What did we learn about SOIL?

As a result of our Service Learning Project, we learned many key soil principles. One is that wetter is not always better regarding soil fertility. If a soil is completely saturated with water, there will be no oxygen available for root respiration. Also, roots can rot due to excess wetness. Many of us used to think that wet soils were the most fertile soils, alfisols and vertisols, the two soil orders represented at OCCUH, are less fertile than mollisols, which are found in drier climates.

We also learned that adding organic matter to improve fertility and aggregation only works up to a certain point. Cody discussed how adding too much organic matter makes the soil too acidic, as the soil at OCCUH is already pretty acidic to begin with due to aquic conditions.  Adding some organic matter is good, but Cody avoids adding too much so as not to create an overly acidic environment. Another way he counteracts soil acidity is by adding lime to the soil.

Additionally, soil high in clay and organic matter will be more protected from erosion than soil low in clay and organic matter. Organic matter residue on the surface of the soil creates a physical barrier between the soil and water or wind, reducing erosion. Clay and organic matter both function to create stable aggregates, the structure of which makes topsoil less prone to crusting and erosion. Clay can also dramatically increase the infiltration capacity of soil, reducing runoff. Overall as a group we learned that a lot of work goes into organic farming, because fertilizers cannot always be applied to manage the amount of nutrients within the soil. 

Hanging poblano peppers to dry in OCCUH's greenhouse