native landscape, ephemeral-pond-dependent species grow in population and diversity. Drain tiles throughout the preserve have been broken or removed, and low spots have been enhanced to return the natural hydrology to the land and allow spring wet areas to return; this increases the areas for amphibian populations to expand. It has been reported that the call of the plains leopard frog has recently been heard near the Tellabs ponds. If confirmed, another species can be added to the list of animals that call Nachusa home. The ephemeral ponds surrounded by plentiful grasslands preserves the ecological diversity that is the living tapestry of Nachusa Grasslands.
Text and Photos by Paul Swanson
*Sallywogs used to denote salamander larvae vs. frog larvae.
The first day of spring 2017 has arrived! This day marks the equinox, with the sun shining equally on both the northern and southern hemispheres; the result is nearly equal hours of daylight and night. What does this mean for the prairie? Well, longer daylight means those first spring blooms are almost here! With new blades of grass already a couple inches high in the recently burned fields, April will soon bring the year’s first blooms. Let’s take a look at some of Nachusa’s beautiful spring flowers and discover where to find them. All flowers listed below are found in non–bison units and are accessible to everyone.
Before the trees fill their canopies with leaves, several flowers utilize all the sunlight shining to the ground and quickly complete their whole life–cycle; then the entire plant disappears completely, leaving no trace. These short–term blooms are called spring ephemerals.
The bloodroot is an ephemeral found in Nachusa's woodlands and savannas. Its showy white flower creates a great contrast against the forest floor. The plant’s name comes from the red juice that flows when any part of the plant is cut or bruised. Look for bloodroot under the trees in Stone Barn Savanna and Big Jump.
Another ephemeral is Virginia bluebells, and this plant can be quite stunning growing in mass groups. They bring wonderful color to the shady parts of the woodland. Look for Virginia bluebells in moist areas of Stone Barn Savanna.
Has someone been hanging their pantaloons out to dry? Certainly not! These "v-shaped" hanging flowers are found on the aptly named "Dutchman's breeches." Look for the flowers emerging from mounded fern–like foliage. Dutchman's breeches are located in the woodlands of Stone Barn Savanna.
The last featured spring ephemeral is the spring beauty. Spring beauty is a very small plant found in Nachusa’s woodlands and savannas; only 3-6” tall. To identify the flower, look for the dark pink veins found on the petals. This lovely flower can be found in Stone Barn Savanna.
Look for this unusual–looking flower in shady to partial–shady woodland areas. The flower can vary in color from reddish green (like pictured) to whitish green. Hike along the tracks in Stone Barn Savanna to find the jack-in–the–pulpit.
Many geraniums are popular with gardeners as full–sun annuals planted in flower beds or pots. Similar in appearance, the native wild geranium is a hardy perennial flower growing in woodlands. The flowers are very showy and popular among bees and other insects. The flowers can be found in areas of full–sun, part–sun or shade. Look for it in Stone Barn Savanna.
The name of this native flower is easy to remember because its blooms look like little arrows aimed at the ground. Climb along the slopes of Thelma Carpenter Prairie to find the Shooting Star.
Here is a beauty that prefers sandy soils and little competition from other plants. The bird–shaped foliage gives this flower its name. This violet species is very important at Nachusa, for it is a host to the eggs and caterpillars of the state–endangered regal fritillary butterfly. Look for the violet in sandy soils at Stone Barn Savanna and Big Jump.
Looking for wildflowers is like going on a scavenger hunt. It's a lot of fun and you never know what you will find. Remember to "take only pictures and leave only footprints!" Please feel free to share your successes or adventures in the comment section below.
Today’s author is Dee Hudson, a photographer for Nachusa Grasslands. To see more prairie images, visit her website at www.deehudsonphotography.com.
The unseasonably warm weather created a flurry of activity to prepare the fire equipment in anticipation of the weekend's controlled burn. Nachusa burns typically begin in March.
With the staff committed to speaking engagements, much of the prep work fell on long–term and dedicated volunteers, Dave Crites and Mike Carr. This past week, the men worked hard and swiftly to prepare for the possible weekend burns, loading all the various equipment and pumps to the vehicles.
The burn begins, as the crew uses drip torches to ignite the grass.
Water pumpers follow the igniters and extinguish any fire that burns back toward fire breaks.
The crew has the fire well underway.
Crew members dedicated to fire suppression, put out any unwanted fire, such as around this brush pile (it will be burned later, when there is more time to watch over it).
A dust devil was observed during the burn. What causes a dust devil? McKinnon (2014) explains the interesting science:
The controlled burn is typically set in a "ring" by starting at one point and sending two crews in opposite directions, working into the wind. Near the end, the blackened area is wide enough to allow the two crews to meet up in the middle of the wind side. All the "sides" of fire meet up, and with no more fuel, the flames go out!
After the burn is complete, the Project Director leads a debriefing to go over the events of the day. What did we do well? Where can we improve?
Here is a short video detailing some typical events that occur during a controlled burn at Nachusa. For more information, visit Nachusa's webpage about controlled burns.
Today's author is Dee Hudson. Joe Richardson, Charles Larry, Kirk Hallowell, and Bill Kleiman provided the images for this post; John Schmadeke created the video.
McKinnon, Mika, (March 30, 2014).
Science of the Fiery Dust Devil Spawned by a Controlled Burn
The bison reintroduction has been exciting for everyone involved with Nachusa—staff and stewards, volunteers and visitors, and especially scientists. The project provides a unique opportunity measure the impacts of these animals and their actions on the entire restored prairie ecosystem. I’m fortunate to be part of a small army of researchers and students working closely with Nachusa personnel to understand how bison influence plants, animals, and other organisms.
Anyone who has had the opportunity to spend time within the bison units over the past 2 years has undoubtedly seen evidence of these giant herbivores: dung! In addition to grazing on plants and wallowing in dirt, bison play an important role in nutrient cycling by depositing concentrated piles of plant material and nutrients around the prairie. Across the landscape, this may provide hotspots of growth for some plants, adding to the overall diversity at Nachusa.
An inconspicuous group of insects help to carry out this nutrient–cycling process. Dung beetles feed on animal waste, and many species collect dung as a food source for their offspring. Some species famously form it into spheres, and roll these “dung balls” away to bury and deposit eggs. Other species tunnel below the dung patty, building chambers where dung is stored and beetle larvae can develop. And some species are “dwellers” who simply dive in to fresh dung and start to feast, laying eggs along the way. When these eggs hatch, the larvae feed, pupae, and emerge as adults, completing their entire metamorphosis in a single patty before heading off to mate and start the process over again in fresh patty.
Burying small bits of dung in the soil helps make nutrients accessible to plant roots. In the soil, microorganisms like bacteria and fungi convert organic materials into inorganic forms available to plants. This can represent a significant amount of the nutrients. As dung dries, much of the nitrogen can be lost to the air as ammonia volatilizes. This is why dung beetles are important for ranching: every bit of nutrients back in the soil rather than lost to the atmosphere means more fodder for livestock.
So it was a reasonable assumption that the dung beetle community at Nachusa would respond positively to the introduction of several dozen large, dung-producing herbivores to the prairie. I credit Dr. Ken McCravy from WIU for first suggesting that we should investigate these communities. Over the past two years, with support from the Friends of Nachusa Grasslands, I have been working with NIU students to survey the dung beetles to determine which species are present and how their abundances differ between sites with and without bison. We use pitfall traps, baited with fresh bison dung, to collect beetles that are later pinned and identified under a microscope in my lab at NIU.
Our preliminary results are exciting: we have documented at least seven species, including rollers, tunnelers, and dwellers. The two most common species are Onthophagus hecate, a widespread species, and Onthophagus knausi, a uncommon species whose range extends west and south through Kansas, Oklahoma, and Texas. The other species are much less common but include the large, blue-black Geotrupes opacus and the spectacular rainbow scarab, Phanaeus vindex.
As a preliminary result, the presence of bison doesn’t seem to have a big effect on abundance, as some bison-free sites have high numbers of beetles. But this may not be surprising given how mobile these insects are. They can fly and specialize in seeking out their preferred food. Cattle pastures surrounding Nachusa likely provide population sources as well.
Over the next two years, we will be investigating these dung beetle communities in more detail. A Master’s student at NIU will be combining observations of dung decomposition with beetle measurements to understand how different species contribute to dung processing. Ultimately we hope to understand how the management actions that maintain high plant diversity at Nachusa (such as prescribed fire and grazing) affect beetle communities and their ability to process dung.
Keep an eye on fresh dung patties and you may see these small but fascinating insects carrying out some of the invaluable “dirty work” that keeps the prairie ecosystem healthy and biodiverse!
Nick Barber is an assistant professor in the Department of Biological Sciences at Northern Illinois University. To read more about his work, visit the Barber Lab webpage. Thank you Nick, for being our guest blogger this week!
A seed on the wind as it travels alone,
does it feel isolation as it looks for a home?
The breeze carries it aloft and sometimes quite high,
will it land in a spot that is wet or quite dry?
Will the conditions it lands in meet all of its needs,
or would its chances have been better on an easterly breeze?
Of seeds born to the wind there must be many,
so at least a few make it to the land of seed plenty.
Where a cycle of freeze and thaw is step one,
for the seed to sprout it will need good soil and sun.
Bright orange flames of fire flicker on thatch,
to soon leave the prairie a charcoal black patch.
Down came the rain, it fell all around,
it loosened the soil and moistened the ground.
Forbs and grasses of green cover the black,
this seed found a home where the cover does lack.
Grazing the grass fills bison need,
allows warmth and the sun down to this little seed.
From that seed emerged a tiny green shoot,
that soon put down a nice little root.
The bison that graze the grasses down low,
add nutrients and microbes that help the plant grow.
In the place where this little seed did land,
a plant of its species does now stand.
The new root has grown and is now very deep,
so that this plant can survive a long winters sleep.
In the spring, the plant will grow to be tall,
it will flower this summer, and set seed in the fall.
When the fall breeze blows, the seed will take to the air,
hoping to land on good ground that is bare.
Where can one find this wondrous glory?
At a place called Nachusa, that inspired this story!
This poem was written by Paul Swanson, a volunteer at Nachusa Grasslands.
Photos courtesy of Dee Hudson and Charles Larry.