Illinois landowners could be eligible for $5,000 in free soil analyses and consultation with a University of Illinois Urbana-Champaign research team in exchange for participating in a historic project seeking to learn how soils have changed over 120 years. The project started when soil scientist Andrew Margenot stumbled upon a trove of ancient soil samples. Likely the oldest and largest soil archive in the world, the 8,000-sample collection was ripe for analysis.