# Soil names a like a puzzle ## Every soil is unique Soils are so much more than just a pile of brown stuff in which plants grow. Soils form in a vast diversity of colors, shapes, and forms. The observable properties of a soil depend on the context of it's formation. That is to say, the very nature of a soil depends on it's history. No single location on Earth has experience exactly the same history. Therefore, no two soils are exactly the same. That means that every time we dig a hole or come across a soil while out and about, we are greeting a unique soil entity. There's something just wonderful about that. ## Soils deserve to be named and recognized Knowing the name of something gives it respect and demonstrates that you value that thing. Calling soil "dirt" teaches us that soil is just the dirt under our shoes that doesn't deserve our attention and care. Calling soils by their names instead teaches us that soils are unique, and deserving of our curiosity. If we care enough to give something a name, we build an attachment to it that makes it more likely we will work to protect it. ## Scientists name soils based on their properties and formation In the same way that biologists group plants and animals together based on their physical features (known as morphology) or relatedness (known as phylogeny), soil scientists categorize soils based on similarities and differences in physical properties and formation processes. We have come up with many different ways to classify and group soils around the world. The World Reference Base system attempts to provide a global view of soil classification, while other systems of categorization are specific to a county or region. The origin of many of these classification systems comes from Indigenous descriptions of soil properties and uses. Here in the United States where I am based, we use the USDA Soil Taxonomy System. I'll be the first to say that the US soil taxonomy is not intuitive at first. It really is like learning a new language. Challenging as it might be to learn new words and phrases, there is a structure to the system. Unlike plants and animals, which are often named after people who described them, soils are named based on their features. Once you learn the structure of the categorization system, you can learn so much about a soil from just it's name. Practice enough and you'll be able to visualize what a soil looks and feels like within seconds of learning it's name. The US taxonomic system is organized in a hierarchical structure, starting with the most broadly defined groups and working towards incredibly specific, locally-constrained groups of soils. The broadest group, the soil order, categorizes soils based on the factors the control it's formation. These factors of soil formation include climate, parent material, topography, organisms, time, and humans. Here are a few examples: - Volcanic soils are unlike any other soils because they form from materials that have been ejected from a volcano during an eruption. So, volcanic soils (known as Andisols) are grouped in one soil order based on their parent material. - Soils forming in polar regions and at high elevations may experience climatic conditions cold enough to lead to the formation of permafrost. Permafrost is soil that remains frozen for two or more consecutive years. Of course this requires a specific climate, so permafrost soils (known as Gelisols) are grouped into one soil order based on climate. - Soil scientists in the US are in the process of creating a new category of soils in which humans are the most important soil forming factor. These human-dominated soils (Artesols) can occur in urban environments where soils have been moved around for construction purposes, or in areas with significant mining impacts. Once we have placed a soil into a category based on the big picture of how it came into being, then we can start getting a lot more specific. Scientists are always putting things into categories. We further subdivide soils into more specific categories called suborders, great groups, subgroups, and series. There are over 20,000 soil series in the US, so there's a lifetime to learning about soils just outside your doorstep. ![[coastal terrace MDO.jpg]] *An exposed soil forming in marine sediments along the coast of California.* ## Soil names are like a puzzle we can decode Each level of categorization has a specific letter code attached to it. For the volcanic soils (Andisols) I mentioned before, the code is "and". We build soil taxonomic names by attaching all the codes from each level of organization together into a long, sometimes unweildy, sometimes rather whimsical, scientific name. Here's the name of a volcanic soil found in Lassen Volcanic National Park in California: *Ashy-skeletal, amorphic Xeric Vitricryands* Here's an example of a permafrost soil in Alaska: *Glacic Histoturbel* Here's a soil found in Monterey county on the coast of California: *Sandy, mixed, thermic Entic Haploxerolls* The cool thing about this system is that you don't need to memorize all the names. You just need to learn some of the codes and know where to look up the key to codes you aren't yet familiar with (there's a book for this). Then, you can decode the name of just about any soil. Soil names are a puzzle that when solved, can quickly tell us a whole lot about the nature of that soil. ## Take home message Soils, just like plants, animals, rocks, and minerals, have scientific names. These names are mostly used to communicate soil properties between scientists, but there's also something whimsical about learning the names of the soils you interact with. You don't need to be a soil scientist to learn the names of soils and advocate for their conservation. Getting to know soils by name is a care practice and can be a fun exercise if you like decoding puzzles. If you live in the US, you can look up the soils around you using the Soil Web online tool. Thanks for making the time to care about soil. Please share what you learned with someone in your life. Talking about soils is a first and big step towards greater soil conservation. #### Postscript > This essay is part of [[One thing about soil - an educational series]] created by Dr. Yamina Pressler. The essay was originally shared on substack. *created April 12, 2023*