The Fort Chambers / Poor Farm property contains fertile soils deposited from Boulder Creek.

There are four major soil types mapped within the agricultural lease areas: Calkins Sandy Loam, Nunn clay loam, Renohill silty clay loam and Loveland soils (Soil Survey Staff, 2022). Calkins sandy loam, which represents 39% of the lease area, is prime farmland if irrigated. Loveland soils and Nunn clay loam comprise 7% of the lease area and are also prime farmland if irrigated. Renohill silty clay loam, comprising 38% of the lease area, is designated as farmland of statewide importance (Natural Resources Conservation Service, 2022). Zoom and click to see the different soil types on the map.

These fertile soils were derived from the loamy alluvial deposits of the nearby Boulder and Four Mile Creeks. As such, these soils tend to have thicker profiles due to the deposition of eroded soil particles from adjacent areas. The intensive vegetable cropping is situated in the area dominated by the Calkins series. The Calkins soils are deep, but somewhat poorly drained. Drip irrigation, which delivers small amounts of water over time, prevents overirrigation. Soils within the Renohill type, while deep and well drained, are prone to erosion and are not suitable for intensive cropping (Moreland, 1975). These areas have been seeded to perennial grasses that are suitable for haying and grazing to minimize erosion.