Tallgrass Prairie (Interior)-IC

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Fire on Tallgrass Prairie (A Flash Fire of a Lesson)

517. All real rangemen love to burn- Fire was a natural component of grassland ecosystems long before man appeared on Earth. Fires which were ignited by natural sources, especially lightening, occurred for millinia before evolution of thinking man (Homo sapiens). Fires ignited by lightening are as much an atmospheric phenomenon and component of climate that determines structure, function, and productivity of grasslands as are precipitation patterns (including drought), temperature regimes, wind, etc. Prehistoric men took their lessons from Nature and fired their ranges in order to produce more feed for game, facilitate hunting and travel, encourage growth of medicinal and pot herbs, and even as a tool of war against enemy tribes. In the Americas white men adopted this practice of the Indians but were careless and excessive in the practice. Thus the first professionally trained range and forest practitioners over-reacted against the otherwise wise use of this essential environmental (largely climatic) component as a tool in Range Management and Forestry. Understandingly this lead to the unwise policy of fire suppression in the name of conservation. Campaigns initiated to stem overburning “backfired” and grasslands were invaded by trees and shrubs, especially when combined with overgrazing. We are slowly relearning the lessons taught by our aboriginal brothers and using prescribed burning as a management practice. Ranchmen in the marvelous “cow country” of the Flint Hills-Osage and Cherokee Prairies Region of Kansas and Oklahoma never forgot the teachings of the Indians. Spring burns are a routine practice among progressive prairiemen. A prescribed spring burn on an excellent big bulestem-upland switchgrass range in the Osage Questas of the Central Lowland Prairie Province. Greenwood County, Kansas. April. Excellent general sources for role of fire on vegetation and in Range Management and Forestry include such standards as Kozlowski and Ahlgren (1974), Wright and Bailey (1982), Chandler et al. (1983), Biswell (1989), Whelan (1995), Bond and van Wilgen (1996), and DeBano et al. (1998). The definitive work on fire and grasslands is Daubenmire (1968). Fire in the central North American grasslands was discussed in the symposium procedings edited by Collins and Wallace (1990). The definitive summary of fire as an ecological factor in range ecology remains chapter 9 in Humphrey (1962; ps. 148-189) while the classic for use of fire by man in agricultural practice is Sauer, (1952; ps. 10-18) and for general grassland management, Sauer (1950). Man’s use of fire in an historic context was covered comprehensively in the series by Pyne (1982, 1984, 1991)  "I know of no basis for a climatic grassland climax but only of a fire grass ‘climax’ for soils permitting deep rooting." (Sauer, 1950, p.  ).

518. Growth of bottomland switchgrass 14 days post burn- Erath County, Texas, March.

519. Growth of bottomland switchgrass 31 days post burn- Erath County, Texas, April.

520. "The only thing that makes me happier than fire is water"- Dense stand of big bluestem on a Flint Hills range about five months following a spring (April) prescribed burn. On the left (to left of conspicuous Baldwin ironweed in center) was an experimental plot that had been treated by repeated spring burns every third year for a number of yeards prior to the current growing season prescribed fire. Many of the tillers of big bluestem had developed into sexually reproductive (flowering) shoots in response to this current growing season burn that was part of the every-third-year burning fire regime. Current and regular periodic spring fires served to elicit this morphological-physiological response. Increased incidence of flowering along with greater density of shoots and height of individual shoots following spring fire is a typical response of big bluestem on tallgrass prairie (Knapp et al. 1998, ps. 203-205). On the right (right of ironweed) another plot had been fired in the same April burn (five months prior to photograph), but this portion of the big bluestem-dominated tallgrass prairie had not been subjected to fire for the last consecutive 15 years (growing seasons). By contrast, big bluestem on this experimental plot did not respond (at least not as greatly) to the spring prescribed fire (ie. there was no increase in flowering, shoot density, or shoot height). This is also a typical result to grassland fire for this climax vegetation. It is apparently the entire fire regime (pattern, including chronology, of burning as well as season, intensity, kind of fire, etc.) and not just conditions of the current fire that is responsible for prairie plant responses to burning. Konza Prairie, Riley County, Kansas. Early August.

521. "Fire? It's about time!" (Or "You're years late")- Stand of big bluestem on the same Flint Hills range and burned by the same April fire as some of the prairie vegetation presented in the immediately preceding photograph (that to left of ironweed) except that this experimental area had not been burnt for 15 consecutived years prior to the current growing season prescribed fire (five months previous). Big bluestem did not respond to the same degree with regard to shoot flowering, density, and height as did big bluestem in adjoining plots that had received spring (April) burns every three years. However, shoot response, especially flowering, was greater than that under annual burning (the every year for eight consecutive years treatment). Again, it is the complete history or fire regime that is important in determinig response of grassland plants to any given fire. Konza Prairie, Riley County, Kansas. Early August.

522. "Another fire? So what else is new?"- Upland big bluestem-dominated tallgrass prairie range that had received prescription fires for the last eight consecutive springs. This was another experimental plot adjacent to the plots ahown and discussed in the two immediately preceding slides. On this range plot there was no increase in sexual reproduction by big bluestem due to fire (there was very little flowering at all). Furthermore, biomass production was about the same between this annually burned tallgrass prairie and that of companion plots that were burnt only one year every 15 years. The main difference between such extreme fire treatments was in flowering rate (proportion of sexually reproductive shoots) of big bluestem and general appearance of the vegetation (less standing and down detritus from previous years on the plot having yearly prescribed fire). Synopsis of burning "shedule": 1) burn every year (as for eight years straight) there is no increase in shoot flowering, density, or height; 2) burn irregularily (as only one year in 15) results in some increase of flowering (development of asexual shoots into sexual shoots), but not as much as at closer interval (say, every third spring) while herbage yield is similar to that under annual burning; 3) burn at regular multi-year spaced intervals (at, in this trial, every third year) there was a big increase in shoot density, height, and flowering rate. Konza Prairie, Riley County, Kansas. Early August.

523. Blackjack oaks top-killed by a hot heading fire on a big bluestem-dominated loamy prairie range site. Blackjacks are resprouting (weakly) from the up7er roots and stumps but continued prescribed burning at intervals of three to five years will reduce oak cover and maintain the fire-type tallgrass prairie in the Cross Timbers Region. Five weeks post burn. Tallgrass Prairie Preserve of The Nature Conservancy (but it was the stewardship of the previous owner, the famed Chapman-Barnard Ranch, whose management  preserved the Excellent range condition of this pristine grassland). Osage County, Oklahoma, May. FRES No. 39 (Prairie Grassland Ecosystem). K-66 (Bluestem Prairie). SRM 601 (Bluestem Prairie) and/or 710 (Bluestem Prairie). Cold Temperate Grassland 142, Plains Grassland 142.1, Bluestem "Tall Grass" Series, 142.11 of Brown (1998, p. 40). Transition of Flint Hills Ecoregion 28a and Northern Cross Timbers Ecoregion 29a (Woods et al., 2005).

524. Hot improvement- A cow-calf range on tallgrass prairie (big bluestem, switchgrass, and Indiangrass dominants with tall dropseed and Canaada wildrye as associates) that had been prescribed burnt about two and a hald to three months previously. This range had not been burned for several years and had a serious invasion of roughleaf dogwood, bois d'arc or Osage orange, and honey locust. On this upland range site the prescribed burn had done an outstanding job of topkilling almost all woody plants. This tallgrass prairie was in an area that was a transition between the Flint Hills and Chautauqua Hills sections of the Central Lowlands physiographic province. The natural (climax) vegetation of the Chautauqua Hills is Northern Cross Timbers so incursion and invasion of woody species is in the natural order of things-- as is prairie fire. And Mother Nature always welcomes the helping hand of man in regards range improvement by hot spring fires. House Hereford Ranch, Crowley County, Kansas. Late June (early vernal aspect). FRES No. 39 (Prairie Grassland Ecosystem). K-66 (Bluestem Prairie). SRM 601 (Bluestem Prairie) and/or 710 (Bluestem Prairie). Cold Temperate Grassland 142, Plains Grassland 142.1, Bluestem "Tall Grass" Series, 142.11 of Brown (1998, p. 40). Flint Hills Ecoregion, 28 (Chapman et al., 2001).

525. Hot enough for ya?- Four Horsemen tallgrass prairie (with tall dropseed and Canada wildrye as associate species) range that had been seriously invaded by roughleaf dogwood, bois d'arc or Osage orange, and honey locust about about two and a half to three months following a prescribed burn. Almost all woody plants had been topkilled except for a few shoots of roughleaf dogwood and one crown of bois d'arc that had somehow (and most unfortunately) been spared. These woody species will almost assuredly sprout back, but fuel for prescription burns is a renewable resource. Bois d'arc is especially sensitive to fire. If trees of this species are not in the middle of a thicket where grass herbage is minimal (as was the situation with regards the live crown of Osage orange here) they will be quickly topkilled by a typical spring burn on tallgrass prairie. This is the case even for especially large trees. These dead trunks can then be harvested for use as the most durable of all wooden fence posts. House Hereford Ranch, Crowley County, Kansas. Late June (early vernal aspect). FRES No. 39 (Prairie Grassland Ecosystem). K-66 (Bluestem Prairie). SRM 601 (Bluestem Prairie) and/or 710 (Bluestem Prairie). Cold Temperate Grassland 142, Plains Grassland 142.1, Bluestem "Tall Grass" Series, 142.11 of Brown (1998, p. 40). Flint Hills Ecoregion, 28 (Chapman et al., 2001).

526. We like it hot and moist- Example of the range vegetation of the tallgrass prairie that had been burned about two and a half to three months previously on an upland site. This was the same cow-calf range shown immediately above. Local sward of big bluestem, switchgrass, tall dropseed, and Canada wildrye. Indiangrass was present, but not abundant in the "photosample" presented here. There was some of the naturalized Eurasian Japanese brome or Japanese chess. Forbs were absent House Hereford Ranch, Crowley County, Kansas. Late June (early vernal aspect). FRES No. 39 (Prairie Grassland Ecosystem). K-66 (Bluestem Prairie). SRM 601 (Bluestem Prairie) and/or 710 (Bluestem Prairie). Cold Temperate Grassland 142, Plains Grassland 142.1, Bluestem "Tall Grass" Series, 142.11 of Brown (1998, p. 40). Flint Hills Ecoregion, 28 (Chapman et al., 2001).

Natural Revegetation of Tallgrass Prairie

Shown in the following short section were two examples of ongoing natural restoration of tallgrass prairie, recovery of the native prairie plant community through secondary plant succession. One of these recovering prairie ranges was on a bottomland range site while the other was on an upland range site. Grassland vegetation on bottomland had progressed along its sere to climax whereas the upland prairie plant community was roughly in mid-sere with climax grass species just becoming established. Both of these short photographic case histories were on old fields or "go-back land" that had been farmed (row crops and small grains on both fields) for several decades (both for at least a half century) and then retired from farming. The old fields were then abandoned for a period of about 40 years on bottomland and 20-25 years on the upland prairie site. (Obviously there were two different potential climaxes or terminal range plant communities.) No attempts at artificial revegetation such as reseeding had been made on either of the old fields. The bottomland had been mowed for hay once annually since shortly after abandoment. (No comment necessary to describe forage quality--or lack thereof--in early years of vegetation recovery.) The old field on the upland site was mowed annually for hay only a few times afterwhich it was completed "idled" with grazing limited to native animals. The author grew up with and watched land use and recovery of range vegetation on both of these old fields over the course of his lifetime. No systematic records were kept because the author was not present at all times and therefore could not keep accurate or complete notes on management. The following photographs with empherical and incomplete observations were examples of what F.E. Clements called "dynamic vegetation", plant community development by the set of processes known as plant succession (secondary succession in these two instances). These lessons in old field succession were Vegetation Science applied to Range Management as taught in Nature's own lecture hall. Some fellow rangemen and students of vegetation have not so been so fortunte as to have seen such successional sagas unfold. Ya'll will have to be satisfied with this personal and partial narrative, at least until your're better paid.

527. Its reign regained- An old field that through secondary plant succession returned to climax vegetation of mesic tallgrass prairie in the western Ozark (Springfield) Plateau roughly 40 years following cessation of farming. The dominant--far and away--on this Bottomland range site was eastern gamagrass with secondary, though abundant, species including blackeyed susan (Rudbeckia hirta), rosinweed (Silphium integrifolium), purpletop, common wild four o'clock (Mirabilis nyctaginea), and a few seedlings of black walnut (Juglans nigra). When in high school the author helped farm this ground seated on a John Deere Model A. He hauled pea and millet hay (a catch crop planted in a summer drought) off of this little field 45 years before he took these photographs. This land was farmed for a period of about five to seven years after that at which time it was retired from farming by the old couple who owned it. . The field had been mowed once each summer after farming ceased with the first yers hay crop consisting of crabgrass and annual weeds (cows had nothing better to do than pick out grass according to the elderly owners) Annual mowing in late summer has continued ever since tillage ceased. There were no management inputs except for hay harvest. This author first saw eastern gamagrass on the old field approximately 30 years following abandonment. The recovered grassland vegetation shown here was as it appeared about 40 years since the last pass with the plow. A most remarkable story of natural revegetation through secondary succession. Where did the caryopses of this granddad, decreaser grass come from? This little field was on the outer (upper) floodplain of a typical Ozark creek. A climax sugar maple (Acer saccharum)-basswood (Tilia americana)-white ash (Fraxinus americana)-pignut hickory (Carya cordiformis) forest that developed on the north slope of bluffs along the creek was only 70-80 yards from the range plant community shown here. There was no eastern gamagrass in that north slope mesic forest. Likewise, the author was unaware aof any plants of eastern gamagrass upstream from this field. A few other plants of eastern gamagrass were growing in the fencerow across a county "dirt road" from the recovered old field-vegetation presented above. What was their source" Was it the same as that of the ones on this abandoned field or did those across the road come from grain disseminated from this old field stand? So where did the initial Tripsacum dactyloides germinules of recovery emanate from? What where these plant propagules?. The first question above implied that grain was the source of this regenerated stand of eastern gamagrass. The more recently established (the younger) individual clumps of eastern gamagrass appeared to have originated from the initial plants established earlier in ssuccession, and probably by grain disseminated short distances. But what (and where from) were the first disseminules that led to establishment of eastern gamagrass in the revegetation process? Caryopses? Perhaps grains in the soil seed bank that had laid dormant decades. Or could they have been rhizomes, those big, scaly rootstocks of this grandpaw grass species? If initial reestablishment was by asexual reproduction (as from rhizomes) whinther these propagules? Obviously God alone knows. It was a miraculous recovery of a bottomland tallgrass prairie. That much is known by those with their imperfect knowledge. Or perhaps not miraculous at all (except in the sense that a sunrise or birth of a new calf are miracles), but rather the inevitable return of a "super organism" inexorably developing along its sere with the particulars of plant migration yet to be discovered by those who follow F.E. Clements. Trees in the background were those of a bottomland forest adjoining a typical Ozark creek. Many of them were sycamore (Platanus occidentalis), honey locust (Gleditsia triacanthos), white ash, and pignut or bittrnut hickory immediately upstream from the sugar maple-basswood-white ash community that developed on bluffs above the creek. There was certainly no plants of eastern gamagrass or rosinweed in these forest communities. The thin, buff-colored strip of vegetation between creek bottom forest and eastern gamagrass-dominated grassland was naturalized tall fescue (Festuca arundinacea). This agronomic species has naturalized over much of the Ozark Region and is frequently a noxious species especially on tallgrass hay meadows and pastures. Tall fescue stood no chance against eastern gamagrass and, in fact, the latter was slowly encroaching on the stand of tall fescue. Sic 'em grandpaw! Ottawa County, Oklahoma; greater floodplain of Modoc Creek. July (estival aspect); peak bloom in the most common composite species and grain-ripe to grain-shatter in eastern gamagrass.

528. Throne reclaimed- Stand of eastern gamagrass with rosinweed as the local assocaite species on an old farm field that revegetated through secondary plant succession to a climax, bottomland tallgrass prairie in the Ozark Plateau. This was another view of the same old field and natural restoration of potential natural range vegetation introduced in the preceding two photographs and described thereunder. The creek bottom forest and narrow strip of tall fescue behind the eastern gamagrass and rosinweed was also described immediately above. It bore repeating that eastern gamagrass was slowly invading the established sward of the naaturalized, often weedy, tall fescue. (That vegetational development also makes frequent visits to this recovered tallgrass prairie range well worth the short excursions.) Ottawa County, Oklahoma; greater floodplain of Modoc Creek. July (estival aspect); peak bloom in rosinweed and grain-ripe to grain-shatter in eastern gamagrass.

529. Regaining its ground- The climax regime of tallgrasses (here represented by big bluestem and upland switchgrass) was slowly--perhaps inexorably--returning to an old field 20-25 years post abandonment following at least 60 years of farming. In fact, this land could have been farmed for as long as 70 or even 80 years, but there was living locals who could remember back to that time. This old field had produced various crops including wheat (Triticum aestivum), dent corn ( Zea mays var. indentata), grain sorghum (Sorghum vulgare= S. bicolor), and soybeans (Glycine max) for at least the better part of six decades. Even the exact time (year) of the last field crops was apparently forgotten by current owners, but the author who was raised in this locality can trace the point of retirement from cropping from roughly 20 to something less than 30 years prior to time he took these photographs. No attempts at artificial revegetation were made. Seral vegetation on this "go-back land" was mowed for hay one time in each of a few summers (exact number of hay harvests was unknown to the author), but this was soon discontinued. No mowing had taken place on this old field for at five or six years prior to the year in which these photographs were taken This land had passed through the textbook sequence of old field succession from an initial pioneer sere of crabgrass, horseweed, giant ragweed, old field (annual) threeawn, redroot pigweed, and some cocklebur through to the seral community dominated by biennial forbs and weedy or ruderal perennial grasses, especially the native broomsedge bluestem and the naturalized Johnsongrass. The seral plant community shown here and in the succeeding photograph was the latter phase of the weedy, perennial (with lots of anuals and biennials still present) stage that was progresssing into the next (another mixed) stage of weedy perennials grasses plus weedy forbs and with initial establishment (Clementsian migration) of native climax (decreaser) tallgrass species. Big bluestem and switchgrass of the upland form as the first of the Four Horsemen tallgrasses had achieved a successional "beach head" on this "go-back land". Thickening of these individual clumped plants by increasing number of shoots (asexual reproduction) was part of the process Clements called aggregation (Weaver and Clements, 1038, ps. 4, 145-147). This was the second example presented in this section showing natural recovery of tallgrass prairie in the western Ozark Plateau by secondary plant succession. The same question that was asked for the first example presented and described above was reasked here, "Where did the plant propagules of these climax grass species come from?" How did the initial disseminules get here or, if present from the initial virgin sod that was plowed 60 to 80 years previously, how did they persist under decades of farming? What were the germinules? Tiny, fluffy spikelets? Fragments of rhizomes or rootcrowns?. What were the agents of dispersal (wind, birds, rodents, even farm implements perhaps)? Numerous plants of big bluestem were growing within approximately one-fifth mile from these plants, but the author was unaware of any switchgrass within a five mile radius. Imponderables. Broomsedge bluestem was the dominant plant in this mid-sere vegetation. The associate species varied locally and seasonally. For example, in this late spring society the naturalized Eurasian biennial umbel, wild carrot or Queen Anne's lace (Daucus carota), was the major forb and a local associate. Other major species included Johnsongrass (Sorghum halepense), a naturalized perennial grass that was also a local associate, hairy crabgrass (Digitaria sanguinalis), Japanese chess (Bromus japonicus), yellow hop clover (Trifolium agrarium), and tall fescue. Clearly, exotic invaders dominated range vegetation on this old field; it was also obvious that the native decreaser tallgrasses had invaded so that aggregation was underway and migration ongoing. Ottawa County, Oklahoma. Mid-June (vernal aspect); various phenological stages depending on plant species.

530. Winter yet a new beginning on an old field- Scene of the recovering upland tallgrass prairie just shown in the winter following the above summer scenes. Most of the herbage was broomsedge bluestem, but three plants of switchgrass (upland form) were present (foreground to near background). There were even more plants of big bluestem, but the readily degradable shoots of this decreaser had already decomposed to the point of falling to the land surface. Ottawa County, Oklahoma. January (hibernal aspect); depth of winter dormancy.

531. The rocks of salvation- A local colony of big bluestem (foreground of first photograph and right fore-to mid-ground of second photograph) growing out a pile of rocks that had been removed from the innediately adjoining tallgrass prairie hay meadow. This meadow was in the western margin of the Springfield Plateau section of the Ozark Plateau physiographic province as part of the vegetation in a more southern part of the Prairie Peninsula, the region-wide mosaic of tallgrass prairie and oak-hickory forests. The potential natural (climax) vegetation of this grassland was dominance by big bluestem over most of the area with dominance by switchgrass in lower spots and on mima mounds and by Indiangrass on local habitats of thinner, drier soil. Other important grasses were purpletop and Virginia wildrye in more more moist microsites. Prairie dropseed was rare, but diagonostically present. There were numerous species of forbs including ashy sunflower (Helianthus mollis), the most abundant forb, prairie blazing star or prairie gayfeather (Liatris pycnostachya), rattlesnake master (Eryngium yucccifolium), and whole-leaf rosinweed (Silphium integrifolium). Unfortunately this virgin grassland was not in pristine condition. For at least 45 years it had been mowed for prairie hay in late August to mid-September (to get maximum hay tonage) which at this latitude does not leave enough time before frost so that the potential (former) dominant, panicoid, tallgrass species can replinish reserves in roots and rootcrowns to survive through dormancy. Consequently much of this lovely meadow had become nothing but a population of tall or littlehead nut-sedge (Scleria oligantha). The author worked in this meadow in his youth and followed the sad gradual decline in hay production for over four decades. Rocks are the bane of hay makers because even small stones can result in breakage of sections or even knives of mowing machines, especially sickle-bar mowers traditionally used on prairie hay meadows. On this hay meadow rocks of various sizes were picked up over the years and piled in the fenceline at the edge of the meadow. In this protected spot (a mowing machine exclosure) big bluestem had returned to its former dominance to hold vigil over the degraded virgin sod. In this prairie hay meadow the most critical of the Four Cardinal Principles of Range Management was Proper season of Use. Late-mowing of warm-season tallgrasses is one of the most destructive forms of mismanagement. One good feature of this improper haying was that the hay had been mowed high (about six inches or more) so that some photosynthetic tissue had been spared. Otherwise, the tallgrass vegetation would be an even greater disaster than it was. Note the much greater density of forbs like prairie gayfeather in the vegetation that received the late-season mowing. By the way, greed and ignorance are the two words that most explain such short-sighted late harvest by hoping (in vain) for maximum tonage. The realized results of such poor stewardship are lower yields each consecutive year along with minimal forage quality/nutritive value due to harvest at plant maturity. Ottawa County, Oklahoma. July, nearing peak standing crop. FRES No.39 (Prairie Grassland Ecosystem). K-66 (Bluestem Prairie). K-73 (Mosaic of K-66 [Bluestem Prairie] and K-91 [Oak-Hickory Forest]. SRM 710 (Bluestem Prairie). Plains Grassland 142.1, Bluestem "Tall-Grass" Series, 142.11 of Brown et al. (1998, p. 40). Ozark Highlands- Springfield Plateau Ecoregion, 39a (Woods et al. (2005).

532. It can come back- Recovery of a degraded tallgrass prairie hay meadow that for several decades had been mowed in late summer. This meadow was adjacent to the one described in the two immediately preceding photographs. Big bluestem was the overall potential dominant (Indiangrass and switchgrass the associates to local co-dominants) of this prairie vegetation. After years of hay harvest too late in the warm-growing season the three dominant tallgrass species (the decreasers; the climax dominants) had been all but extirpated from this meadow which had become mostly a patch of prairie gayfeather. Cutting late in the growing season of herbaceous species may not allow adequate time for replinishment and storage of reserve food in stem bases, root crowns, and roots to permit survival during dormancy. Consequently with late haying some plants of later-maturing species may die out so that over a period of years those species are lost from the plant community only to be replaced by species that have already completed their annual cycle prior to time of mowing. This is retrogression just the same as with overgrazing. In this case it is a form of overmowing or, more, precisely, improper timing of mowing (ie. more a case of imporper season of harvest than of imporper degree of harvest). Net result is the same: a degraded hay meadow. Fortunately ownership of this hay meadow changed. The new landowner hayed this meadow in early summer instead of late summer or early autumn (at least six to eight weeks earlier than the previous landowner). After about six years or earlier mowing the decreaser tallgrasses, especially big bluestem, had made marvelous recovery and the forage resource was in an advanced state of restoration. The result of prairie recovery was shown in these two "photoplots". Note that some plants of the weedier forbs such as prairie gayfeather and Baldwin ironweed were still obvious in the recovering plant community, but they were much less abundant than under late hay harvest. At time of photographs (middle of July) big bluestem, the almost exclusive tallgrass species, had not commenced elongation of its tillers but leaves were pretty much at maximum size and development. This is the latest in the warm-growing season and the most advanced stage of phenological development at which species like big bluestem should be harvested for hay. In fact, mid-July at this latitude (the Oklahoma-Kansas stateline) was already too late in the growing season for proper hay harvest of long-shoot species (those that elongate tillers early in the annual plant growth cycle) such as Indiangrass and switchgrass, the climax associate tallgrass species on this meadow. This was undoubtedly a factor--in addition to big bluestem being slightly better adapted to this range site--why big bluestem showed greater recovery than the associate tallgrasses and dominated the meadow vegetation. So where did all of the big bluestem come from? How did it get there so fast (six years from a population of almost nothing to dominance of the prairie vegetation)? Answer: it was probably there all along, but plants were kept at such a suppressed, stunted, depapurate, barely alive state that earlier-maturing (mostly weedy) plant species over-shadowed, outgrew, and generally overwhelmed the decreaser tallgrasses like big bluestem. When earlier haying resulted in mowing of the earlier-maturing weedy forbs and grasslike plants, like prairie gayfeather and tall nut-sedge (Scleria oligantha), when they were more vulnerable, and at phenological stages of the natural (climax) dominants when these species were more tolerant of defoliation, the competitive advantage shifted back to the decreasers and they regained dominance of the prairie plant community. The decreaser tallgrasses had been so weakened and stunted that only special forms of sampling and range analysis would have shown their existence on the meadow. With almost any standard method of analysis taller, larger plants on the prairie would be recorded and found to have greater relative proportions (density, cover, frequency, biomass) than smaller, "runt" or "scrub" plants of species that under natural conditions would have dwarfed plants of smaller-growing (and low-seral stage) species. For example, with point sampling (as with point frame or step-point methods) based on "first hit" (the first plant species contacted with the dimensionless tip of a pin) and with subsequent species composition determined from recorded initial contact, the overtopped, depauperate tallgrasses would not have have been recorded. Recording basal "hits" (contact of pin point with plant tissue on the soil surface) would not have given results that were much different because, again, the plant bases of decreasers would have been smaller while those of invaders would have been larger. This would be more so for grasses and grasslike plants (eg. tall nut-sedge) than forbs, but here, too, remaining robust plants of graminoids were be increasers or invaders like broomsedge bluestem and tall nut-sedge. The thing to remember by landowners, rangemen, and other students of natural vegetation is that vegetation can return through plant succession, the depleted forage crop can recover and be restored--to a point anyway--by proper management. A mowing machine can be just as selective a grazer as an animal because the animal that determines selectivity through timing (season), frequency, intensity, etc. of defoliation is the human manager. Understanding this fact is a cornerstone of husbandry. Given a chance it can come back. Ottawa County, Oklahoma. Mid-July; nearing peak standing crop (big bluestem, a short shoot species, had not yet started to elongate tillers). FRES No.39 (Prairie Grassland Ecosystem). K-66 (Bluestem Prairie). K-73 (Mosaic of K-66 [Bluestem Prairie] and K-91 [Oak-Hickory Forest]. SRM 710 (Bluestem Prairie). Plains Grassland 142.1, Bluestem "Tall-Grass" Series, 142.11 of Brown et al. (1998, p. 40). Ozark Highlands- Springfield Plateau Ecoregion, 39a (Woods et al. (2005).

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