Part of the Carbon in Global Boreal and Alpine Soils Under Climate Change-Driven Land Use fellowship sampling.

Alaska

Soils were collected from several farms near Delta Junction, Alaska, from mineral soils dominated by black spruce and converted to agriculture. Samples were taken for wheat, barley (no-till), barley rotated with cover crop (no-till), cover crop only (no-till), barley (conventional tillage), pasture (grazed), forest, and abandoned farmland.

The land was mostly flat with some slopes. All converted land used traditional Alaskan conversion (burning plant stumps and litter in the field), which leaves the soil with a substantial portion of biochar as well as extra-fertile veins of high carbon from the burning. Forest was dominated by black spruce and mosses/lichens with some birch; abandoned land had fireweed and small successional trees and shrubs. All farmland had forest hedges between fields. Most grain grown locally was barley, though the wheat field selected was conventionally tilled to match other sites. Soil texture appeared to be pure loess with some organic components. Samples were taken in one day and refrigerated. Farms were sampled with the help of Phil Kaspari (Alaska Extension) and local farmer and SWCD agent Bryce Wrigley.