My last post discussed how the role of people in shaping the swampy systems of the Everglades had been erased. That erasure paralleled how biophysical processes had in the past been ignored in thinking about urban systems. Because Baltimore is a coastal city, it occurred to me while I was writing that post, that there were insights about the role of swamps and wetlands in the history of our city that would be worth exploring.
|Prof. Grace Brush|
Who better to lead us on that exploration than Professor Grace S. Brush, one of America’s leading paleoecologists — a scientist who studies past environments and the ecological networks that existed within them, usually by using fossil pollen or larger preserved parts of plants or animals? Here is her essay, reminding us of Baltimore’s important swampy heritage, and the implications for the Chesapeake Bay that result from the reduction or obliteration of those many swampy features. S.T.A.P.
|Beaver landscape (Morgan 1867)|
Historical maps published in 1897 show springs at the mouths of many tributaries. Druid Hill Park in Baltimore City has structures built for drinking water for horses at sites where ground water surfaced. They are now dry. Upland trees such as black locust and species of oak are replacing wetland species like green ash and box elder on floodplains of many streams. This phenomenon, which we have described as a “hydrological drought” is being reported in various parts of Eastern and Midwestern USA. All through the watershed, a very large beaver population created many marshes behind the numerous dams they built on inland streams All of the evidence points to a wet environment characterized by many marshes, swamps and ponds.
|Baltimore, 1792, with agricultural clearing.|
|Baltimore 1801, showing extensive, wet lowlands.|