Native Americans, Ecosystem Development, and Historical Range of
Transcription
Native Americans, Ecosystem Development, and Historical Range of
Chapter 6 NATIVE A MERICANS, ECOSYSTEM DEVELOPMENT, AND HISTORICAL RANGE OF VARIATION Gregory J. Nowacki,1 Douglas W. MacCleery,2,3 and Frank K. Lake4 1 USDA Forest Service, Eastern Regional Office, Milwaukee, WI, USA USDA Forest Service, Washington Office, Forest Management (retired), Washington, DC, USA 3 Alexandria, VA, USA 4 USDA Forest Service, Pacific Southwest Research Station, Redding, CA, USA 2 Historical Environmental Variation in Conservation and Natural Resource Management, First Edition. Edited by John A. Wiens, Gregory D. Hayward, Hugh D. Safford, and Catherine M. Giffen. © 2012 John Wiley & Sons, Ltd. Published 2012 by John Wiley & Sons, Ltd. 76 Native Americans, ecosystem development, and historical range of variation 6.1 INTRODUCTION In North America, human beings have not always been considered “legitimate players” in natural ecosystems, often being dismissed as irrelevant, unnatural, or simply “noise” in the system. This is in contrast to the continents outside the Americas, where human history is very long and disentangling human history from ecosystem history is essentially impossible, not to mention nonsensical (Bakker et al. 2000; Jackson & Hobbs 2009). The debate over whether humans are natural parts of North American ecosystems lingers today (Comer 1997; Haila 1997; Hunter 1997), but in our view, it is imperative to include humans in discussions of the ecological past, recognizing that human influences on ecological history vary from significant to slight depending on the location and time frame (Vale 2002). In this chapter, we describe the relative importance of human effects on past ecosystems in North America and, in light of the evidence, discuss the relevance of human history to the historical range of variation (HRV) concept. A spectrum of human– environmental relations is discussed, including human predation on wildlife populations, and the effects of deliberate burning and agriculture/horticulture on vegetation. Human–environmental relations vary among ecosystems and cultures and are illustrated for a representative set of ecoregions across the United States. 6.2 HUMAN ENTRY INTO THE “NEW WORLD ” Throughout the Pleistocene, North American ecosystems reorganized rhythmically with glacial cycles roughly every 100 000 years, driven by an array of processes absent of humans (Pielou 1991; Delcourt 2002). The mix of drivers changed at the end of the last glacial period when human arrival ushered in the Holocene Epoch. Most Native Americans are the direct descendants of northeast Asians (Meltzer 2003) who entered the New World via the Bering Land Bridge approximately 17–22 000 years ago (Mann & Hamilton 1995). Upon arrival, humans brought with them three key things that would profoundly change the American landscape: (1) tools (including weapons), (2) dogs (Fiedel 2005), and (3) fire (Stewart 2002). Populations pooled in Eastern Beringia (Alaska and Yukon Territory), a cul-de-sac of sorts, until ice sheet 77 retreat sometime between 13 000–14 000 years ago (Mann & Hamilton 1995; Meltzer 2003). Once south of the glacial barriers, migrants dispersed swiftly across America, most likely in waves of genetically and linguistically divergent tribal groups (Rogers et al. 1990). For instance, one of the early cultures, the Clovis, may have expanded across North America in as little as 200 years (Waters and Stafford 2007). The Clovis peoples had the traits of big-game hunters, coupling a diverse toolkit, including fire and large-fluted projectiles, with high mobility and broad habitat use. Megafauna (large animals like mammoths [Mammuthus], mastodons [Mammut], and ground slouths [Megatherium and Eremotherium]) were preferentially sought as food. As conspicuous targets on the landscape that left abundant signs of their presence (trails, dung, and broken branches), megafauna could be pursued with relative ease, even as their numbers dwindled (Haynes 2002). Aided with dogs, the ability to track, engage, and slay megafauna and transport meat from kill sites would have made Clovis groups incredibly efficient and lethal hunters (Fiedel 2005). Because of all these factors, the Clovis cultures have been implicated in Late Pleistocene megafaunal extinctions (Haynes 2002). Megafaunal extinction at the hands of humans The extinction of megafauna was an exceptional ecological event with consequences still reverberating through ecosystems today. A total of 34 megafaunal genera went extinct in North America in the Late Pleistocene, including all mammals larger than 1000 kg (Koch & Barnosky 2006). Numerous hypotheses have been advanced to explain megafaunal extinction in North America (Koch & Barnosky 2006). One of the more durable explanations was offered by Martin (1967), entitled the “Pleistocene overkill” theory. Since initially proposed, this human-based extinction hypothesis has endured scientific debate with ongoing research and changing philosophies (Grayson & Meltzer 2003; Fiedel & Haynes 2004). Skeptics claim that severe climatic reversals and associated vegetation shifts during the Pleistocene-Holocene transition were to blame. But then, why were megafauna able to survive numerous prior glacial-to-interglacial transitions only to succumb in the last one? The only apparent difference was human presence. Human-based 78 Issues and challenges extinctions are not unprecedented, having occurred across the globe over millennia (Martin & Steadman 1999; Koch & Barnosky 2006). Extinction across a range of animals, from grazers to browsers and generalists to specialists, strongly argues against climate-based vegetation shifts as the probable cause, but is wholly consistent with humanhunting models (Owen-Smith 1987; Koch & Barnosky 2006). Humans affected megafauna directly (hunting) and indirectly (through competition and habitat alteration) in the midst of postglacial climate change. Changing climate and habitat conditions may have added stress to megafauna populations, but it was humans who ultimately did them in (Haynes 2002). Without human predation, it is unlikely that a Late Pleistocene mass extinction would have occurred (Koch & Barnosky 2006). 6.3 ECOSYSTEMS AFTER MEGAFAUNA – HUMANS BEGIN TO TAKE CONTROL Megaherbivores were the keystone species of their time, disproportionally affecting their environs and embedded food webs. Their ability to radically transform landscapes, open forest and shrub canopies, and promote habitat diversity influenced a multitude of animals at all trophic levels (Owen-Smith 1987). Large proboscideans (mammoths and mastodons) were particularly adept at habitat modification through grazing, browsing, trampling, and wallowing. Megaherbivore extinctions rippled through the animal kingdom, causing further population reductions, food web collapses, and extinctions among animals dependent on megafaunal activities or presence. Openland-dependent, nonmigrating animals and large carnivores and scavengers were most vulnerable (Haynes 2002). As Johnson (2009, p. 2509) aptly states, “big herbivores have big effects on plants” and thus on community composition, structure, and patterns. Some North American trees such as honey locust (Gleditsia triacanthos), hawthorns (Crataegus), mesquite (Prosopis), and Osage-orange (Maclura pomifera) still carry obsolete megaherbivore defenses in the form of stout thorns (Johnson 2009; Bronaugh 2010). Upon extinction, many megaherbivore-limited food sources suddenly became plentiful (Janzen & Martin 1982); the liberation of preferentially browsed trees, especially hardwoods, is clearly seen in the pollen record (Gill et al. 2009). Conversely, anachronistic species reliant on megaherbivores for seed scarification and dispersal declined, including Kentucky coffee tree (Gymnocladus dioicus), honey locust, Osage-orange, pawpaw (Asimina triloba), and persimmon (Diospyros virginiana) (Janzen & Martin 1982; Barlow 2001). In the post-megafauna world, the trajectories of ecosystem development were markedly different than any preceding interglacial period (Johnson 2009; Bronaugh 2010), leading to a complete reorganization of vegetation with new species assemblages and food webs. From this standpoint alone, humans have profoundly affected ecosystem development across the Americas since the onset of the Holocene. Humans and fire What characteristic best differentiates humans from other species: language, intelligence, use of tools? Some would argue it is the use of fire, as no other species has been able to master it (Goudsblom 1987). Fire is an important evolutionary force – a force that humans have used to shape environments across the globe (Sauer 1975; Bond & Keeley 2005). The domestication of fire was intrinsic to the development and spread of human culture, dating back at least 100 000 years and possibly over 1 million years (Bowman et al. 2009; Pausas & Keeley 2009). Invariably during this period, where there was man, there was fire (Sauer 1975; Pausas & Keeley 2009). The people traversing the cold Arctic environments surely brought fire technologies to North America. The spread of fire- and weapon-toting humans across North America left an indelible mark on the paleoecological record. Disturbance regimes changed from megaherbivory to human-based fire. The rise of fire (as measured in charcoal) commensurate with megafauna decrease (measured in dung fungal spores) is reported throughout North America (Davis & Shafer 2006; Gill et al. 2009). An increase in fire may have compensated for ecological changes expected from declines in herbivory, as fire can be considered an “herbivore” of sorts (see Bond & Keeley 2005). The switch from megaherbivory to a human-mediated fire regime led to a new set of plant communities, resulting from the rebound of plants formerly suppressed by herbivory (relaxation), reduction of anachronistic plants, and the promotion of fire-adapted plants (Gill et al. 2009; Johnson 2009). Native Americans, ecosystem development, and historical range of variation The rise of agriculture An extensive switch in human diet ensued after megafaunal extinction. Human population in North America likely declined responding to the combined loss of a significant food source (megafauna) and deterioration of climate during the Younger Dryas. After megafaunal extinction, people switched to smaller Folsom points designed for smaller prey. Subsistence technologies diversified, allowing for greater utilization of resources, especially plants. With the advent of agriculture about 5000 BP, eastern North America became one the five major centers of independent agricultural development in the Americas (Smith & Yarnell 2009). During this time, people transitioned from highly mobile huntergatherers to more sedentary, agriculture-based societies (at least in those areas that supported agriculture). By 3800 BP, agriculture in the eastern United States had become more intense, sophisticated, and responsible for an increasing share of total human nutrition. Human societies responded by growing and becoming more complex. Agrarian lifestyles flourished in warmer, more productive southern portions of the continent. Especially after 800 AD, Three Sister agriculture (composed of maize [Zea], beans [Phaseolus], and squash [Cucurbita]) arose in southeastern North America, eventually spreading to many parts of what is now the United States by the sixteenth century. Across all cultural phases of the Holocene, fire continued to be a key tool in food acquisition, especially in maintaining open habitats, fostering berry- and nutproducing shrubs and trees, game hunting, and land clearance for gardening and habitation (Doolittle 2000; Williams 2000; Abrams & Nowacki 2008). Upon their arrival along the coasts, Europeans did not “discover” an untrammeled wilderness but rather a kaleidoscope of ecosystems reflecting the many native peoples who lived there (Heizer 1978; Patterson & Sassaman 1988; Suttles 1990). Europeans found the preconditioned landscapes (old Indian villages, gardens, and fire-maintained clearings) most suitable for settlement as they afforded the best chances for survival (Mann 2005). Such locations were often the most productive and geographically strategic on the landscape. Butzer (1990, p. 27) wrote that in North America, there existed “a pre-European cultural landscape, one that represented the trial and error as well as the achievement of countless human generations. It is upon this imprint that the more familiar Euro- 79 American landscape was grafted, rather than created anew.” 6.4 HUMAN-MODIFIED LANDSCAPES AT THE EVE OF EUROPEAN CONTACT By the time Europeans arrived in America, indigenous peoples had occupied the continent for many millennia. Human effects on North American landscapes were pervasive in the most productive regions (Southeast, West Coast) and limited in the least productive regions such as the boreal North and interior West (Pyne 1982; Patterson & Sassaman 1988; Vale 2002). Pre-European population density would appear to be a good proxy for human ecological impact. Tribal cultures were an integral part of productive landscapes, serving as active change agents who intentionally managed resources (Stewart 1963; Nicholas 1988). Native Americans affected ecosystem development in enumerable ways, including hunting, gathering, fishing, agriculture, arboriculture (active planting and dissemination of desired woody species), wood gathering, village and trail construction, and habitat manipulation (Williams 2000; Abrams & Nowacki 2008). Fire was used for many of the aforementioned activities, ultimately being the tool of choice to manage landscapes for many socioeconomic benefits (Pyne 1983; Williams 2000). Through examples spanning North America from east to west, the remainder of this chapter illustrates the diverse and often profound influence Native Americans had on ecosystems across the continent. We geographically organize our review of historical human effects on ecosystems, using standard ecological divisions of North America as a template (Cleland et al. 2007; Fig. 6.1). Eastern North America A large percentage of global vegetation does not reflect climax conditions set by climate, but rather represents subclimax conditions largely driven by fire (Bond et al. 2005). This was certainly the case in the eastern United States where fire-dependent communities, such as tallgrass prairies and oak (Quercus), pine (Pinus), and oak-pine woodlands, dominated at the time of European contact (Frost 1993; Hamel & Buckner 1998; Nowacki & Abrams 2008). These principally 80 Issues and challenges Marine Mediterranean Warm Continental Temperate Desert Hot Continental Temperate Steppe Subtropical Tropical/Subtropiacl Desert Savannah Tropical/Subtropiacl Steppe Prairie N 0 250 500 1000 km Fig. 6.1 Ecological Divisions of the continental United States (source: Cleland et al. 2007). open vegetation types sharply contrast with the closedcanopy broadleaf forests that would have otherwise prevailed (Bond et al. 2005). Fire was the principal mechanism controlling vegetation expression in the East, as without it most forested systems would have been composed of late-successional species such as hemlock (Tsuga), fir (Abies), maple (Acer), basswood (Tilia), beech (Fagus), and magnolia (Magnolia). Fires were largely attributed to Native Americans as most were dormant season burns when lightning was at a minimum (Barden 1997; Lorimer 2001; Abrams & Nowacki 2008). Moreover, once started, Native Americans had little incentive or means to put fires out, hence explaining the large spatial extent of firedependent ecosystems across the East. At earliest European contact, human modifications of landscapes were not uniform along the East Coast, but followed a north-south productivity and human population gradient (Driver & Massey 1957; Patterson & Sassaman 1988). In the far north, Native Americans were more oriented to hunting, fishing, and gathering since the cool, short growing season was less conducive to agriculture. The low carrying capacity of the land restricted human populations, and in turn their environmental effects. One exception was wild rice (Zizania) husbandry, which thrived within this lake- Native Americans, ecosystem development, and historical range of variation studded region. There is some evidence that maize consumption and possible cultivation took place in the southern portions of the boreal forest, but again environmental effects would have been minimal (Boyd & Surette 2010). Human ignitions only supplemented the principally lightning-based fire regime. Warm Continental Division: conifer-northern hardwood systems Land impacts were more conspicuous where boreal conifers intermingled with temperate broadleaf trees (Warm Continental Division, Fig. 6.1), although effects were primarily confined to areas around villages, encampments, and trails (Campbell & Campbell 1994; Clark & Royall 1995). Here, the prevailing cool and moist climate coupled with the pyrophobic hardwoods (wet, flaccid leaf litter) greatly suppressed fire, thwarting human’s most potent land-altering tool. Consequently, Native Americans focused on smaller, more manageable burns immediately surrounding their river- and lake-side villages, creating disturbance patches or cultural “islands” within a sea of climax northern hardwoods (Table 6.1; Mann et al. 1994). Western New York and northwestern Pennsylvania are representative, where small clearings and oakdominated forests occurred in areas previously occupied by the Iroquois, especially along rivers and pathways (Ruffner & Abrams 2002; Black et al. 2006). Here, the small and localized effects of Native Americans were reflected in land surveys, with activities recorded on <1% of the bounds surveyed in the 1790s; since this land survey followed Iroquois depopulation, this estimate is biased low but remains an indication of the relatively small human footprint (Marks & Gardescu 1992). The amount of land disturbance undoubtedly oscillated over time contingent with Native American movements and population levels (Ruffner & Abrams 2002; Stambaugh & Guyette 2006). The intensity of human impacts radiated from cultural centers in concentric rings, with fields within 1 km, fuelwood collection and burning for berry production within 4–5 km, and foraging and small game hunting within 6–8 km (Williams 1989; Black et al. 2006). One string of villages along the shores of Green Bay (Wisconsin) is illustrative of the human footprint on the northern hardwood matrix (Dorney & Dorney 1989). Here, Potawatomi and Winnebago peoples established an agricultural-horticultural landscape of 81 fields, open lands, and oak savannas and forests. Burning apparently created these vegetation conditions as soils, topography, or climate did not appreciably differ between the human-modified locale and the distal northern hardwoods. Similar impacts were found in southern Ontario (Clark & Royall 1995; Munoz & Gajewski 2010), where the Native American footprint probably did not exceed 3.2% of the total land base (Campbell & Campbell 1994). At Crawford Lake, sediment analysis showed that increases in charcoal corresponded with increases of fire-dependent pine (Pinus) and oak (Quercus), the appearance of maize, weedy grasses, and purslane (Portulaca) (distinct cultural markers), and decreases of maple and beech from ca. 1350 to 1650 AD. Burning was cited as the primary factor in converting northern hardwoods to open systems of pine and oak. Furthermore, human ignitions have been implicated in the extension of oak-hickory forests up major river valleys along the southern margin of northern hardwood system (Cogbill et al. 2002; Black et al. 2006). Acorns were a highly prized, storable carbohydrate source that supplemented Native American diets, motivating land disturbances that promoted oak and associating species (e.g. blueberries) within the northern hardwood complex (Abrams & Nowacki 2008). Dunham (2009) found archeological sites disproportionally associated with oak habitats in the eastern Upper Peninsula of Michigan. Overall, human land alterations promoted biological and landscape diversity and certainly increased the abundance of shade-intolerant, fire-adapted, and culturally important plants in these Northwoods. Hot Continental Division: central and Appalachian hardwoods Human land modifications flourished south of the cool northern hardwood system where much of the area was either directly or indirectly under Native American control. The favorable climate of the Hot Continental Division (Fig. 6.1) supported agriculture and acorn- and nut-based cultures. Catchment analysis revealed that local cutting and burning practices (for agriculture, fuelwood, and construction materials) increased the representation of hickory (Carya), walnut (Juglans), and black locust (Robinia pseudoacacia) (Black & Abrams 2001), whereas broadcast burns led to the dominance of oak (Quercus), hickory, and American 82 Issues and challenges Table 6.1 Probable climax vegetation versus actual dominant vegetation at the time of European settlement by Ecological Division. Division Climax vegetation1 Dominant presettlement vegetation2 Native American Influence3 Warm Continental Hot Continental Conifer-northern hardwoods Mixed mesophytic forests Conifer-northern hardwoods Oak and oak-pine woodlands Subtropical Beech-magnolia forests Southern pine woodlands Prairie Mixed mesophytic and oak forests Tallgrass prairie Temperate Steppe Shrublands Short and mid-grass prairie Temperate Desert Sagebrush-grass, ponderosa pine, and shade-tolerant conifers Shrublands and pinyonjuniper Sagebrush-grass and ponderosa pine Local; limited to settlements and travel corridors Widespread; landscape burns through Native American ignitions Widespread; landscape burns through Native American ignitions Ubiquitous; prairies wholly dependent on Native American burning Widespread; Native American ignitions increased fire frequency to help support grasses Local to widespread (depending on terrain) Tropical/ Subtropical Desert/Steppe Marine Mediterranean Grasslands and pinyonjuniper Western hemlockDouglas-fir forests Douglas-fir forests Mixed conifer-oak forests Oak woodlands and chaparral Local; effects concentrated on the most productive areas Local; prairies and shrublands maintained by Native American burning. Widespread; open communities maintained by Native American burning 1 Postulated climax vegetation (uplands) in accordance with the disturbance regime without humans. Actual dominant vegetation (uplands) in accordance with the disturbance regime with humans. 3 Stewart (2002), Abrams and Nowacki (2008), Williams (2000), and references therein. 2 chestnut (Castanea) over much of the surrounding landscape (Delcourt & Delcourt 1997; Nowacki & Abrams 2008). Without human-based fire, much of the region would have been dominated by shadetolerant mesophytic trees, such as maple, beech, and basswood (Lorimer 1992; Table 6.1). Interestingly, the interface between oak-dominated ecosystems of this division and the northern hardwood ecosystems to the north was probably more of a function of anthropogenic fire than climate (Cogbill et al. 2002). Descriptions of the open character of this region were very common in the notes of early observers. John Smith commented that around Jamestown, Virginia “a man may gallop a horse amongst these woods any waie, but where the creekes and Rivers shall hinder” (Williams 1989, p. 44). Andrew White, on an expedition along the Potomac in 1633, observed that the forest was “not choked with an undergrowth of brambles and bushes, but as if laid out in by hand in a manner so open, that you might freely drive a four horse chariot in the midst of the trees” (Williams 1989, p. 44). Such observations of the open nature of oak forests from the East Coast through the Ozarks are typical of those of most early observers, who commonly spoke of the ease of riding a horse or driving a wagon under a park-like canopy. A mix of grasslands and open woodlands was maintained specifically for game, an important protein source for indigenous peoples (Abrams & Nowacki 2008). There is evidence that Native Americans were Native Americans, ecosystem development, and historical range of variation encouraging the eastward migration of bison (Bison bison) through habitat manipulation at the time of European contact (Rostlund 1960; Pyne 1982). Sizable grasslands surrounded by oak-dominated woodlands once existed here. In Kentucky, a vast grassland on the Pennyroyal Plateau measured approximately 249 km (155 m) long and 19 km (12 m) wide (Lorimer 2001). In Virginia, the Shenandoah Valley was one vast grass prairie covering more than 2590 sq km (1000 sq mi) where Native Americans burned annually (Van Lear & Waldrop 1989). After burning by indigenous peoples ceased, much of this area reverted to forest and the early white settlers had to clear land that had only recently been prairie (Rostlund 1957). R.C. Anderson (1990, p. 14) writes that the eastern prairies and grasslands “would mostly have disappeared if it had not been for the nearly annual burning of these grasslands by the North American Indians.” Indeed, the existence of the Prairie Peninsula (Prairie Division; Fig. 6.1) in the humid East is thought to be largely an artifact of Native American burning (Anderson 2006). Where not plowed or pastured by Europeans, the open character of the land quickly reverted to dense, closedcanopy oak forests due to fire suppression. Under today’s subdued fire regime, these oak forests are undergoing mesophication and converting to climax forests of shade-tolerant maple, beech, and elm (Ulmus) with little understory diversity (Table 6.1) (Nowacki & Abrams 2008). Subtropical Division: southern pines and associated ecosystems At the time of European contact, the ecological effects of indigenous peoples were likely more significant in the Southeast than anywhere else in North America. This was due to relatively high population densities (Williams 1989), the widespread application of agriculture, as well as plant communities and climatic conditions that facilitated human use of fire. It is difficult to accurately determine ecological conditions at European contact (1500 AD) as there were few European observers in this region at that time. One of the most important was the Hernando de Soto expedition. From 1539 to 1542, de Soto (with his 600 men, 200 horses and 300 swine) pillaged, plundered, and inadvertently spread European diseases from Florida to North Carolina, west across the Mississippi River, then down to the Gulf of Mexico (Thomas et al. 1993; Mann 83 2005). Even with its large numbers of men and animals, the de Soto expedition moved with relative ease throughout the Southeastern landscape, and chroniclers wrote of expansive agricultural fields, open park-like forests, numerous villages, and large numbers of people (Swanton 1939; Rostlund 1957). In what is now Alabama, a de Soto chronicler reported that the land was “so fertile and thickly populated that on some days the Spaniards passed 10 or 12 towns, not counting those that lay on one side or the other of the road” (Rostlund 1957, p. 385). Upon arriving at the Mississippi River, de Soto found a landscape teeming with humans. The river itself was lined with villages (Mann 2005). Eerily, by the time the next explorer passed through this area more than a century later (La Salle in 1682), the entire valley had been radically transformed into a relatively silent place (Mann 2005). Where de Soto had observed scores of villages, expansive agricultural fields, and high human populations, La Salle found mostly forest with very few people or villages. The country had been depopulated (80– 95%) by European diseases, and the ecology of the area substantially altered (Young & Hoffman 1993; Mann 2005; Scharf 2010). Landscapes cleared for agriculture or routinely burned had two or more centuries to recover before the first waves of permanent Euro-American settlers arrived to find landscapes that were more “pristine” than they had been in more than a thousand years (Denevan 1992; Scharf 2010). In addition to the rapid succession of extensive old fields, the depopulation of indigenous peoples undoubtedly led to changes in wildlife populations as a major predation source was substantially reduced. For instance, bison expanded as far south as Florida and as far east as Virginia and Pennsylvania; the large numbers of bison transformed many areas as they grazed, creating large wallows and well-worn migration corridors, some of which remain visible today (Rostlund 1960; Belue 1996). Eyewitness reports describing ecological conditions in the Southeast become more common after 1600 (Smith 1616; Lindestrom 1656, Lederer 1672, Catesby 1731; Bartram 1791). Many of these writers noted extensive “ancient” Indian plantations and abandoned fields extending for kilometers along rivers (see in particular Bartram 1791). The most common ecological conditions reported by these observers were open forests, interspersed with grasslands and meadows, with extensive cane lands along the rivers. Bartram’s journals contain numerous references to “delightful 84 Issues and challenges groves” of open grown “stately forests” of oak, ash, hickory, walnut, and so on, as well as “vast open forests” (Bartram 1791). References to dense forests of late successional species are rare indeed. Rostlund (1957, p. 408) concludes that “the open, parklike appearance of the woodlands, undoubtedly the most common type of forest in the ancient Southeast, was mostly the work of man.” Frequent forest burning did more than create open stands of shade-intolerant trees, but created grasslands where forests would have otherwise existed. There are many references to treeless areas in the early literature, which were often referred to as “barrens,” “plains,” “meadows,” or “savannahs.” In Bartram’s journal, there are numerous separate references to “vast meadows,” “extensive savannas,” and “large grassy plains,” some of which were reported to be many kilometers in length (Rostlund 1957). Bartram reported that the Alachua Savanna in northern Florida was “a level green plain, above 15 m (24 km) over, 50 m (80 km) in circumference, with scarcely a tree to be seen” (Rostlund 1957, p. 408). Canebrakes were also a major feature of Southern bottomlands at the time of European settlement (Platt & Brantley 1997). Indigenous people valued cane for food, shelter, baskets, and tools, especially weapons (Hamel & Chiltoskey 1975). William Bartram repeatedly remarked on canebrakes during his southeastern travels, describing “vast cane meadows,” “widespread cane swamps,” or “an endless wilderness of canes” (Platt & Brantley 1997, p. 10). The area of canebrakes declined rapidly in the eighteenth century from altered disturbance regimes by Euro-Americans, including cattle grazing, agricultural displacement, and changes in fire frequency. Today, cane has been virtually eliminated from the Southeastern landscape and is a contributing factor in the extinction of Bachman’s warbler (Vermivora bachmanii) (Remsen 1986). At the time of European contact, the Coastal Plain was dominated by open stands of large pines (Bartram 1791). Within the range of the fire-tolerant longleaf pine, which covered about 37 million hectares, firesensitive southern mixed broadleaved forests (beech, magnolia, semi-evergreen oaks) were restricted to moist, fire-protected locations (Frost 1993). In the southern portion of longleaf pine distribution, summer lightning fires were sufficient to maintain longleaf pine (Komarek 1964), but burning by indigenous people likely contributed to range extension of longleaf and other southern pines into topographically dissected areas where it would not otherwise have occurred (Frost 1993). By the early 1990s, Frost (1993) estimated that about 1 million hectares remained in naturally regenerated longleaf pine, with only about 270 000 ha (<0.7% of the original range) in a condition similar to the classic open-grown, fire-maintained, longleaf pine-wiregrass community. Like canebrakes, the longleaf pine/wiregrass community is currently considered a critically endangered ecosystem (Noss et al. 1995). The Great Plains and interior west Native American populations became progressively more sparse west of the Mississippi River across the Great Plains (Temperate Steppe Division) through the Rocky Mountains (Temperate Desert Division; Fig. 6.1), essentially following an aridity gradient. Together with changes in topography, Native American– environmental relations varied broadly across this western expanse. The relatively flat and seasonally dry conditions in the center of the continent were naturally conducive to extensive fire. The vast grasslands that epitomized the Great Plains were promulgated by frequent surface burning (Wright & Bailey 1980), and fed large ungulates such as bison, elk (Cervus canadensis), deer (Odocoileus), and later horses (Equus). Ungulate populations were regulated by hunting where denser Native American populations existed, perhaps to the point of being largely relegated to the outskirts of tribal territories (Martin & Szuter 1999; Kay 2007). Well versed in prey–habitat relations, indigenous peoples promoted preferred habitat conditions through burning and were the principal igniters outside the thunderstorm season (April to September) when optimal fuel conditions (dry grass) existed. Without the addition of human ignitions, the Great Plains may have been substantially shrubbier, supporting fewer large herbivores (Arno & Gruell 1983; Stewart 2002; Table 6.1). Post-European agriculture, grazing, and fire suppression adversely affected the species composition and diversity of the Great Plains. In the Rocky Mountains (Temperate Desert Division), resources important to indigenous peoples were geographically spread from river valley to alpine meadow. Evidence suggests that management of resource patches by indigenous people was common, although at decreasing intensity with elevation (Barrett & Arno 1982; Hessburg & Agee 2003). Many tribes practiced Native Americans, ecosystem development, and historical range of variation seasonal rounds, migrating to higher elevations during the summer, and back to winter villages in the lowlands. Along the way, both the flora and fauna of these mountainous ecosystems were affected by Native American hunting, plant gathering, and burning. Early observations of western fires compiled by Gruell (1985) revealed that many were set by indigenous peoples, especially at lower and middle elevations. Here, intentional burning helped create and maintain a mosaic of stand conditions across the landscape. Periodic burning helped promote root and berry crops, materials for basketry, forage for prey animals, and improved visibility for hunting (Stewart 2002). However, given the inherent severity of mountain and high desert environments (rugged topography, short growing seasons, temperature extremes, snow, and aridity), Native Americans probably had a much lighter touch in this region relative to other, more productive areas of North America (Vale 2002). Nevertheless, human ignitions were embedded in historical fire regimes that supported a diverse vegetation mosaic – a mosaic now being unraveled by fire suppression (Pyne 1982; Arno & Gruell 1983; Brown & Hull-Sieg 1996). Repeat photography clearly shows the dramatic recent increases in forest cover in many western landscapes (Progulske 1974; Gruell 1983; Skovlin & Thomas 1995). West Coast Marine Division: temperate rainforests Lightning has been accepted as the main ignition source of fires in this topographically diverse region, with frequency of strikes increasing with distance from coast and with elevation (Agee 1993; van Wagtendonk & Cayan 2008). Fires of the mesic forests in Coast Ranges and Cascades were infrequent, stand-replacing, highseverity events (Agee 1993; Lertzman et al. 2002), although mixed severity and more frequent lowmoderate severity fire regimes existed in mixed coniferhardwood vegetation and grassland communities (Agee 1993; Weisberg & Swanson 2003; Taylor et al. 2008). Where summer lightning fires were not adequate to foster and maintain the desired condition, tribal burning was used. The extent to which Native American fires affected historical fire regimes of these mesic coniferdominated forests is debated (Agee 1993; Boyd 1999). The longevity and extent of burning practices by diverse tribal groups across the Pacific Northwest and 85 California is not clear from archeological interpretations (Ames & Maschner 1999; Boyd 1999). Late Holocene tribal groups did not practice sedentary agriculture, but rather a proto-agriculture/horticulture integrated with fire regimes (Lewis 1993; Boyd 1999). Vegetation nearest villages, trail systems, and remote resource collection areas (i.e. camps) was selectively modified by altering the frequency, seasonality, and extent of fires (Boyd 1999). Cultural practices sought to increase wildlife forage, root, seed, nut, and berry crops, enhance basketry materials, and improve hunting opportunities (Boyd 1999). Mediterranean Division: oak balanocultures Across the major mountain ranges and valleys of California, the establishment and increased abundance of oaks (Quercus and Lithocarpus) took place in the MidHolocene approximately 9000–10 000 years ago (West et al. 2007; Briles et al. 2008). Oaks likely reached their present distribution during the Late Holocene (West et al. 2007). Frequent lower intensity fires promoted oakdominated habitats. Dendroecological studies indicate that fires occurred primarily during the summer seasonal drought, typical of the lightning ignitions (van Wagtendonk & Fites-Kaufman 2006). However, there is also evidence of spring burns, which suggests human ignitions (Skinner et al. 2009). Estimates of precontact (circa 200 years BP) firereturn intervals range from annual to decadal events for Oregon white oak/grassland communities (McDadi & Hebda 2008), and from 5 to 20 years for mixed oak/ conifer-hardwood forests of California (Skinner & Taylor 2006). Charcoal and pollen analyses suggest a reduction in fire frequency during European settlement (McDadi & Hebda 2008), leading to the conversion of oak-dominated savannas to closed-canopy forests of more mesic, fire-sensitive species. This change occurred despite broad climatic similarity between pre- and postEuropean eras (Byrne et al. 1991). The rapid change in grassland/oak vegetation coincident with European settlement during a relatively stable climate provides a striking contrast to the persistence of grassland/oak vegetation over long periods of variable climate during Native American management. Subsistence economies (DeLancey & Golla 1997) associated with oak grasslands remained fairly constant over the last 2500 years in the Sacramento and 86 Issues and challenges San Joaquin valleys (Elasser 1978). Those tribal groups inhabiting inland oak/grass-dominated valleys are thought to have been deliberately broadcast-burning vegetation by 3000, if not 5000 years BP (Weiser & Lepofsky 2009). Archeological evidence indicates the majority of nonmarine/littoral-adapted tribal groups developed important associations with oak-dominated habitats. Milling stones and related lithic tools (e.g. mortars and pestles) used for processing seeds, nuts, or other foods by tribal groups suggest an adaption to use acorns as early as 7000 years ago in the California North Coast Range and 4000 years BP in the San Francisco Bay Area, Sacramento Valley, and southern California (Elasser 1978; Keeley 2002; Arnold et al. 2004). By 1300 years ago, acorns were a cultural mainstay in the Sacramento/San Joaquin Valleys and in southern California (Elasser 1978; Arnold et al. 2004). The bow and arrow was introduced by 1500–2000 years ago, and coincides with other technological changes (e.g. mortars and pestles) associated with diversified subsistence economies (acorns, roots, seeds/nuts, fish, game, etc.). The use of fire by tribal groups to promote oak dominance coincided with the need to counteract natural successional tendencies, and the need to maintain tribal economies dependent on oaks and associated species that provided valued food, materials, and medicines; various tribal groups exhibited proprietor claims to tracts of oaks and associated resources (game and bulbs/roots) within these habitats (Anderson 2007; McDadi & Hebda 2008). Inland areas codominant with oaks, and especially traversable ridge systems with southern exposure, were kept open through burning by tribal groups that depended on resources found in early seral oak grasslands (Boyd 1999; Keeley 2002). A combination of biophysical conditions and tribal burning likely fostered oak dominance and persistence. It is unknown just how much of the oak-dominated landscape was influenced by tribal burning (Boyd 1999; Anderson 2007). Oak habitats have greatly declined since Euro-American settlement due to the cessation of tribal burning, grazing of livestock, fire suppression, industrial forestry practices (favoring conifers), and urbanization (Hosten et al. 2006; Anderson 2007). 6.5 NATIVE AMERICANS AND THE HRV CONCEPT Precontact Native American cultures were sophisticated, dynamic, diverse social organizations with indi- viduals who knew how to alter their surroundings for their benefit (Pyne 1983). Since their postglacial arrival, human populations and their scope of influence increased as they dispersed across the Americas, reaching a peak at the time of European contact (Mann 2005; Scharf 2010). By that time, human population density closely paralleled gradients in land productivity, ranging from low to high densities from north to south in eastern North America and from mountains and deserts (low) to fertile valleys and coastlines (high) in the West. As such, the geographical influences of Native Americans were not uniform, but reflected differences in populations, land use, cultural traditions, available resources, climate, and vegetation flammability (Kimmerer & Lake 2001; Stewart 2002; Vale 2002). In North America, literature illustrating the various roles of early humans in environments has not been well integrated into our ecological knowledge. The reasons are many, including historic and cultural biases and political agendas, as well as the challenges associated with obtaining clear scientific evidence of environmental conditions 300 or more years ago (Stewart 1963; Pyne 1982; Williams 2000). The important role humans played was largely overlooked by most early ecologists, who described North American landscape in terms of static “climax” systems consistent with the prevailing philosophy at the time. Early paleoecologists also largely ignored the human factor, tying Holocene species movements and ecosystem reorganization exclusively to climate (Delcourt & Delcourt 2004; Scharf 2010). Shades of this oversight continue today, through our intense focus on climate change, which tends to assume that vegetation (baseline data for climate-change models) is solely reflective of climate. Indeed, a new synthesis is needed integrating ecology, paleontology, and archeology to discern the complex relations between ecosystems and embedded humans (a panarchical approach; Delcourt & Delcourt 2004). Fortunately, the acknowledgment of past humans as an ecological factor is gaining momentum, and is reflected in the use of “historical range of variation” rather than “natural range of variation.” In this regard, humans are essentially acknowledged as the change agents that put the “H” in the HRV concept. The preceding sections chronicle a rich array of Native American influences on ecosystems across time and space, beginning with their continental arrival as the new top predator. By employing weapons, dogs, and efficient hunting strategies, Native Americans proved lethal against an unwary megafaunal prey Native Americans, ecosystem development, and historical range of variation base, and played a leading role in the rapid demise of many large herbivore species. The removal of megaherbivores had a liberating effect on plant life (especially trees) in the midst of postglacial revegetation of the North American continent. Native Americans also represented a new ignition source – an ever-constant source of flame that was less constrained (spatially, seasonally) than natural ignitions (Stewart 2002; Abrams & Nowacki 2008). Fire ultimately became the most powerful tool for landscape manipulation (Sauer 1975; Kimmerer & Lake 2001), which Native Americans used with purpose and facility. Later, as huntergatherer societies shifted toward more sedentary lifestyles with growing technology, direct habitat manipulation through agriculture and horticulture took place where climate and soils allowed. Through these three factors alone, Native American impacts spanned spatiotemporal scales from continental (megafaunal demise and subsequent trophic effects; Early Holocene onward) to landscape (broadcast burning; Mid-Holocene onward) to local (agriculture/ horticulture; Late Holocene). Not all human-related ecological disturbances are equally important to HRV analyses. Application of historical ecology generally relies on time-space scales relevant to current land-management decisions, focusing on shorter, more recent periods with relatively stable climates, vegetation, and disturbance regimes at a particular locale. Coupled with inherent data limitations (e.g. a fading data record with time), timelines are often restricted to the last thousand years or less. To help integrate the consequences of Native American land use into HRV analyses, data collection at a minimum should identify and record principal landuse activities associated with former tribal territories. Linking human-based disturbances (type, frequency, intensity) with plant community structure and composition allows a more complete understanding of ecosystem dynamics, further enlightening the science behind restoration. Why is it important to understand the role of indigenous people in ecosystem dynamics described by HRV analyses? Altered disturbance regimes affecting many North American ecosystems may result in unsustainable conditions. The “pristine myth” is an enormous cultural barrier to purposeful human intervention in these systems (Hamel & Buckner 1998). Many wildernesses and protected “natural” areas exhibit vegetation conditions at odds with what would have been expected in pre-European landscapes and are on unprecedented 87 ecological trajectories. Without active human intervention, open woodlands of shade-intolerant species (systems that have dominated many landscapes for millennia) will continue to be replaced by closed forests of shade-tolerant species (Nowacki & Abrams 2008). Developments in historical ecology have improved our understanding of past disturbance regimes, which are vital to predicting vegetation succession and dynamics. Indeed, many rare and endemic plant and animal species in the United States are disturbance dependent, and many of those historical disturbances were associated with Native American activities. A large proportion of the endangered ecosystems listed by Noss et al. (1995) are fire-dominated ecosystems. These include prairies, pine savannahs and barrens, tropical hardwood hammocks, and shrublands. Of 21 rare communities listed in the Ozark-Ouachita Highlands Assessment, the decline of nine was attributed to fire exclusion (USDA 1999). Nationwide, Owen and Brown (2005) found that of 186 federally listed, proposed, and candidate plant species, 25% required fire, 35% tolerated fire, 38% were not affected by fire, and only 2% were adversely affected by fire. Resource managers are largely powerless to counter the ecological effects of the substantial land-use changes that have occurred in North America over the last three centuries. But they are not powerless to recognize and address through management activities the ecological effects of altered disturbance regimes. An understanding of natural and human influences on the development of historical landscapes is critical to effectively planning and executing projects designed to restore or conserve rare and endemic species and ecosystems (Hamel & Buckner 1998; Scharf 2010). Developing an appreciation of the past roles of humans in modifying “natural” ecosystems in North America is also a first step toward better understanding and managing the roles humans will play in future ecosystems. REFERENCES Abrams, M.D. & Nowacki, G.J. (2008). Native Americans as active and passive promoters of mast and fruit trees in the eastern USA. The Holocene, 18, 1123–1137. Agee, J.K. (1993). Fire Ecology of the Pacific Northwest Forests. Island Press, Washington, DC, USA. Ames, K.M. & Maschner, H.D. (1999). Peoples of the Northwest Coast: Their Archaeology and Prehistory. Thames and Hudson, London, UK. 88 Issues and challenges Anderson, M.K. (2007). Indigenous uses, management, and restoration of oaks of the far western United States. Technical Note No. 2. USDA Natural Resource Conservation Service, National Plant Data Center, Greensboro, NC, USA. Anderson, R.C. (1990). The historic role of fire in the North American grassland. In Fire in North American Tallgrass Prairies (ed. S.L. Collins and L.L. Wallace), pp. 8–18. University of Oklahoma Press, Norman, OK, USA. Anderson, R.C. (2006). Evolution and origin of the central grassland of North America: climate, fire, and mammalian grazers. Journal of the Torrey Botanical Society, 133, 626–647. Arno, S.F. & Gruell, G.E. (1983). Fire history at the forestgrassland ecotone in southwestern Montana. Journal of Range Management, 36, 332–336. Arnold, J.E., Walsh, M.R., & Hollimon, S.E. (2004). The archaeology of California. Journal of Archaeological Research, 12, 1–73. Bakker, J.P., Grootjans, A.P., Hermy, M., & Poschlod, P. (eds.). (2000). How to define targets for ecological restoration? Journal of Applied Science, 3, 1–72. Barden, L.S. (1997). Historic prairies in the Piedmont of North and South Carolina, USA. Natural Areas Journal, 17(2), 149–152. Barlow, C. (2001). Anachronistic fruits and the ghosts who haunt them. Arnoldia, 61, 14–21. Barrett, S.W. & Arno, S.F. (1982). Indian fires as an ecological influence in the northern Rockies. Journal of Forestry, 80, 647–651. Bartram, W. (1791). Travels of William Bartram. Dover Publications (1955 ed.), New York, USA. Belue, T.F. (1996). The Long Hunt: Death of the Buffalo East of the Mississippi. Stackhole Books, Mechanicsburg, PA, USA. Black, B.A. & Abrams, M.D. (2001). Influences of Native Americans and surveyor biases on metes and bounds witness-tree distribution. Ecology, 82, 2574–2586. Black, B.A., Ruffner, C.M., & Abrams, M.D. (2006). Native American influences on the forest composition of the Allegheny Plateau, northwest Pennsylvania. Canadian Journal of Forest Research, 36, 1266–1275. Bond, W.J. & Keeley, J.E. (2005). Fire as a global “herbivore”: the ecology and evolution of flammable ecosystems. Trends in Ecology and Evolution, 20, 387–394. Bond, W.J., Woodward, F.I. & Midgley, G.F. (2005). The global distribution of ecosystems in a world without fire. New Phytologist, 165, 525–537. Bowman, D.M.J., Balch, J.K., Artaxo, P., et al. (2009). Fire in the earth system. Science, 324, 481–484. Boyd, M. & Surette, C. (2010). Northernmost precontact maize in North America. American Antiquity, 75, 117–133. Boyd, R. (ed.). (1999). Indians, Fire and the Land in the Pacific Northwest. Oregon State University Press, Corvallis, OR, USA. Briles, C.E., Whitlock, C., Bartlein, P.J., & Higuera, P. (2008). Regional and local controls on postglacial vegetation and fire in the Siskiyou Mountains, northern California, USA. Palaeogeography, Palaeoclimatology, Palaeoecology, 265, 159–169. Bronaugh, W. (2010). The trees that miss the mammoths. American Forests, 115, 38–43. Brown, P.M. & Hull-Sieg, C. (1996). Fire history in interior ponderosa pine communities of the Black Hills, South Dakota, USA. International Journal of Wildland Fire, 6, 97–105. Butzer, K.W. (1990). The Indian legacy in the American Landscape. In The Making of the American Landscape (ed. M.P. Conzen), pp. 27–50. Unwin Hyman, Boston, MA, USA. Byrne, R., Edlund, E., & Mensing, S. (1991). Holocene changes in the distribution and abundance of oaks in California. In Proceedings of the Symposium on Oak Woodlands and Hardwood Rangeland Management; Davis, CA (R.B. Standiford technical coordinator), pp. 182–188. General Technical Report PSW-126. USDA Forest Service, Berkeley, CA, USA. Campbell, I.D. & Campbell, C. (1994). The impact of Late Woodland land use on the forest landscape of southern Ontario. Great Lakes Geographer, 1, 22–29. Catesby, M. (1731). The Natural History of Carolina, Florida, Bahama Islands. Beehive Press, Savannah, GA, USA. Clark, J.S. & Royall, P.D. (1995). Transformation of a northern hardwood forest by aboriginal (Iroquios) fire: charcoal evidence from Crawford Lake, Ontario, Canada. The Holocene, 5, 1–9. Cleland, D.T., Freeouf, J.A., Keys, J.E., Nowacki, G.J., Carpenter, C.A., & McNab, W.H. (2007). Ecological subregions: sections and subsections of the conterminous United States. General Technical Report WO–76 [CD]. USDA Forest Service, Washington, DC, USA. Cogbill, C.V., Burk, J., & Motzkin, G. (2002). The forests of presettlement New England, USA: spatial and compositional patterns based on town proprietor surveys. Journal of Biogeography, 29, 1279–1304. Comer, P.J. (1997). Letters: A “natural” benchmark for ecosystem function. Conservation Biology, 11, 301–303. Davis, O.K. & Shafer, D.S. (2006). Sporormiella fungal spores, a palynological means of detecting herbivore density. Palaeogeography, Palaeoclimatology, Palaeoecology, 237, 40–50. DeLancey, S. & Golla, V. (1997). The Penutian hypothesis: retrospect and prospect. International Journal of American Linguistics, 63, 171–202. Delcourt, H.R. (2002). Forests in Peril: Tracking Deciduous Trees from Ice-Age Refuges into the Greenhouse World. McDonald and Woodward Publishing Company, Blacksburg, VA, USA. Delcourt, H.R. & Delcourt, P.A. (1997). Pre-Columbian Native American use of fire on southern Appalachian landscapes. Conservation Biology, 11, 1010–1014. Delcourt, P.A. & Delcourt, H.R. (2004). Prehistoric Native Americans and Ecological Change. Cambridge University Press, Cambridge, UK. Denevan, W.M. (1992). The pristine myth: the landscape of the Americas in 1492. Annals of the Association of American Geographers, 82, 369–385. Native Americans, ecosystem development, and historical range of variation Doolittle, W.E. (2000). Cultivated Landscapes of Native North America. Oxford University Press, Oxford, UK. Dorney, C.H. & Dorney, J.R. (1989). An unusual oak savanna in northeastern Wisconsin: the effect of Indian-caused fire. American Midland Naturalist, 122, 103–113. Driver, C.H. & Massey, W.C. (1957). Comparative studies of North American Indians. Transactions of the American Philosophical Society, 47, 167–456. Dunham, S.B. (2009). Nuts about acorns: a pilot study on acorn use in Woodland Period subsistence in the eastern Upper Peninsula of Michigan. Wisconsin Archeologist, 90, 113–130. Elasser, A.B. (1978). Development of regional prehistoric cultures. In Handbook of North American Indians, Vol. 8: California (ed. R.F. Heizer), pp. 37–57. Smithsonian Institution, Washington, DC, USA. Fiedel, S.J. (2005). Man’s best friend: mammoth’s worst enemy? A speculative essay on the role of dogs in Paleoindian colonization and megafaunal extinction. World Archaeology, 37, 11–25. Fiedel, S. & Haynes, G. (2004). A premature burial: comments on Grayson and Meltzer’s “requiem for overkill.” Journal of Archaeological Science, 31, 121–131. Frost, C.C. (1993). Four centuries of changing landscape patterns in the longleaf pine ecosystem. In Proceedings of the Tall Timbers Fire Ecology Conference No. 18 (ed. S. Hermann), pp. 17–43. Tall Timbers Research Station, Tallahassee, FL, USA. Gill, J.L., Williams, J.W., Jackson, S.T., Lininger, K.B., & Robinson, G.S. (2009). Pleistocene megafaunal collapse, novel plant communities, and enhanced fire regimes in North America. Science, 326, 1100–1103. Goudsblom, J. (1987). The domestication of fire as a civilizing process. Theory Culture Society, 4, 457–476. Grayson, D.K. & Meltzer, D.J. (2003). A requiem for North American overkill. Journal of Archaeological Science, 30, 585–593. Gruell, G.E. (1983). Fire and vegetative trends in the Northern Rockies: interpretations from 1871–1982 photographs. General Technical Report INT-158. USDA Forest Service, Ogden, UT, USA. Gruell, G.E. (1985). Fire on the early western landscape: an annotated record of wildland fires 1776–1900. Northwest Science, 59, 97–107. Haila, Y. (1997). Letters: a “natural” benchmark for ecosystem function. Conservation Biology, 11, 300–301. Hamel, P.B. & Buckner, E.R. (1998). How far could a squirrel travel in the treetops? A prehistory of the southern forest. In Transactions of the 63rd North American Wildlife and Natural Resources conference, Orlando, FL, pp. 309–315. Wildlife Management Institute, Washington, DC, USA. Hamel, P.B. & Chiltoskey, M.U. (1975). Cherokee Plants and Their Uses: A 400-Year History. Herald, Sylva, NC, USA. Haynes, G. (2002). The catastrophic extinction of North American mammoths and mastodonts. World Archaeology, 33, 391–416. 89 Heizer, R.F. (ed.). (1978). Handbook of North American Indians, Vol. 8: California. Smithsonian Institution, Washington, DC, USA. Hessburg, P.F. & Agee, J.K. (2003). An environmental narrative of Inland Northwest United States forests, 1800–2000. Forest Ecology and Management, 178, 23–59. Hosten, P.E., Hickman, O.E., Lake, F.K., Lang, F.A., & Vesely, D. (2006). Oak woodlands and savannas. In Restoring the Pacific Northwest: The Art and Science of Ecological Restoration in Cascadia (ed. D. Apostol and M. Sinclair), pp. 63–96. Island Press, Washington, DC, USA. Hunter, M. Jr. (1997). Letters: a “natural” benchmark for ecosystem function. Conservation Biology, 11, 303–304. Jackson, S.T. & Hobbs, R.J. (2009). Ecological restoration in the light of ecological history. Science, 325, 567–568. Janzen, D.H. & Martin, P.S. (1982). Neotropical anachronisms: the fruits the Gomphotheres ate. Science, 215, 19–27. Johnson, C.N. (2009). Ecological consequences of Late Quaternary extinctions of megafauna. Proceedings of the Royal Society B: Biological Sciences, 276, 2509–2519. Kay, C.E. (2007). Were native people keystone predators? A continuous-time analysis of wildlife observations made by Lewis and Clark in 1804–1806. Canadian Field-Naturalist, 121, 1–16. Keeley, J.E. (2002). Native American impacts on fire regimes of the California coastal ranges. Journal of Biogeography, 29, 303–320. Kimmerer, R.W. & Lake, F.K. (2001). The role of indigenous burning in land management. Journal of Forestry, 99, 36–41. Koch, P.L. & Barnosky, A.D. (2006). Late Quaternary extinctions: state of the debate. Annual Review of Ecology, Evolution, and Systematics, 37, 215–250. Komarek, E.V. (1964). The natural history of lightning. In Proceedings of the Third Tall Timbers Fire Ecology Conference, pp. 139–183. Tall Timbers Research Station, Tallahassee, FL, USA. Lederer, J. (1672). The discoveries of John Lederer in several marches from Virginia to the west of Carolina and other parts of the continent. Collected and translated by Sir William Talbot (London, 1672); reprint 1902, G.P. Humphry, Rochester NY, USA. Lertzman, K., Gavin, D., Hallett, D., Brubaker, L., Lepofsky, D., & Mathewes, R. (2002). Long-term fire regime estimated from soil charcoal in coastal temperate rainforest. Conservation Ecology, 6(2), article 5. http://www.consecol.org/vol6/ iss2/art5. Lewis, H.T. (1993). Patterns of Indian burning in California: ecology and ethnohistory. In Before the Wilderness (ed. T.C. Blackburn and K. Anderson), pp. 55–116. Ballena Press, Menlo Park, CA, USA. Lindestrom, P. ([1656] 1925). Geographia Americae. (A. Johnson, translator). Swedish Colonial Society, Philadelphia, PA, USA.. 90 Issues and challenges Lorimer, C.G. (1992). Causes of the oak regeneration problem. In General Technical Report SE-84. (ed. D. Loftis and C.E. McGee). USDA Forest Service, Asheville, NC, USA. Lorimer, C.G. (2001). Historical and ecological roles of disturbance in eastern North American forests: 9000 years of change. Wildlife Society Bulletin, 29, 425–439. Mann, C.C. (2005). 1491: New Revelations of the Americas before Columbus. Alfred A. Knopf, New York, USA. Mann, D.H. & Hamilton, T.D. (1995). Late Pleistocene and Holocene paleoenvironments of the North Pacific Coast. Quaternary Science Reviews, 14, 449–471. Mann, D.H., Engstrom, F.B., & Bubier, J.L. (1994). Fire history and tree recruitment in an uncut New England Forest. Quaternary Research, 42, 206–215. Marks, P.L. & Gardescu, S. (1992). Vegetation of the central Finger Lakes region of New York in the 1790s. In Late eighteenth century vegetation of central and western New York State on the basis of original land survey records (ed. C.A. Chumbley), pp. 1–35. Bulletin No. 484. New York State Museum, Albany, NY, USA. Martin, P.S. (1967). Prehistoric overkill. In Pleistocene Extinctions: The Search for a Cause (ed. P.S. Martin and H.E. Wright Jr.), pp. 75–120. Yale University Press, New Haven, CT, USA. Martin, P.S. & Steadman, D.W. (1999). Prehistoric extinctions on islands and continents. In Extinctions in Near Time: Causes, Contexts, and Consequences (ed. R.D.E. MacPhee), pp. 17–55. Kluwer Academic/Plenum Publishers, New York, USA. Martin, P.S. & Szuter, C.R. (1999). War zones and game sinks in Lewis and Clark’s West. Conservation Biology, 13, 36–45. McDadi, O. & Hebda, R.J. (2008). Change in historic fire disturbance in a Garry oak (Quercus garryana) meadow and Douglas-fir (Pseudotsuga menziesii) mosaic, University of Victoria, British Columbia, Canada: a possible link with First Nations and Europeans. Forest Ecology and Management, 256, 1704–1710. Meltzer, D.J. (2003). Peopling of North America. Development in Quaternary Science, 1, 539–563. Munoz, S.E. & Gajewski, K. (2010). Distinguishing prehistoric human influence on late-Holocene forests in southern Ontario, Canada. The Holocene, 20, 967–981. Nicholas, G.P. (ed.). (1988). Holocene Human Ecology in Northeastern North America. Plenum Press, New York, USA. Noss, R.F., Laroe, E.T. III., & Scott, J.M. (1995). Endangered ecosystems of the United States: a preliminary assessment of loss and degradation. Biological Report 28. USDI National Biological Service, Washington, DC, USA. Nowacki, G.J. & Abrams, M.D. (2008). The demise of fire and “mesophication” of forests in the eastern United States. BioScience, 58, 123–138. Owen, W. & Brown, H. (2005). The effects of fire on rare plants. Fire Management Today, 65(4), 13–15. Owen-Smith, N. (1987). Pleistocene extinctions: the pivotal role of megaherbivores. Paleobiology, 13, 351–362. Patterson, W.A. III. & Sassaman, K.E. (1988). Indian fires in the prehistory of New England. In Holocene Human Ecology in Northeastern North America (ed. G.P. Nicholas), pp. 107– 135. Plenum Press, New York. Pausas, J.G. & Keeley, J.E. (2009). A burning story: the role of fire in the history of life. BioScience, 59, 593–601. Pielou, E.C. (1991). After the Ice Age: The Return of Life to Glaciated North America. University of Chicago Press, Chicago, IL, USA. Platt, S.G. & Brantley, C.G. (1997). Canebreaks: an ecological and historical perspective. Castanea, 62(1), 8–21. Progulske, D.R. (1974). Yellow ore, yellow hair, yellow pine: a photographic study of a century of forest ecology. Bulletin No. 616. South Dakota State University, Brookings, SD, USA. Pyne, S.J. (1982). Fire in America: A Cultural History of Wildland and Rural Fire. Princeton University Press, Princeton, NJ, USA. Pyne, S.J. (1983). Indian fires. Natural History, 2, 6–11. Remsen, J.V. (1986). Was Bachman’s warbler a bamboo specialist? Auk, 103, 216–219. Rogers, R.A., Martin, L.D., & Nicklas, T.D. (1990). Ice-Age geography and the distribution of native North American languages. Journal of Biogeography, 17, 131–143. Rostlund, E. (1957). The myth of a natural prairie belt in Alabama: an interpretation of historical records. Annals of the Association of American Geographers, 47, 392–411. Rostlund, E. (1960). The geographic range of the historic bison in the Southeast. Annals of the Association of American Geographers, 50, 395–407. Ruffner, C.M. & Abrams, M.D. (2002). Dendrochronological investigation of disturbance history for a Native American site in northwestern Pennsylvania. Journal of the Torrey Botanical Society, 129, 251–260. Sauer, C.O. (1975). Man’s dominance by use of fire. Geoscience and Man, 10, 1–13. Scharf, E.A. (2010). Archaeology, land use, pollen and restoration in the Yazoo Basin (Mississippi, USA). Vegetation History and Archaeobotany, 19, 159–175. Skinner, C.N. & Taylor, A.H. (2006). Southern Cascades bioregion. In Fire in California’s Ecosystems (ed. N.G. Sugihara, J.W. Van Wagtendonk, K.E. Shaffer, J. Fites-Kaufman, and A.E. Thode), pp. 195–224. University of California Press, Berkeley, CA, USA. Skinner, C.N., Abbot, C.S., Fry, D.L., Stephens, S.L., Taylor, A.H., & Trouet, V. (2009). Human and climate influences on fire occurrence in California’s North Coast Range, USA. Fire Ecology, 5, 76–99. Skovlin, J.M. & Thomas, J.W. (1995). Interpreting long-term trends in Blue Mountain ecosystems from repeat photography. General Technical Report PNW-GTR-315. USDA Forest Service, Portland, OR, USA. Native Americans, ecosystem development, and historical range of variation Smith, B.D. & Yarnell, R.A. (2009). Initial formation of an indigenous crop complex in eastern North America at 3800 B.P. Proceedings of the National Academy of Sciences Early Edition, 106(16), 6561–6566. http://www.pnas.org/ content/early/2009/04/03/0901846106.full.pdf. Smith, J. ([1616] 1905). A description of New England. In Sailors Narratives of Voyages Along the New England Coast 1526–1624 (ed. G.P. Winship), pp. 212–247. HoughtonMifflin (1905), Boston, MA. Stambaugh, M.C. & Guyette, R. (2006). Fire regime of an Ozark wilderness area, Arkansas. American Midland Naturalist, 156, 237–251. Stewart, O.C. (1963). Barriers to understanding the influence of use of fire by aborigines on vegetation. In Proceedings of the Second Tall Timbers Fire Ecology Conference, pp. 117–126. Tall Timbers Research Station, Tallahassee, FL, USA. Stewart, O.C. (2002). The effects of burning of grasslands and forests by aborigines the world over. In Forgotten Fires: Native American and the Transient Wilderness (ed. H. Lewis and M.K. Anderson), pp. 67–338. University of Oklahoma Press, Norman, OK, USA. Suttles, W. (ed.). (1990). Handbook of North American Indians, Vol. 7: Northwest Coast. Smithsonian Institution, Washington, DC, USA. Swanton, J.R. (1939). Final report of the United States De Soto Expedition Commission, House Document. 71, 76th Cong., 1st session, Washington, DC, USA. Taylor, A.H., Trouet, V., & Skinner, C.N. (2008). Climatic influences on fire regimes in montane forests of the southern Cascades, California, USA. International Journal of Wildland Fire, 17, 60–71. Thomas, D.H., Miller, J., White, R., Nabokov, P., & Deloria, P.J. (1993). The Native Americans: An Illustrated History. Turner Publishing, Atlanta, GA, USA. USDA. (1999). Ozark-Ouachita highlands assessment: terrestrial vegetation and wildlife. General Technical Report SRS35. USDA Forest Service, Asheville, NC, USA. Vale, T. (2002). Fire, Native People and the Natural Landscape. Island Press, Washington, DC, USA. 91 Van Lear, D.H. & Waldrop, T.A. (1989). History, uses, and effects of fire in the Appalachians. General Technical Report SE-54. USDA Forest Service, Asheville, NC, USA. van Wagtendonk, J.W. & Cayan, D.R. (2008). Temporal and spatial distribution of lightning in California in relation to large-scale weather patterns. Fire Ecology, 4, 34–56. van Wagtendonk, J.W. & Fites-Kaufman, J. (2006). Sierra Nevada bioregion. In Fire in California’s Ecosystems (ed. N.G. Sugihara, J.W. Van Wagtendonk, K.E. Shaffer, J. FitesKaufman, and A.E. Thode), pp. 264–294. University of California Press, Berkeley, CA, USA. Waters, M.R. & Stafford, T.W. Jr. (2007). Redefining the age of Clovis: implications for the peopling of the Americas. Science, 315, 1122–1126. Weisberg, P.J. & Swanson, F.J. (2003). Regional synchroneity in fire regimes of western Oregon and Washington, USA. Forest Ecology and Management, 172, 17–28. Weiser, A. & Lepofsky, D. (2009). Ancient land use and management of Ebey’s Prairie, Whidbey Island, Washington. Journal of Ethnobiology, 29, 184–212. West, G.J., Woolfenden, W., Wanket, J.A., & Anderson, S. (2007). Late Pleistocene and Holocene environments. In California Prehistory: Colonization, Culture, and Complexity (ed. T.L. Jones and K.A. Klar), pp. 11–34. Altamira Press, New York, USA. Williams, G.W. (2000). Introduction to aboriginal fire use in North America. Fire Management Today, 60, 8–12. Williams, M. (1989). Americans and Their Forests: A Historical Geography. Cambridge University Press, Cambridge, UK. Wright, H.A. & Bailey, A.W. (1980). Fire ecology and prescribed burning in the Great Plains: a research review. General Technical Report INT-77. USDA Forest Service, Ogden, UT, USA. Young, G.A. & Hoffman, M.P. (eds.). (1993). The Expedition of Hernando de Soto West of the Mississippi, 1541–1543. University of Arkansas Press, Fayetteville, AR, USA.