Ancient Anthropogenic Fire in Harlem
Back before Harlem became a borough of New York City, indeed before NYC ever existed, Manhattan Island was home to the Lenni Lenape, or Delaware people. The Delaware, as did other Algonquins, burned their habitat annually to induce open fields (cultivation by fire). These they planted with corn, squash, beans, and other domestic crops.
Or so has been hypothesized. Two researchers from UC Berkeley, William T. Bean and Eric W. Sanderson, devised a unique method of testing that hypothesis through the use of modern fire behavior models. Their report on their findings, Using a spatially explicit ecological model to test scenarios of fire use by Native Americans: An example from the Harlem Plains, New York, NY, has been added to the W.I.S.E. Colloquium: Forest and Fire Sciences [here].
Their findings in a nutshell:
Our model results indicate that by controlling fire frequency in the pre-settlement Harlem Plains, the Lenape people could control the structure of the landscape. Van der Donck’s claim that they cleared the land every 20 years does not appear to be supported by our model results. For the land to be a “plain” or “grassland” the landscape would have had to been burned at least once every 10 years and, depending on initial condition, would have yielded a mosaic of vegetation types. Burning every year overwhelms succession through disturbance and keeps the landscape in a grassland steady state.
Our results suggest that the hardwood forests of the northeast required significant maintenance in order to keep them clear and open—escaped fires and lightning strikes would not suffice to maintain a savanna or grassland. We believe this adds to the consensus that, while individual historical accounts may be suspect, the evidence continues to suggest that Native Americans were using fire to control their landscape, not only in the western and plains states, but also in the northeast.
Bean’s and Sanderson’s research constitute a novel use of modern fire behavior models, to “predict” the past rather than the future. The potential application of this technique is far-reaching.
We added this paper to our library of references at the suggestion of Dr. Frank Lake, Ph.D., our favorite Native American ecologist and a leader in combining modern science with traditional ecological knowledge and practices. Dr. Lake wrote:
To all,
In addition to my research on tribal community forestry/ethnobotany, PNW/Calif. tribal fire use and management, I have been a resource advisor on wildland fires (e.g. Ukonom and Siskiyou Complex 2008). During those wildfires, I worked with the Incident Command team GIS modelers using FSPro, FARSITE, and other models to predict how the wildfire would spread, identified resources at risks, set contingency boundaries, etc.
When working with them back in July 2008, I had the idea that those fire spread fuel/vegetation based models could likely be used and applied to reconstruct historical tribal ignition strategies for specific areas of the landscape (villages/camps, ridgeline trails, prairies/meadows, oak/pine dominated stands, etc.). That is, comparing the predicted fire spread (extent) of the models to what is known from fire history studies of the extent, frequency, and seasonality of fires, and the resultant associated vegetation (e.g. Pac. West. GLO surveys circa 1900, in Cal. Weislander circa 1930s).
I am not a modeler, and have very little experience with them other than the use with wildfires and reading articles by others who created and/or used those models. But I thought it would be a great tool, with various applications, to explore. …
Bean and Sanderson used FARSITE and historical data to test ignition seasonality and frequency for Harlem Plains, NY. I think their initial methodology is good, and has great potential if utilized by interdisciplinary scientific teams incorporating what is known about historical ecological (fire histories, vegetation, climate/weather, etc.) and cultural (tribal fire use, desired vegetation assemblages, archaeology, trails, camps/villages, etc.) processes or related attributes. …
I share my interest in Bean and Sanderson’s results with you because I think it addresses a (weakness or) criticism of my own and others’ work — who propose that tribal cultures burned as much as they did, and yet lack additional evidence besides a list of why, when, and where tribes used fire (compared to lightning ignitions too). I encourage you (historical/tribal documented reasons for fire use folks) to consider working with modelers to replicate these methods in other regions of North America. …
Thank you, Frank. Your suggestion is excellent and now has been passed on the anthropogenic fire cognoscenti.
The study of ancient landscapes (their conditions and developmental influences) are at the forefront of the New Paradigm. The old thinking in ecology was that natural forces (such as succession and mutualism) dictated the formation of vegetation types. The new thinking is that human beings have long been key players in landscape development pathways.
In case after case, landscape after landscape, from Harlem to the LA Basin to Amazonia, the evidence is accumulating — of significant and widespread human environmental manipulations dating back thousands of years.
Stewardship is an ancient practice. In some respects, that should be obvious. People are people and always have been. Now we have yet another scientific tool (fire behavior models) to probe the profundity of our ancient relationship with nature and our planet.
