Charcoal Amendments: An Analysis of Soils from Historic Charcoaling Sites.

Charcoal Amendments: An Analysis of Soils from Historic Charcoaling Sites

Kevin Hesson

Charcoal amendments often yield different physical and chemical characteristics than soils without charcoal amendments. This research focused on enriched hearth soils which were the result of charcoaling for the iron industry in the 18th and 19th centuries. Samples were taken from charcoal hearth sites in Sterling  State Forest, N.Y. The study was conducted in order to determine whether soils sampled from charcoal hearths exhibit significantly different chemical and physical differences when compared with surrounding, non-hearth soils. Research was done to determine the differences between hearth and non hearth soils in terms of CEC, color, and pH. Two hearth and non-hearth soil profiles were sampled, at sites representing two types of glacial deposits: unsorted till and boulder fields. Hearth soils had higher CEC than non-hearth soils, with a profile-weighted average of 5.0 cmolc/kg for the hearth soils and 4.3 cmolc/kg for the non-hearth soil. The color for hearth soils were generally darker (lower L), bluer (lower ), with no measureable distinction in redness (a). These distinctions found in hearth soils were more pronounced in samples from the unsorted till site than the boulder field site. Soils from charcoal hearths also exhibited  higher pH values than non-hearth soils, even at depths extending below mixing during charcoal production and extraction from the hearths. The pH of non-hearth soils ranged from 3.8 (at the surface) to 4.8 (at 35 cm deep), while the pH of the charcoal hearth soils ranged from 4.1 (at the surface) to 5.3 (at 35 cm). These results demonstrate that charcoal amendments may have long term effects on the chemical and physical properties of soil.