Here we find the techniques in aikido which tend to bring uke under control, as with pins and joint locks such as oshi taoshi, waki gatame, or tenkai kote hinari.
With earth, one's ki is much, much more calm than with fire. In fact, earth is emotionless, being neither angry nor kind.
Though not as merciless as fire, it stems more from apathy than compassion.
Earth is steady, hardly moving. Ki moves in small increments, usually up and down—especially down.
Earth is patient, and will wait for uke to bring the attack, even baiting him. Like a python, earth allows uke to squirm all he likes, all the while crushing him gradually at the right moments with deceptive ease. Uke slowly crumples helplessly under earth, often digging his own hole from which he cannot escape.
Both earth and fire do not evade or escape; they own and command the line of movement, derailing uke.
Earth is comfortable with his tekui waza, his favorite techniques. They work, and he is content with his understanding of them. Consequently, he is reluctant to learn new things, or to explore other ways of doing what he always been doing. Many times, you will find brown belts and new black belts inhabiting the earth element.
Earth's attention is keen, even when one may think he isn't paying attention. He is very much in the moment. While fire tends to act on assumptions, earth is content with what is. That unflappable comfort can be very unnerving to opponents. He is intimidating to say the least.
I'm a student and instructor at Windsong Dojo in Oklahoma City, OK, where we study a non-competitive style of Tomiki Aikido, as well as Kodokan Judo, and Seitei Jodo. I've been studying budo for 19 years, and I hope to study many more. Welcome!