An Ode to Dirt

You have probably never really thought about dirt... but you should.  One thing all archaeologists have in common is a love of getting dirty.  We can’t resist sticking our hands in it, checking out the texture & sometimes even the smell. (Occasionally, the taste but those people really are weird.)

Dirt comes in all kinds of textures... the obvious ones like sand and clay but, have you ever heard of loam or peat? Most people have.  There are about seven kinds of dirt (& by dirt I mean soil): Clay, Silty, Loamy, Sandy, Peaty, Saline, and Chalky.  When you say it like that it doesn’t sound all that exciting but stick your hands in each of those & you will see vast differences.  Those of you in the Mid-West know all about dirt with Clay in it and everyone knows that Peat helps to give Scotch it’s weird (I mean good) taste.

Let’s talk about Sandy for a second since that is what we are currently surrounded by.  Here in our little area alone there are many kinds of sand.  There is the typical beach sand (since the ocean is about 50 feet from our front door) but there is also hard packed sand that has been wet & dry a thousand times and is like concrete.  We literally use pick-axes to get it out.  Not 20 feet away from that is a substance so soft it’s like walking on flour (but a brown color).  I mean come on that’s fascinating!  What makes it do that?  Why are there so many different types & how do they form?  [Those are rhetorical questions, I know we know but it’s fun to think about how we know--did you follow that?]

This is the flour-like stuff, it makes little puffs when you walk.

There is actually a book of dirt colors called the Munsell Soil Chart.  We are so obsessed with dirt we like to know EXACTLY what the color is.  For those of you in the print world it’s sort of like Pantone colors.  There is a corresponding number for each color, so in 20 years you can go back to your notes & be like “Oh yes, it was 10YR 6/3 at Al-Baleed, I remember it fondly.”

This page is weird, who has blue dirt? 

You can pull out the page in your handy Munsell chart and match the dirt.  I had Sue & Brian show you how this works.  

So what do you think?  What color is this dirt?  This isn't on the site, it's near the house.

Now those of you who are really archaeologists don’t have a cow looking at the pictures.  I know you don’t have to put the pages in the dirt, but I was trying to let the readers/viewers see how the color charts work.  (Don’t tell Krista I used her book for this experiment.)  Typically, you hold some dirt on your trowel then hold it up to the book to match and everything stays clean.  (But where is the fun in that?)

Yes that is my trowel, yes it's rusty--I spend most of my time in the lab, give me a break.

I’ve also included some nerdy graphs for those of you who want to know how this dirt matching thing works.  (I stole these from the interwebs but I think they give you an idea of where the ranges of colors are and what the numbers mean.)

This is actually from a site in York, England but it gives you a good idea of the variety of soil colors.

Your assignment now is to go play in the dirt!  Actually look at it, stick your hands in it, give it a sniff... tasting is optional.

NOTE: I was just informed that, apparently, people who garden understand & obsess about soil almost as much as archaeologists--I wouldn’t know, I have a black thumb instead of green.