13. How Much of Ohio Was Prairie Before Europeans Took Over? When Ohio became a state in 1803, at least 2% was open prairie. Some more accurate, recent investigations indicate that about 4% was actual prairie. As the textbooks say, most of Ohio was originally forest, along with many larger wooded wetlands, marshes, and bogs. But significant regions of Ohio had large landscape prairies. At the greatest extent just before settlement, Ohio had about 1700 square miles of prairie (1,088,000 acres) of prairie. The major prairie areas are shown on the Prairie Regions of Ohio map below.14. If Ohio Prairies Were Destroyed Before 1900, How Can We Be Sure Where They Were? Good question. Fortunately we know about our destroyed prairies from several accurate sources. The first is the written accounts of early settlers. Because the prairies were so different from the Eastern homeland forest areas from which settlers originated, there are many settler accounts of local Ohio prairies from the early 19th century. These historic writings tell about local prairies, noting the animals encountered there, and the hardships (fires, lack of roads, difficult plowing conditions, other harsh wilderness conditions) that prairie settlers faced.The second strong line of evidence about the size and location of Ohio’s prairies comes from the first official land survey records. Before land could be sold in Ohio, it had to be properly surveyed and the survey results filed in a local courthouse or land office. Because Ohio lands were to be purchased primarily by new settlers from the East who were looking for cheap but productive farmland, the early surveyors kept accurate records of the trees and plants they encountered in their surveys. They were careful to mark the borders of a prairie on their surveys because Easterners originally thought that land that couldn’t grow trees (as on a prairie) had to be infertile and therefore probably wouldn’t make a good farm site. Later, it was discovered that the treeless prairies were extremely fertile.Consequently, the old official land records in all parts of Ohio tell the location and sizes of Ohio’s original prairies.Lastly, remnants of these once-great prairies still survive in ditches, along railroad rights-of-way, in old cemetery corners, and other scattered areas still unshaded by trees. Most Ohio prairie plants were never able to scatter and grow beyond their prairie origins, so today, when we notice a patch of prairie coneflower (Ratibida pinnata) or prairie dock (Silphium terebinthinaceum) growing along a rural lane or an abandoned railroad, we can be pretty sure that these are rare survivors of a prairie that once grew in profusion near the site. By putting dots on a map wherever these prairie plant remnants are seen, the resulting map looks just like the prairie maps made from both settlers’ accounts and like maps from surveyors’ records. Although Ohio’s great prairie landscapes are gone forever, we know for sure where they once were. It’s an exciting story.15. So, Where Were Those Great Ohio Prairies?The records indicate that Ohio’s largest prairies were located in eight major areas (although small prairies existed in all parts of Ohio.) They are shown on the map below. The specific prairie borders here are only generalizations. The shown prairies represent only closely-approximate locations and sizes. Numerous original smaller prairies throughout all regions of the state are not shown here. These weren't Ohio's only prairies–just the largest.• The Oak Openings. In northwest Ohio was the famous Oak Openings prairies and savannas. This region of dry sand ridges and low wetswales was a mixture of dry sand prairies interspersed with flat wet prairies and dry oak savannas. • The Wood County Black Swamp Wet Prairie. Also in northwest Ohio, in Wood County, was a curious large, flat wet prairiesurrounded by the great Black Swamp, a giant elm-ash lake plain swamp forest. The only remnants of this unique prairie now reside in Wood County’s deep ditches that were originally dug to drain the swamp and prairie.• The Castalia - Sandusky Bay Prairie.Further to the east, in Erie and Sandusky Counties, was the Castalia Prairie, a wet fen prairie. Because portions had blocky chunks of tuffa rock, some of the Castalia Prairie was seldom or ineffectively plowed. Consequently, one of Ohio’s finest, intact prairie remnants is the 40-60 acre Castalia Prairie on Northwest Road at the Resthaven Wildlife Area near the village of Castalia. The modern Castalia Prairie remnant retains a number of rare and endangered plants, moths, and other species. The Castalia Prairie, maintained by the Ohio Division of Wildlife at the Resthaven Wildlife Area, is a state natural treasure.• The Firelands Prairie.Nearby, between Bellevue on the southwest, extending northeast to Huron on Lake Erie, was the great Firelands Prairie. The Firelands Prairie was one of the easternmost large prairies in all of North America.• The Sandusky Plains. To the south, in north central Ohio, was a significant region of prairies, known as the Sandusky Plains. This large area straddles the headwaters of the north-flowing Sandusky and south-flowing Scioto and Olentangy Rivers. • The Darby Plains.The sixth great Ohio prairie area was the Darby Plains in the counties west of Columbus. Prairies and savannas stretched across several counties that are, today, an extremely fertile agricultural region. Extensive prairie restorations by Columbus Metroparks are returning several areas to large native prairies. Two state nature preserves, the Bigelow and Smith Cemetery Prairies, and a few railroad rights of way give a glimpse of the botanical beauty of this great prairie area.• Adams County (Lexington Plains) Prairies. In the south, near the Ohio River, in hilly Adams County, there are numerous prairie patches and remnants. The Adams County prairies are noted for their abundance of rare and uncommon prairie species. This interesting region is actually a northern extension of the Kentucky bluegrass ecological region south of the Ohio River.• Mad River Prairie Fens. In southwest Ohio, in the greater Dayton area, were a good number of small valley-bottom fen prairies. Along local rivers and creeks there were a number of larger local prairie landscapes. • Other Ohio Prairies. Other prairies, usually small ones, were scattered across the rest of Ohio. In fact, prairie openings in the Eastern forest extended all the way to the Atlantic Ocean. Ohio is the eastern edge of the large landscape prairies of the Midwest, but small prairie areas were found far to the east. 16. How Can We Know What Plants Were On Original Ohio Prairies? Another good question. We have discovered where Ohio’s prairies were. But do we know what they were, what plant species lived there? Yes, we do, by these means.Neither the early surveyors nor the settlers were botanists. Therefore, the early records merely mention “prairy” or “grasses” or “plains.” The prairie plants were a mystery to those from the forested East. The historical records of Ohio’s early landscapes aren’t much help in determining what prairie grasses and forbs actually grew in the state. But other records do give us a pretty accurate rendering of Ohio’s natural prairie botany.By the end of the 19th century, and well into the 20th, Ohio colleges and universities had botany departments with capable professors and students. These individuals made field collections of local plants and deposited these mounted, dry specimens in college herbaria, repositories of identified, pressed plants. From these many historical records we can determine almost all of the species of plants that once grew in Ohio’s local prairies.For example, in the 1890s a Sandusky High School science teacher, Edwin Lincoln Moseley, frequently took students on all-day field trips to distant parts of Erie County in the northern part of the state. He and his students collected hundreds of plant specimens from forests, marshes, and local prairies, noting the species and locations. E.L. Moseley then compiled this great list of local plants and had it published. There were still many local patches of unplowed prairie, and Moseley’s lists of plants provides an unparalleled picture of the field botany of the great Firelands Prairie once prominent in Erie and Huron Counties. Botanists in other regions of Ohio likewise collected local prairie plant specimens that still survive in historic herbaria.Lastly, rare prairie plant survivors are still being discovered in ditches, along railroads, open woodlot edges, and other isolated spots. Consequently, we have a very accurate listing of what plants lived on Ohio’s prairies. The discovery of these plants, both as inhabitants of the original prairies (from the collected plant records) and also as live remnant populations, has been (and continues to be) a great scientific investigation. Therefore, we now know both where Ohio’s prairies were, and what plants lived on them. 17. What Kinds of Prairie Existed in Ohio? Another good question. A prairie is not just a prairie. There are several distinct types of prairie in North America, and Ohio had examples of most of them.First, the kind of prairie Ohio didn’t have. The great shortgrass prairies of the high plains and regions next to the Rocky Mountains were absent from Ohio. These great grasslands supported the enormous herds of bison (“buffalo”) and the Plains Indians. Rainfall is restricted on these prairies, with just enough (<1 ft, <30 cm) to grow short native grasses. These short grasses are very nutritious and can support large roaming herds of bison. Ohio, however, has too much rainfall for these dry-region grasses. Our prairie grasses were much taller. Ohio didn’t have the kinds of prairies found in Montana, Wyoming, and other Western States. It was too moist for these prairie plants.Ohio’s prairies were tallgrass prairies, prairies that were dominated by two or three species of tall native grasses. The most common of these was the king of the prairie, big bluestem grass. Big bluestem in Ohio grows to 6 - 8 ft or more. Indiangrass is another such grass, followed by switchgrass and prairie cordgrass. So, in general, most of Ohio’s prairies were tallgrass prairies with very tall mature grasses. But prairie ecologists divide the tallgrass prairie into a number of specific kinds, depending on the amount of moisture in the local soil.Two areas may have identical amounts of rainfall, but very different kinds of plants will grow in each. The amount of moisture in soil greatly affects the kinds of plants that will grow on a site. For example, one site may have been flat and wet with heavy clay soil. Nearby could be a rolling site with a sandy soil. Both sites get exactly the same rainfall but will have very different prairie plant communities. Prairies are divided by available soil moisture, in the following categories.Wet (or Hydric) Prairie. A wet prairie experiences lengthy periods of wet or saturated soil. Wet prairies are usually on low or flat sites often with heavy clay soils. Wet prairie plants grow well in these harsh conditions. Wet prairies are often very fertile and always have large amounts of vegetation (biomass). But they tend to have reduced kinds of plants (reduced biodiversity). Wet prairies once covered large areas of Ohio, especially on the flat Lake Plain in the northern counties adjacent to Lake Erie.Mesic Prairie.Mesic (“MEE- zic") prairie grows on soils that are not excessively dry nor excessively moist. Soil moisture is ideally even. Mesic prairie soils are frequently loams, with even amounts of sand, silt, and clay. Mesic prairies have a large number of plant species.Dry (or Xeric) Prairie. Xeric ("ZERR - ic") prairie grows in sand or other dry soils, often on hillsides or other well-drained sites. Because moisture is less available, xeric prairie plants are usually smaller and more widely spaced than those on hydric and mesic sites. But xeric prairies frequently have rare or uncommon plant and animal species. The famous sand prairies of the Oak Openings region west of Toledo are quintessential xeric prairies in Ohio.Then there are two intermediate prairies, sharing some of the qualities and plants of the two adjacent prairie types.Wet-Mesic Prairie.Wet-mesic prairie is intermediate between wet and mesic prairie. A few species of plant prefer wet-mesic prairies.Dry-Mesic Prairie. Dry-mesic prairie is less dry than a xeric prairie, but not as moist as a mesic one. Again, a few species of plants grow particularly well on these prairies.Prairies, then, can be classified by their soil moisture, in this sequence (wet to dry):Wet Prairie – soils very wet for lengthy periods.Wet (or Hydric) Prairie – soils very wet.Wet-Mesic Prairie– soils somewhat wet.Mesic Prairie – soils neither too wet nor too dry.Dry-Mesic Prairie– soils somewhat dry.Dry (or Xeric) Prairie – soils very dry.But this arrangement, based only on soil moisture, fails to identify a few local prairie types that are controlled by other local factors. One important such local prairie is a fen. The word fen comes from Great Britain and Europe where there are landscapes dominated by plants that grow only in wet areas of alkaline or calcareous soils. A number of Ohio wet prairies grow in these soils, the most famous, perhaps, is the Castalia Prairie at the Resthaven Wildlife Area near Castalia, Ohio. Groundwater here rises up through pure limestone and marl (calcium carbonate), making the soil very alkaline (>7pH). A number of very rare prairie species require this wet prairie, fen condition. Many local prairies in southwest Ohio are fen prairies.A few Ohio xeric prairies are so-called “sand barrens,” areas with infertile sand and a reduced number of prairie plant species. Most prairies, even xeric ones, have very fertile soils. Sand barren prairies tend to have infertile soils and support reduced numbers (but very interesting) prairie plant species.Lastly, in steep or hilly parts of Ohio many local prairies are known as “goat prairies.” Goat prairies are apparently called that because only a goat could remain standing in these often rocky, sloped sites. Many of the interesting prairies of Adams County in Ohio’s southern region are goat prairies. Goat prairies may be the only prairies that could survive without frequent fires because they are often on almost vertical, harsh, cliff-side sites where shading trees have a tough time growing to full size. Of course, both sand and goat prairies tend to be dry or dry-mesic prairies.Ohio has a wonderful diversity of prairie types.18. Is a Savanna a Type of Prairie? Well, yes it is, and no it isn’t. True prairies have few or no trees. Unshaded, direct sunlight dominates the prairie landscape.But some prairie areas are curious mixtures of open prairie and scattered forest trees. These are known as prairie savannas. A savanna is generally defined as a prairie area with scattered trees (usually oaks) that allow unshaded sunlight to fall between the widely spaced trees. Beneath each tree, however, the prairie can be quite shaded, creating a varying sequence of shaded to unshaded habitats. Savannas are dominated by scattered oaks, usually of the following species. The classic savanna oak (on wet-mesic, mesic, and dry-mesic sites) is the famous bur oak, Quercus macrocarpa. Also on similar sites can be the great white oak, Quercus alba. Black oaks, Quercus velutina, are common savanna oaks on dry and dry-mesic soils. On wetter sites the swamp white oak, Quercus bicolor, can sometimes be found in a savanna setting.Prairie savannas are important and exceptionally rare environments, some of the rarest in the world. The Oak Openings region west of Toledo has some of the world’s finest prairie savanna habitats, with a large number of rare or endangered plants and animals. Prairie savannas should be specially treasured. Prairie savannas are special places where ecological forces are in centuries-long conflict. As noted at the beginning, a prairie that is not frequently burned soon becomes overgrown and crowded out by shrubs and trees. But in a few areas, usually on lighter, drier soils, fires did not occur with annual frequency. Fires were frequent enough to retard shading by shrubs and brush, but not frequent enough to stop the growth of scattered oak trees. Oaks (and one or two species of hickories) are well-adapted to fire. Most young sapling trees are killed by a prairie fire. And so are oak seedlings if the fires occur almost annually (as they did when Native Americans lived in Ohio). But if prairie fires in dry and dry-mesic areas are slightly less frequent, with occasional fire-free intervals of, perhaps, 10-20 years, then seedling oaks can grow tall enough that the flames of a prairie fire can’t kill all of the limbs. Oak trees, especially those that grow in savannas, have thick, insulating bark, and withstand much hotter fires than other tree species. Oaks are the best-able trees to withstand fires, and therefore in sandy dry prairie areas, where the prairie vegetation isn’t as dense as on wetter sites (has less fuel), oaks can begin to invade the prairie and survive with less frequent fires. After oaks reach 25 ft or more, the heat of a surrounding prairie fire only kills off the lower branches. The tree survives. A savanna is created.If the fires cease altogether, however, new young oaks will start growing densely. In a few short years, the former prairie or open savanna will become a shaded oak forest. This interplay of fire and shade on the prairie savanna makes this rare environment unique and ecologically entrancing. Savannas are special interfaces between the open, sunlit prairie and the fully shaded, tree-canopied forest. Savannas share characteristics of both the forest and the prairie, but in interesting ways unique to this special environment.19. Weren’t Most Ohio Prairie Fires Set Naturally By Lightning, Not Humans? A lot of people think so. They are certain that most natural landscape fires in prehistoric Ohio were touched off by lightning, not by humans. They believe this simply because they don’t think Native Americans had any reason to set wild landscapes on fire, and because they still believe that frequent wildland fire is ultimately destructive. This may descend from the European view of America’s “noble savages,” a perception that Native Americans were never contaminated with the destructive ideas of European life. It is commonly believed that Native Americans always lived in perfect natural harmony with their environment, and in modern western eyes, the frequent setting of wildland fires doesn’t fit with this idealistic (but unsubstantiated) view.Frankly, there is no evidence whatsoever that Native Americans refrained from setting frequent landscape fires in presettlement Ohio. On the contrary, there is overwhelming evidence that natives set fire to virtually all landscapes that would support fire. Only areas that were wet were spared. What is the evidence of frequent, human-set landscape fires? First, we turn again to the earliest written records of Ohio landscapes. Virtually every record of Ohio’s early forests (early 19th century and before) tell of our great forests. But the descriptions of these don’t match with modern forests – and not because modern forests have been logged, either.Early Ohio forest descriptions tell, of course, of the great size of the trees. These great trees could not be harvested without iron tools, unavailable to early Native Americans. Naturally, trees were of great size. But tree size is not an indication of the presence or absence of frequent fire. The absence of fire is indicated by the presence of brush and small trees between the large, mature trees. In virtually every modern Ohio forest (where fires have been absent for decades), the ground layer is covered by low shrubs, brush, vines, and sapling trees. One can often see only a few hundred feet into a modern forest because of the thick, low brush.This modern condition was seldom, if ever, described in early Ohio forest accounts. Early Ohio forests are frequently described as absent of low brush. The forest floors were said to be open, park-like and easily traversed. They this could be arranged only by the frequent burning of the leaves on the forest floor.But couldn’t lightning have set these forest-floor leaf fires? It could, but only rarely. If lightning-caused forest leaf fires were common, then today’s forests would look like early Ohio forests. They don’t because neither humans nor lightning frequently ignite modern Ohio forests. Without fire, forest-floor brush continues to choke the modern forest. Native Americans abhorred this brush because it made walking difficult. Like it or not, Native Americans frequently burned Ohio’s landscapes, even the forested ones.But the greatest fires, of course, were the prairie fires. Annual fall or spring leaf fires had low flames that moved slowly across the forest floor, killing brush and small trees, leaving the large trees unharmed. But prairie fires were very hot, quick, and fast-moving. What is the evidence that humans set these areas on fire?The best evidence is that there were large prairie landscapes in Ohio. The undeniable truth is that any unburned (or un-mowed) Ohio prairie will in a decade or so become brush-shaded and lost. Fires are essential factors in the maintenance of prairies in high-moisture areas such as Ohio. If there was a natural prairie, there was frequent fire. Otherwise, the prairie became shaded and lost to brush and forest.But still, why didn’t natural lightning keep Ohio’s prairies sufficiently burned? That’s the crucial question to ask anyone who contends that Ohio prairie fires were a result of lightning, not humans. The question is, “What is the evidence that natural lightning was the major cause of Ohio prairie fires?” No such evidence has ever been presented. Still, many conveniently attribute Ohio prairie fires to lightning, mostly because they have no reason to believe that Native Americans would have done this. But, they did.Again, what is the evidence? It is this. All Ohio fire departments are required to report to the state fire marshal the cause, size, location, type, and other information on every fire responded to in Ohio. Consequently, an examination of the state database on reported wildland fires will reveal their locations and dates. This has been done (the analyzed data are too lengthy to include here), and the modern lightning-set wildland fire data show that today there are never enough lightning-caused wildfires to maintain Ohio’s prairies.For example, most of Ohio’s lightning occurs during the “green” months, in late spring, summer, and early fall, when prairies are green and actively growing. Anyone who has tried to burn a prairie during this period knows that even setting such a fire is difficult, and getting it to spread further into the green prairie is slow and uncertain. Green grass doesn’t burn well, even if it’s 6 ft tall. Real prairie fires, ones that kill brush and seedling trees, occur either in late fall, after the vegetation is somewhat dry, or in March or April when prairie vegetation has almost completely dried and is very flammable.The fire marshal lightning fire data simply show that very little ground-touching lightning occurs in Ohio when prairies could be easily set afire. There is no reason to believe that lightning occurs less frequently today than it did several hundred years ago.Lastly, unlike in the Rocky Mountains where “dry” lightning is well known, Ohio lightning is commonly accompanied by drenching rain. Even if Ohio prairies were occasionally touched by fire from the sky, the concomitant rain would have extinguished any fire spread.Then, there is a very significant, but little-recognized final reason Native Americans set prairies (and forest floors) on fire each year — hygiene. Unburned natural areas harbor dense populations of ticks and chiggers, which can both cause discomfort and transmit diseases. Native Americans understood that burned areas had reduced populations of human ectoparasites; life in those areas was more pleasant, more healthful. In summary, the only way prairies could have existed for 5000 years or so in Ohio was for them to have been frequently set afire by human beings. Without those fires, Ohio’s great forests would have soon over-shaded the sun-dependant prairies. But human-set fires retarded forest expansion into the prairie, and also provided deer-attracting areas that could be easily “hunted” by the game-confining and game-herding fires themselves. Dry lightning, in dry environments, when prairies can be burned in late fall and early spring, simply doesn’t occur often enough to maintain large prairie landscapes in the Buckeye State. Ohio prairies were therefore anthropogenic, human-caused. Ohio prairies are a valuable, direct natural legacy of Ohio's great Native Americans.Native Americans didn't just live on Ohio's prairies, they created and maintained them.
Frequently Asked Questions About Ohio Prairies P. 2