Field Work 2018

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Purpose of the work

In the fall of 2018, the Muhlenberg Field Archaeology class studied the Blue Mountain land that was used for charcoal and iron production. The class conducted surveys and a small excavation of a collier's hut. During the study, the class utilized several methods including examination of LiDAR maps, pedestrian survey, shovel test pits, and metal detecting. The purpose of this research was to introduce students to survey methods and orient them to the landscape. Another goal of the research was to investigate the three collier’s huts on the side of the mountain through excavation[1]. An in depth investigation of the Collier's huts provides us with a deeper understanding of the charcoal industry and its impact on the environment and forestry, and a better picture of the lives of the Colliers. Through the field work, four new collier’s huts were identified in the field and three more potential ones were noted.


The plan of field work was to utilize several different methods of examination including the use of LiDAR maps, pedestrian survey, shovel test pits, and metal detecting[2]. Once the collier huts were identified, the area planned to be excavated would be in the “back” of the hut[3]. Charcoal pits were first identified by LiDAR, a form of remote sensing that measures the height of the land surface and vegetation across an area using a plane containing a combination of GPS, sensors/lasers, and an IMU (inertial measurement unit)[4]. On LiDAR data, the charcoal pits appear as “eyes” or flattened ovals on sloped terrain due to the clearing and leveling of the site to make charcoal[5]. The charcoal pits are easy to locate because they are perfectly level and 10 to 15 meters apart[6]. By combining the Digital Elevation Model with the LiDAR data, a more complete hill shade and slope analysis was created that revealed charcoal pits in greater detail and identified more pits than the initial LiDAR data[7]. Iron Furnaces were located by utilizing a combination of historic and modern maps[8]. Both the Lehigh and East Penn Furnace were located[9].


On the first day of fieldwork, an area was identified which served as an ideal space to conduct a systematic survey. Unfortunately, this did not occur because upon arrival, the class discovered that the area had not been maintained resulting in impenetrable growth. Due to this, a trip was taken to other hearths in the surrounding area that were identified on the LiDAR, but had not yet been confirmed in person[10]. Investigating the anomalies in the land proved helpful because they resulted in locating multiple collier huts. As result to the visual confirmation, we gained the capability recognize the "LiDAR signatures" for collier huts which makes identifying future huts much easier[11].

On the second day (9/23/2018), the class headed for collier huts 6, 13 and 14 and associated charcoal hearths (1292). Dr. Carter had discovered collier’s hut #6 when confirming charcoal hearths in the surrounding area on 6/29/2018. However, on 9/19/2018, Kenney and Dr.Carter spent half a day on the mountain. The goal was to set up the high resolution GPS. While doing this, it was discovered that not only was there one single collier’s hut (#6), but a total of three (the other two are #13 and #14). To have three collier’s huts in such close proximity to each other is unusual. This is also unusual because all other collier’s huts have been located on the flat top of the mountain, not on the slope, like 6, 13 and 14[12].

The team later chose the hut location to excavate based on the example with the least vegetation. As they excavated, the team moved the displaced branches, plants, etc. uphill 15m to a location they believed did not contain any cultural remains[13]. After this they decided to excavate the “berm” area that would have been opposite the door opening. The team thought this might provide evidence of berm wall, post holes or trench. They used trowels, brushes, scoops, clippers for the roots and mattocks and excavated at 10cm levels. They used ⅛” and ¼” screens to sift the soil, but the soil was damp and had many small rocks so it was difficult to screen the soil. No artifacts were actually found, but the team does believe they identified several other possible collier hut sites. A total of 206 points was collected which allowed the team to put together a Digital Elevation Model (DEM). The team believes the collier huts were located in this area on a slope because there was originally a road nearby that was used to move charcoal down the mountain.


Although excavation was extremely slow and artifacts were not recovered, important results were achieved from the work. Four new collier’s huts were identified in the field (8, 9, 13, and 14) and three more potential (10, 11, 12). Of the later three, 12 was later visited by Carter and determined to not be a collier’s hut[14]. In addition to identifying multiple collier's huts, collier’s huts 6, 13 and 14 along with charcoal hearth 1292 and the nearby historic road/path were mapped[15]. From this a total of 206 points were collected and a digital elevation model (DEM) was constructed and this allows the contours of both the charcoal hearths and huts to be visible on the DEM[16]. The archaeological work completed in this project contributes an improved understanding of the distribution of charcoal hearths, colliers huts, and roads. This helps us better understand the place in which the industry thrived as well as how the colliers utilized the landscape[17].


  1. Carter 2019, 35
  2. Carter 2019, 31
  3. Carter 2019, 41
  4. Carter 2019, 31
  5. Carter 2019, 32
  6. Carter 2019, 32
  7. Carter 2019, 32
  8. Carter 2019, 33
  9. Carter 2019, 33-35
  10. Carter 2019, 36
  11. Carter 2019, 36
  12. Carter 2019, 37
  13. Carter 2019, 39
  14. Carter 2019, 43
  15. Carter 2019, 43
  16. Carter 2019, 43
  17. Carter 2019, 48-49


  • Carter, Benjamin. 2019. Charcoal Lands: A report on archaeological investigations in State Games Lands #217 Fall 2018. Allentown, PA: Muhlenberg College.