I just returned to Kingston, Ontario from a whirlwind three weeks of travelling. I spent awhile in Colorado, mostly Colorado Springs and Denver, and then went on to present my research at the Canadian Society for Ecology and Evolution’s annual conference in St. John’s, Newfoundland. It was a mix of scorching heat and nipping cold, desert-like brush and lush green rolling hills, Rocky Mountains and coastal cliffs. It was amazing.
It wasn’t all just fun and games though. At the conference in St. John’s I presented one of the projects that I’ve been collecting data for 2 years for. I was interested in the role that body size played in predicting the abundance of seeds in the seed bank. So to answer this question, I went out and collected soil cores, which is a fancy way of saying I collected dirt.
I hadn’t put much thought into dirt before. I played with it as a kid, my brother used to eat it, it is brown, and plants grow in it. Even as a plant biologist I really hadn’t thought too much about it. After I started this experiment, I quickly realized that dirt was more than ‘just dirt’.
Early in April 2014 I collected my first set of soil cores. It was surprisingly laborious work with lots of bending and pulling to get 4 samples from each of 200 plots. Keep in mind that it was still teetering around 0 degrees C and doing things like opening Ziploc bags with mittens on is next to impossible. Timing here was critical because as soon as the first seeds germinated in that field, we would be too late. At each plot, 4 samples were taken and placed in the same plastic bag. They were then stored temporarily in a fridge at 4 degrees C until they could be processed.
Processing these soil cores was such a neat experience and it made me realize just how neat (and also cute and sometimes terrifying) dirt really is. The cores were all so different. Some had soft, loamy soil that fell apart and crumbled in between your fingers. Others were like taking a piece of freshly made fudge and squeezing it between your fingers. We would sort through the dirt and pull out rhizomes and pieces of roots, gently brush the dirt off and throw them away. We pulled out hundreds if not thousands of worms from the cores, as well as larva, dead insects and even sometimes bones of what appeared to be voles or other small mammals. On more than one occasion, the bag housed an army of ants, which then proceeded to attack everyone and everything at the table. Those bags were the ones I let the minions take care of…*gross*.
My favourite discovery was a small grey tree frog. I opened a Ziploc bag, took out a core, and as the dirt fell out onto the tray, a small tree frog hopped onto the table. As it came to it was just as confused as I was and attempted to hop away and right off the table (of course we released him somewhere a bit more suitable than the halls of the Biology building).
After the cores were all sorted we emptied each bag into a small plastic tray, and put it up in the Phytotron at Queen’s. We watered them and monitored them regularly, and what happened was pretty cool. Seeds from close to 60 species germinated and grew into tiny seedlings in those trays. Sometimes you would even see hundreds of individuals of different species coming up in one 4 x 6 inch tray.
This project, fieldwork, greenhouse work, and all, has remained one of my favourites I’ve done to date. Not for its simplicity, or low maintenance nature, but because it made me think about dirt, and dirt deserves a lot more credit than it gets because damn, it’s pretty neat.